Enhanced the SanitizeWhereClause function

.claude/readme

@@ -0,0 +1 @@
+We use claude for testing and document generation.

.env.example

@@ -0,0 +1,52 @@
+# ResolveSpec Environment Variables Example
+# Environment variables override config file settings
+# All variables are prefixed with RESOLVESPEC_
+# Nested config uses underscores (e.g., server.addr -> RESOLVESPEC_SERVER_ADDR)
+
+# Server Configuration
+RESOLVESPEC_SERVER_ADDR=:8080
+RESOLVESPEC_SERVER_SHUTDOWN_TIMEOUT=30s
+RESOLVESPEC_SERVER_DRAIN_TIMEOUT=25s
+RESOLVESPEC_SERVER_READ_TIMEOUT=10s
+RESOLVESPEC_SERVER_WRITE_TIMEOUT=10s
+RESOLVESPEC_SERVER_IDLE_TIMEOUT=120s
+
+# Tracing Configuration
+RESOLVESPEC_TRACING_ENABLED=false
+RESOLVESPEC_TRACING_SERVICE_NAME=resolvespec
+RESOLVESPEC_TRACING_SERVICE_VERSION=1.0.0
+RESOLVESPEC_TRACING_ENDPOINT=http://localhost:4318/v1/traces
+
+# Cache Configuration
+RESOLVESPEC_CACHE_PROVIDER=memory
+
+# Redis Cache (when provider=redis)
+RESOLVESPEC_CACHE_REDIS_HOST=localhost
+RESOLVESPEC_CACHE_REDIS_PORT=6379
+RESOLVESPEC_CACHE_REDIS_PASSWORD=
+RESOLVESPEC_CACHE_REDIS_DB=0
+
+# Memcache (when provider=memcache)
+# Note: For arrays, separate values with commas
+RESOLVESPEC_CACHE_MEMCACHE_SERVERS=localhost:11211
+RESOLVESPEC_CACHE_MEMCACHE_MAX_IDLE_CONNS=10
+RESOLVESPEC_CACHE_MEMCACHE_TIMEOUT=100ms
+
+# Logger Configuration
+RESOLVESPEC_LOGGER_DEV=false
+RESOLVESPEC_LOGGER_PATH=
+
+# Middleware Configuration
+RESOLVESPEC_MIDDLEWARE_RATE_LIMIT_RPS=100.0
+RESOLVESPEC_MIDDLEWARE_RATE_LIMIT_BURST=200
+RESOLVESPEC_MIDDLEWARE_MAX_REQUEST_SIZE=10485760
+
+# CORS Configuration
+# Note: For arrays in env vars, separate with commas
+RESOLVESPEC_CORS_ALLOWED_ORIGINS=*
+RESOLVESPEC_CORS_ALLOWED_METHODS=GET,POST,PUT,DELETE,OPTIONS
+RESOLVESPEC_CORS_ALLOWED_HEADERS=*
+RESOLVESPEC_CORS_MAX_AGE=3600
+
+# Database Configuration
+RESOLVESPEC_DATABASE_URL=host=localhost user=postgres password=postgres dbname=resolvespec_test port=5434 sslmode=disable

.github/workflows/maint.yml

@@ -1,4 +1,4 @@
-name: Tests
+name: Build , Vet Test, and Lint
 
 on:
   push:
@@ -9,7 +9,7 @@ on:
 
 jobs:
   test:
-    name: Run Tests
+    name: Run Vet Tests
     runs-on: ubuntu-latest
 
     strategy:
@@ -38,22 +38,6 @@ jobs:
       - name: Run go vet
         run: go vet ./...
 
-      - name: Run tests
-        run: go test -v -race -coverprofile=coverage.out -covermode=atomic ./...
-
-      - name: Display test coverage
-        run: go tool cover -func=coverage.out
-
-    # - name: Upload coverage to Codecov
-    #   uses: codecov/codecov-action@v4
-    #   with:
-    #     file: ./coverage.out
-    #     flags: unittests
-    #     name: codecov-umbrella
-    #   env:
-    #     CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
-    #   continue-on-error: true
-
   lint:
     name: Lint Code
     runs-on: ubuntu-latest

.github/workflows/tests.yml

@@ -0,0 +1,81 @@
+name: Tests
+on:
+  push:
+    branches: [main, develop]
+  pull_request:
+    branches: [main, develop]
+jobs:
+  unit-tests:
+    name: Unit Tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+      - name: Set up Go
+        uses: actions/setup-go@v6
+        with:
+          go-version: "1.24"
+      - name: Run unit tests
+        run: go test ./pkg/resolvespec ./pkg/restheadspec -v -cover
+      - name: Generate coverage report
+        run: |
+          go test ./pkg/resolvespec ./pkg/restheadspec -coverprofile=coverage.out
+          go tool cover -html=coverage.out -o coverage.html
+      - name: Upload coverage
+        uses: actions/upload-artifact@v5
+        with:
+          name: coverage-report
+          path: coverage.html
+  integration-tests:
+    name: Integration Tests
+    runs-on: ubuntu-latest
+    services:
+      postgres:
+        image: postgres:15-alpine
+        env:
+          POSTGRES_USER: postgres
+          POSTGRES_PASSWORD: postgres
+          POSTGRES_DB: postgres
+        options: >-
+          --health-cmd pg_isready
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
+        ports:
+          - 5432:5432
+    steps:
+      - uses: actions/checkout@v6
+      - name: Set up Go
+        uses: actions/setup-go@v6
+        with:
+          go-version: "1.24"
+      - name: Create test databases
+        env:
+          PGPASSWORD: postgres
+        run: |
+          psql -h localhost -U postgres -c "CREATE DATABASE resolvespec_test;"
+          psql -h localhost -U postgres -c "CREATE DATABASE restheadspec_test;"
+      - name: Run resolvespec integration tests
+        env:
+          TEST_DATABASE_URL: "host=localhost user=postgres password=postgres dbname=resolvespec_test port=5432 sslmode=disable"
+        run: go test -tags=integration ./pkg/resolvespec -v -coverprofile=coverage-resolvespec-integration.out
+      - name: Run restheadspec integration tests
+        env:
+          TEST_DATABASE_URL: "host=localhost user=postgres password=postgres dbname=restheadspec_test port=5432 sslmode=disable"
+        run: go test -tags=integration ./pkg/restheadspec -v -coverprofile=coverage-restheadspec-integration.out
+      - name: Generate integration coverage
+        env:
+          TEST_DATABASE_URL: "host=localhost user=postgres password=postgres dbname=resolvespec_test port=5432 sslmode=disable"
+        run: |
+          go tool cover -html=coverage-resolvespec-integration.out -o coverage-resolvespec-integration.html
+          go tool cover -html=coverage-restheadspec-integration.out -o coverage-restheadspec-integration.html
+      - name: Upload resolvespec integration coverage
+        uses: actions/upload-artifact@v5
+        with:
+          name: resolvespec-integration-coverage-report
+          path: coverage-resolvespec-integration.html
+
+      - name: Upload restheadspec integration coverage
+        uses: actions/upload-artifact@v5
+        with:
+          name: integration-coverage-restheadspec-report
+          path: coverage-restheadspec-integration

.golangci.json

@@ -86,7 +86,6 @@
           "emptyFallthrough",
           "equalFold",
           "flagName",
-          "ifElseChain",
           "indexAlloc",
           "initClause",
           "methodExprCall",
@@ -106,6 +105,9 @@
           "unnecessaryBlock",
           "weakCond",
           "yodaStyleExpr"
+        ],
+        "disabled-checks": [
+          "ifElseChain"
         ]
       },
       "revive": {

.vscode/settings.json

@@ -0,0 +1,56 @@
+{
+	"go.testFlags": [
+		"-v"
+	],
+	"go.testTimeout": "300s",
+	"go.coverOnSave": false,
+	"go.coverOnSingleTest": true,
+	"go.coverageDecorator": {
+		"type": "gutter"
+	},
+	"go.testEnvVars": {
+		"TEST_DATABASE_URL": "host=localhost user=postgres password=postgres dbname=resolvespec_test port=5432 sslmode=disable"
+	},
+	"go.toolsEnvVars": {
+		"CGO_ENABLED": "0"
+	},
+	"go.buildTags": "",
+	"go.testTags": "",
+	"files.exclude": {
+		"**/.git": true,
+		"**/.DS_Store": true,
+		"**/coverage.out": true,
+		"**/coverage.html": true,
+		"**/coverage-integration.out": true,
+		"**/coverage-integration.html": true
+	},
+	"files.watcherExclude": {
+		"**/.git/objects/**": true,
+		"**/.git/subtree-cache/**": true,
+		"**/node_modules/*/**": true,
+		"**/.hg/store/**": true,
+		"**/vendor/**": true
+	},
+	"editor.formatOnSave": true,
+	"editor.codeActionsOnSave": {
+		"source.organizeImports": "explicit"
+	},
+	"[go]": {
+		"editor.defaultFormatter": "golang.go",
+		"editor.formatOnSave": true,
+		"editor.insertSpaces": false,
+		"editor.tabSize": 4
+	},
+	"gopls": {
+		"ui.completion.usePlaceholders": true,
+		"ui.semanticTokens": true,
+		"ui.codelenses": {
+			"generate": true,
+			"regenerate_cgo": true,
+			"test": true,
+			"tidy": true,
+			"upgrade_dependency": true,
+			"vendor": true
+		}
+	}
+}

.vscode/tasks.json

@@ -6,10 +6,10 @@
 			"label": "go: build workspace",
 			"command": "build",
 			"options": {
-				"env": {				
+				"env": {
 					"CGO_ENABLED": "0"
 				},
-				"cwd": "${workspaceFolder}/bin",
+				"cwd": "${workspaceFolder}/bin"
 			},
 			"args": [
 				"../..."
@@ -17,12 +17,179 @@
 			"problemMatcher": [
 				"$go"
 			],
-			"group": "build",
-			
+			"group": "build"
+		},
+		{
+			"type": "shell",
+			"label": "test: unit tests (all)",
+			"command": "go test ./pkg/resolvespec ./pkg/restheadspec -v -cover",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [
+				"$go"
+			],
+			"group": {
+				"kind": "test",
+				"isDefault": true
+			},
+			"presentation": {
+				"reveal": "always",
+				"panel": "shared",
+				"focus": true
+			}
+		},
+		{
+			"type": "shell",
+			"label": "test: unit tests (resolvespec)",
+			"command": "go test ./pkg/resolvespec -v -cover",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [
+				"$go"
+			],
+			"group": "test",
+			"presentation": {
+				"reveal": "always",
+				"panel": "shared"
+			}
+		},
+		{
+			"type": "shell",
+			"label": "test: unit tests (restheadspec)",
+			"command": "go test ./pkg/restheadspec -v -cover",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [
+				"$go"
+			],
+			"group": "test",
+			"presentation": {
+				"reveal": "always",
+				"panel": "shared"
+			}
+		},
+		{
+			"type": "shell",
+			"label": "test: integration tests (automated)",
+			"command": "./scripts/run-integration-tests.sh",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [
+				"$go"
+			],
+			"group": "test",
+			"presentation": {
+				"reveal": "always",
+				"panel": "dedicated",
+				"focus": true
+			}
+		},
+		{
+			"type": "shell",
+			"label": "test: integration tests (resolvespec only)",
+			"command": "./scripts/run-integration-tests.sh resolvespec",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [
+				"$go"
+			],
+			"group": "test",
+			"presentation": {
+				"reveal": "always",
+				"panel": "dedicated"
+			}
+		},
+		{
+			"type": "shell",
+			"label": "test: integration tests (restheadspec only)",
+			"command": "./scripts/run-integration-tests.sh restheadspec",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [
+				"$go"
+			],
+			"group": "test",
+			"presentation": {
+				"reveal": "always",
+				"panel": "dedicated"
+			}
+		},
+		{
+			"type": "shell",
+			"label": "test: coverage report",
+			"command": "make coverage",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [],
+			"group": "test",
+			"presentation": {
+				"reveal": "always",
+				"panel": "shared"
+			}
+		},
+		{
+			"type": "shell",
+			"label": "test: integration coverage report",
+			"command": "make coverage-integration",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [],
+			"group": "test",
+			"presentation": {
+				"reveal": "always",
+				"panel": "shared"
+			}
+		},
+		{
+			"type": "shell",
+			"label": "docker: start postgres",
+			"command": "make docker-up",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [],
+			"presentation": {
+				"reveal": "always",
+				"panel": "shared"
+			}
+		},
+		{
+			"type": "shell",
+			"label": "docker: stop postgres",
+			"command": "make docker-down",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [],
+			"presentation": {
+				"reveal": "always",
+				"panel": "shared"
+			}
+		},
+		{
+			"type": "shell",
+			"label": "docker: clean postgres data",
+			"command": "make clean",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"problemMatcher": [],
+			"presentation": {
+				"reveal": "always",
+				"panel": "shared"
+			}
 		},
 		{
 			"type": "go",
-			"label": "go: test workspace",
+			"label": "go: test workspace (with race)",
 			"command": "test",
 			"options": {
 				"cwd": "${workspaceFolder}"
@@ -37,13 +204,10 @@
 			"problemMatcher": [
 				"$go"
 			],
-			"group": {
-				"kind": "test",
-				"isDefault": true
-			},
+			"group": "test",
 			"presentation": {
 				"reveal": "always",
-				"panel": "new"
+				"panel": "shared"
 			}
 		},
 		{
@@ -70,17 +234,45 @@
 		},
 		{
 			"type": "shell",
-			"label": "go: full test suite",
+			"label": "test: all tests (unit + integration)",
+			"command": "make test",
+			"options": {
+				"cwd": "${workspaceFolder}"
+			},
+			"dependsOn": [
+				"docker: start postgres"
+			],
+			"problemMatcher": [
+				"$go"
+			],
+			"group": "test",
+			"presentation": {
+				"reveal": "always",
+				"panel": "dedicated",
+				"focus": true
+			}
+		},
+		{
+			"type": "shell",
+			"label": "test: full suite with checks",
 			"dependsOrder": "sequence",
 			"dependsOn": [
 				"go: vet workspace",
-				"go: test workspace"
+				"test: unit tests (all)",
+				"test: integration tests (automated)"
 			],
 			"problemMatcher": [],
-			"group": {
-				"kind": "test",
-				"isDefault": false
+			"group": "test",
+			"presentation": {
+				"reveal": "always",
+				"panel": "dedicated"
 			}
+		},
+		{
+			"type": "shell",
+			"label": "Make Release",
+			"problemMatcher": [],
+			"command": "sh ${workspaceFolder}/make_release.sh"
 		}
 	]
-}
+}

MIGRATION_GUIDE.md

@@ -1,173 +0,0 @@
-# Migration Guide: Database and Router Abstraction
-
-This guide explains how to migrate from the direct GORM/Router dependencies to the new abstracted interfaces.
-
-## Overview of Changes
-
-### What was changed:
-1. **Database Operations**: GORM-specific code is now abstracted behind `Database` interface
-2. **Router Integration**: HTTP router dependencies are abstracted behind `Router` interface  
-3. **Model Registry**: Models are now managed through a `ModelRegistry` interface
-4. **Backward Compatibility**: Existing code continues to work with `NewAPIHandler()`
-
-### Benefits:
-- **Database Flexibility**: Switch between GORM, Bun, or other ORMs without code changes
-- **Router Flexibility**: Use Gorilla Mux, Gin, Echo, or other routers
-- **Better Testing**: Easy to mock database and router interactions
-- **Cleaner Separation**: Business logic separated from ORM/router specifics
-
-## Migration Path
-
-### Option 1: No Changes Required (Backward Compatible)
-Your existing code continues to work without any changes:
-
-```go
-// This still works exactly as before
-handler := resolvespec.NewAPIHandler(db)
-```
-
-### Option 2: Gradual Migration to New API
-
-#### Step 1: Use New Handler Constructor
-```go
-// Old way
-handler := resolvespec.NewAPIHandler(gormDB)
-
-// New way  
-handler := resolvespec.NewHandlerWithGORM(gormDB)
-```
-
-#### Step 2: Use Interface-based Approach
-```go
-// Create database adapter
-dbAdapter := resolvespec.NewGormAdapter(gormDB)
-
-// Create model registry
-registry := resolvespec.NewModelRegistry()
-
-// Register your models
-registry.RegisterModel("public.users", &User{})
-registry.RegisterModel("public.orders", &Order{})
-
-// Create handler
-handler := resolvespec.NewHandler(dbAdapter, registry)
-```
-
-## Switching Database Backends
-
-### From GORM to Bun
-```go
-// Add bun dependency first:
-// go get github.com/uptrace/bun
-
-// Old GORM setup
-gormDB, _ := gorm.Open(sqlite.Open("test.db"), &gorm.Config{})
-gormAdapter := resolvespec.NewGormAdapter(gormDB)
-
-// New Bun setup  
-sqlDB, _ := sql.Open("sqlite3", "test.db")
-bunDB := bun.NewDB(sqlDB, sqlitedialect.New())
-bunAdapter := resolvespec.NewBunAdapter(bunDB)
-
-// Handler creation is identical
-handler := resolvespec.NewHandler(bunAdapter, registry)
-```
-
-## Router Flexibility
-
-### Current Gorilla Mux (Default)
-```go
-router := mux.NewRouter()
-resolvespec.SetupRoutes(router, handler)
-```
-
-### BunRouter (Built-in Support)
-```go
-// Simple setup
-router := bunrouter.New()
-resolvespec.SetupBunRouterWithResolveSpec(router, handler)
-
-// Or using adapter
-routerAdapter := resolvespec.NewStandardBunRouterAdapter()
-// Use routerAdapter.GetBunRouter() for the underlying router
-```
-
-### Using Router Adapters (Advanced)
-```go
-// For when you want router abstraction
-routerAdapter := resolvespec.NewStandardRouter()
-routerAdapter.RegisterRoute("/{schema}/{entity}", handlerFunc)
-```
-
-## Model Registration
-
-### Old Way (Still Works)
-```go
-// Models registered through existing models package
-handler.RegisterModel("public", "users", &User{})
-```
-
-### New Way (Recommended)
-```go
-registry := resolvespec.NewModelRegistry()
-registry.RegisterModel("public.users", &User{})
-registry.RegisterModel("public.orders", &Order{})
-
-handler := resolvespec.NewHandler(dbAdapter, registry)
-```
-
-## Interface Definitions
-
-### Database Interface
-```go
-type Database interface {
-    NewSelect() SelectQuery
-    NewInsert() InsertQuery  
-    NewUpdate() UpdateQuery
-    NewDelete() DeleteQuery
-    // ... transaction methods
-}
-```
-
-### Available Adapters
-- `GormAdapter` - For GORM (ready to use)
-- `BunAdapter` - For Bun (add dependency: `go get github.com/uptrace/bun`)
-- Easy to create custom adapters for other ORMs
-
-## Testing Benefits
-
-### Before (Tightly Coupled)
-```go
-// Hard to test - requires real GORM setup
-func TestHandler(t *testing.T) {
-    db := setupRealGormDB()
-    handler := resolvespec.NewAPIHandler(db)
-    // ... test logic
-}
-```
-
-### After (Mockable)
-```go
-// Easy to test - mock the interfaces
-func TestHandler(t *testing.T) {
-    mockDB := &MockDatabase{}
-    mockRegistry := &MockModelRegistry{}
-    handler := resolvespec.NewHandler(mockDB, mockRegistry)
-    // ... test logic with mocks
-}
-```
-
-## Breaking Changes
-- **None for existing code** - Full backward compatibility maintained
-- New interfaces are additive, not replacing existing APIs
-
-## Recommended Migration Timeline
-1. **Phase 1**: Use existing code (no changes needed)
-2. **Phase 2**: Gradually adopt new constructors (`NewHandlerWithGORM`)
-3. **Phase 3**: Move to interface-based approach when needed
-4. **Phase 4**: Switch database backends if desired
-
-## Getting Help
-- Check example functions in `resolvespec.go`
-- Review interface definitions in `database.go`
-- Examine adapter implementations for patterns

Makefile

@@ -0,0 +1,66 @@
+.PHONY: test test-unit test-integration docker-up docker-down clean
+
+# Run all unit tests
+test-unit:
+	@echo "Running unit tests..."
+	@go test ./pkg/resolvespec ./pkg/restheadspec -v -cover
+
+# Run all integration tests (requires PostgreSQL)
+test-integration:
+	@echo "Running integration tests..."
+	@go test -tags=integration ./pkg/resolvespec ./pkg/restheadspec -v
+
+# Run all tests (unit + integration)
+test: test-unit test-integration
+
+# Start PostgreSQL for integration tests
+docker-up:
+	@echo "Starting PostgreSQL container..."
+	@docker-compose up -d postgres-test
+	@echo "Waiting for PostgreSQL to be ready..."
+	@sleep 5
+	@echo "PostgreSQL is ready!"
+
+# Stop PostgreSQL container
+docker-down:
+	@echo "Stopping PostgreSQL container..."
+	@docker-compose down
+
+# Clean up Docker volumes and test data
+clean:
+	@echo "Cleaning up..."
+	@docker-compose down -v
+	@echo "Cleanup complete!"
+
+# Run integration tests with Docker (full workflow)
+test-integration-docker: docker-up
+	@echo "Running integration tests with Docker..."
+	@go test -tags=integration ./pkg/resolvespec ./pkg/restheadspec -v
+	@$(MAKE) docker-down
+
+# Check test coverage
+coverage:
+	@echo "Generating coverage report..."
+	@go test ./pkg/resolvespec ./pkg/restheadspec -coverprofile=coverage.out
+	@go tool cover -html=coverage.out -o coverage.html
+	@echo "Coverage report generated: coverage.html"
+
+# Run integration tests coverage
+coverage-integration:
+	@echo "Generating integration test coverage report..."
+	@go test -tags=integration ./pkg/resolvespec ./pkg/restheadspec -coverprofile=coverage-integration.out
+	@go tool cover -html=coverage-integration.out -o coverage-integration.html
+	@echo "Integration coverage report generated: coverage-integration.html"
+
+help:
+	@echo "Available targets:"
+	@echo "  test-unit              - Run unit tests"
+	@echo "  test-integration       - Run integration tests (requires PostgreSQL)"
+	@echo "  test                   - Run all tests"
+	@echo "  docker-up              - Start PostgreSQL container"
+	@echo "  docker-down            - Stop PostgreSQL container"
+	@echo "  test-integration-docker - Run integration tests with Docker (automated)"
+	@echo "  clean                  - Clean up Docker volumes"
+	@echo "  coverage               - Generate unit test coverage report"
+	@echo "  coverage-integration   - Generate integration test coverage report"
+	@echo "  help                   - Show this help message"

README.md

@@ -1,73 +1,83 @@
 # 📜 ResolveSpec 📜
 
-![Tests](https://github.com/bitechdev/ResolveSpec/workflows/Tests/badge.svg)
+![1.00](https://github.com/bitechdev/ResolveSpec/workflows/Tests/badge.svg)
 
 ResolveSpec is a flexible and powerful REST API specification and implementation that provides GraphQL-like capabilities while maintaining REST simplicity. It offers **two complementary approaches**:
 
 1. **ResolveSpec** - Body-based API with JSON request options
 2. **RestHeadSpec** - Header-based API where query options are passed via HTTP headers
+3. **FuncSpec** - Header-based API to map and call API's to sql functions.
 
 Both share the same core architecture and provide dynamic data querying, relationship preloading, and complex filtering.
 
-**🆕 New in v2.0**: Database-agnostic architecture with support for GORM, Bun, and other ORMs. Router-flexible design works with Gorilla Mux, Gin, Echo, and more.
+Documentation Generated by LLMs
 
-**🆕 New in v2.1**: RestHeadSpec (HeaderSpec) - Header-based REST API with lifecycle hooks, cursor pagination, and advanced filtering.
-
-![slogan](./generated_slogan.webp)
+![1.00](./generated_slogan.webp)
 
 ## Table of Contents
 
-- [Features](#features)
-- [Installation](#installation)
-- [Quick Start](#quick-start)
-  - [ResolveSpec (Body-Based API)](#resolvespec-body-based-api)
-  - [RestHeadSpec (Header-Based API)](#restheadspec-header-based-api)
-  - [Existing Code (Backward Compatible)](#option-1-existing-code-backward-compatible)
-  - [New Database-Agnostic API](#option-2-new-database-agnostic-api)
-  - [Router Integration](#router-integration)
-- [Migration from v1.x](#migration-from-v1x)
-- [Architecture](#architecture)
-- [API Structure](#api-structure)
-- [RestHeadSpec: Header-Based API](#restheadspec-header-based-api-1)
-  - [Lifecycle Hooks](#lifecycle-hooks)
-  - [Cursor Pagination](#cursor-pagination)
-  - [Response Formats](#response-formats)
-  - [Single Record as Object](#single-record-as-object-default-behavior)
-- [Example Usage](#example-usage)
-  - [Recursive CRUD Operations](#recursive-crud-operations-)
-- [Testing](#testing)
-- [What's New](#whats-new)
+* [Features](#features)
+* [Installation](#installation)
+* [Quick Start](#quick-start)
+  * [ResolveSpec (Body-Based API)](#resolvespec-body-based-api)
+  * [RestHeadSpec (Header-Based API)](#restheadspec-header-based-api)
+  * [Existing Code (Backward Compatible)](#option-1-existing-code-backward-compatible)
+  * [New Database-Agnostic API](#option-2-new-database-agnostic-api)
+  * [Router Integration](#router-integration)
+* [Migration from v1.x](#migration-from-v1x)
+* [Architecture](#architecture)
+* [API Structure](#api-structure)
+* [RestHeadSpec: Header-Based API](#restheadspec-header-based-api-1)
+  * [Lifecycle Hooks](#lifecycle-hooks)
+  * [Cursor Pagination](#cursor-pagination)
+  * [Response Formats](#response-formats)
+  * [Single Record as Object](#single-record-as-object-default-behavior)
+* [Example Usage](#example-usage)
+  * [Recursive CRUD Operations](#recursive-crud-operations-)
+* [Testing](#testing)
+* [What's New](#whats-new)
 
 ## Features
 
 ### Core Features
-- **Dynamic Data Querying**: Select specific columns and relationships to return
-- **Relationship Preloading**: Load related entities with custom column selection and filters
-- **Complex Filtering**: Apply multiple filters with various operators
-- **Sorting**: Multi-column sort support
-- **Pagination**: Built-in limit/offset and cursor-based pagination
-- **Computed Columns**: Define virtual columns for complex calculations
-- **Custom Operators**: Add custom SQL conditions when needed
-- **🆕 Recursive CRUD Handler**: Automatically handle nested object graphs with foreign key resolution and per-record operation control via `_request` field
+
+* **Dynamic Data Querying**: Select specific columns and relationships to return
+* **Relationship Preloading**: Load related entities with custom column selection and filters
+* **Complex Filtering**: Apply multiple filters with various operators
+* **Sorting**: Multi-column sort support
+* **Pagination**: Built-in limit/offset and cursor-based pagination (both ResolveSpec and RestHeadSpec)
+* **Computed Columns**: Define virtual columns for complex calculations
+* **Custom Operators**: Add custom SQL conditions when needed
+* **🆕 Recursive CRUD Handler**: Automatically handle nested object graphs with foreign key resolution and per-record operation control via `_request` field
 
 ### Architecture (v2.0+)
-- **🆕 Database Agnostic**: Works with GORM, Bun, or any database layer through adapters
-- **🆕 Router Flexible**: Integrates with Gorilla Mux, Gin, Echo, or custom routers
-- **🆕 Backward Compatible**: Existing code works without changes
-- **🆕 Better Testing**: Mockable interfaces for easy unit testing
+
+* **🆕 Database Agnostic**: Works with GORM, Bun, or any database layer through adapters
+* **🆕 Router Flexible**: Integrates with Gorilla Mux, Gin, Echo, or custom routers
+* **🆕 Backward Compatible**: Existing code works without changes
+* **🆕 Better Testing**: Mockable interfaces for easy unit testing
 
 ### RestHeadSpec (v2.1+)
-- **🆕 Header-Based API**: All query options passed via HTTP headers instead of request body
-- **🆕 Lifecycle Hooks**: Before/after hooks for create, read, update, and delete operations
-- **🆕 Cursor Pagination**: Efficient cursor-based pagination with complex sort support
-- **🆕 Multiple Response Formats**: Simple, detailed, and Syncfusion-compatible formats
-- **🆕 Single Record as Object**: Automatically normalize single-element arrays to objects (enabled by default)
-- **🆕 Advanced Filtering**: Field filters, search operators, AND/OR logic, and custom SQL
-- **🆕 Base64 Encoding**: Support for base64-encoded header values
+
+* **🆕 Header-Based API**: All query options passed via HTTP headers instead of request body
+* **🆕 Lifecycle Hooks**: Before/after hooks for create, read, update, and delete operations
+* **🆕 Cursor Pagination**: Efficient cursor-based pagination with complex sort support
+* **🆕 Multiple Response Formats**: Simple, detailed, and Syncfusion-compatible formats
+* **🆕 Single Record as Object**: Automatically normalize single-element arrays to objects (enabled by default)
+* **🆕 Advanced Filtering**: Field filters, search operators, AND/OR logic, and custom SQL
+* **🆕 Base64 Encoding**: Support for base64-encoded header values
+
+### Routing & CORS (v3.0+)
+
+* **🆕 Explicit Route Registration**: Routes created per registered model instead of dynamic lookups
+* **🆕 OPTIONS Method Support**: Full OPTIONS method support returning model metadata
+* **🆕 CORS Headers**: Comprehensive CORS support with all HeadSpec headers allowed
+* **🆕 Better Route Control**: Customize routes per model with more flexibility
 
 ## API Structure
 
 ### URL Patterns
+
 ```
 /[schema]/[table_or_entity]/[id]
 /[schema]/[table_or_entity]
@@ -77,7 +87,7 @@ Both share the same core architecture and provide dynamic data querying, relatio
 
 ### Request Format
 
-```json
+```JSON
 {
   "operation": "read|create|update|delete",
   "data": {
@@ -102,7 +112,7 @@ RestHeadSpec provides an alternative REST API approach where all query options a
 
 ### Quick Example
 
-```http
+```HTTP
 GET /public/users HTTP/1.1
 Host: api.example.com
 X-Select-Fields: id,name,email,department_id
@@ -116,20 +126,22 @@ X-DetailApi: true
 
 ### Setup with GORM
 
-```go
+```Go
 import "github.com/bitechdev/ResolveSpec/pkg/restheadspec"
 import "github.com/gorilla/mux"
 
 // Create handler
 handler := restheadspec.NewHandlerWithGORM(db)
 
-// Register models using schema.table format
+// IMPORTANT: Register models BEFORE setting up routes
+// Routes are created explicitly for each registered model
 handler.Registry.RegisterModel("public.users", &User{})
 handler.Registry.RegisterModel("public.posts", &Post{})
 
-// Setup routes
+// Setup routes (creates explicit routes for each registered model)
+// This replaces the old dynamic route lookup approach
 router := mux.NewRouter()
-restheadspec.SetupMuxRoutes(router, handler)
+restheadspec.SetupMuxRoutes(router, handler, nil)
 
 // Start server
 http.ListenAndServe(":8080", router)
@@ -137,7 +149,7 @@ http.ListenAndServe(":8080", router)
 
 ### Setup with Bun ORM
 
-```go
+```Go
 import "github.com/bitechdev/ResolveSpec/pkg/restheadspec"
 import "github.com/uptrace/bun"
 
@@ -154,29 +166,70 @@ restheadspec.SetupMuxRoutes(router, handler)
 
 ### Common Headers
 
-| Header | Description | Example |
-|--------|-------------|---------|
-| `X-Select-Fields` | Columns to include | `id,name,email` |
-| `X-Not-Select-Fields` | Columns to exclude | `password,internal_notes` |
-| `X-FieldFilter-{col}` | Exact match filter | `X-FieldFilter-Status: active` |
-| `X-SearchFilter-{col}` | Fuzzy search (ILIKE) | `X-SearchFilter-Name: john` |
-| `X-SearchOp-{op}-{col}` | Filter with operator | `X-SearchOp-Gte-Age: 18` |
-| `X-Preload` | Preload relations | `posts:id,title` |
-| `X-Sort` | Sort columns | `-created_at,+name` |
-| `X-Limit` | Limit results | `50` |
-| `X-Offset` | Offset for pagination | `100` |
-| `X-Clean-JSON` | Remove null/empty fields | `true` |
-| `X-Single-Record-As-Object` | Return single records as objects (default: `true`) | `false` |
+| Header                      | Description                                        | Example                        |
+| --------------------------- | -------------------------------------------------- | ------------------------------ |
+| `X-Select-Fields`           | Columns to include                                 | `id,name,email`                |
+| `X-Not-Select-Fields`       | Columns to exclude                                 | `password,internal_notes`      |
+| `X-FieldFilter-{col}`       | Exact match filter                                 | `X-FieldFilter-Status: active` |
+| `X-SearchFilter-{col}`      | Fuzzy search (ILIKE)                               | `X-SearchFilter-Name: john`    |
+| `X-SearchOp-{op}-{col}`     | Filter with operator                               | `X-SearchOp-Gte-Age: 18`       |
+| `X-Preload`                 | Preload relations                                  | `posts:id,title`               |
+| `X-Sort`                    | Sort columns                                       | `-created_at,+name`            |
+| `X-Limit`                   | Limit results                                      | `50`                           |
+| `X-Offset`                  | Offset for pagination                              | `100`                          |
+| `X-Clean-JSON`              | Remove null/empty fields                           | `true`                         |
+| `X-Single-Record-As-Object` | Return single records as objects (default: `true`) | `false`                        |
 
 **Available Operators**: `eq`, `neq`, `gt`, `gte`, `lt`, `lte`, `contains`, `startswith`, `endswith`, `between`, `betweeninclusive`, `in`, `empty`, `notempty`
 
 For complete header documentation, see [pkg/restheadspec/HEADERS.md](pkg/restheadspec/HEADERS.md).
 
+### CORS & OPTIONS Support
+
+ResolveSpec and RestHeadSpec include comprehensive CORS support for cross-origin requests:
+
+**OPTIONS Method**:
+
+```HTTP
+OPTIONS /public/users HTTP/1.1
+```
+
+Returns metadata with appropriate CORS headers:
+
+```HTTP
+Access-Control-Allow-Origin: *
+Access-Control-Allow-Methods: GET, POST, OPTIONS
+Access-Control-Allow-Headers: Content-Type, Authorization, X-Select-Fields, X-FieldFilter-*, ...
+Access-Control-Max-Age: 86400
+Access-Control-Allow-Credentials: true
+```
+
+**Key Features**:
+
+* OPTIONS returns model metadata (same as GET metadata endpoint)
+* All HTTP methods include CORS headers automatically
+* OPTIONS requests don't require authentication (CORS preflight)
+* Supports all HeadSpec custom headers (`X-Select-Fields`, `X-FieldFilter-*`, etc.)
+* 24-hour max age to reduce preflight requests
+
+**Configuration**:
+
+```Go
+import "github.com/bitechdev/ResolveSpec/pkg/common"
+
+// Get default CORS config
+corsConfig := common.DefaultCORSConfig()
+
+// Customize if needed
+corsConfig.AllowedOrigins = []string{"https://example.com"}
+corsConfig.AllowedMethods = []string{"GET", "POST", "PUT", "DELETE", "OPTIONS"}
+```
+
 ### Lifecycle Hooks
 
 RestHeadSpec supports lifecycle hooks for all CRUD operations:
 
-```go
+```Go
 import "github.com/bitechdev/ResolveSpec/pkg/restheadspec"
 
 // Create handler
@@ -221,27 +274,29 @@ handler.Hooks.Register(restheadspec.BeforeCreate, func(ctx *restheadspec.HookCon
 ```
 
 **Available Hook Types**:
-- `BeforeRead`, `AfterRead`
-- `BeforeCreate`, `AfterCreate`
-- `BeforeUpdate`, `AfterUpdate`
-- `BeforeDelete`, `AfterDelete`
+
+* `BeforeRead`, `AfterRead`
+* `BeforeCreate`, `AfterCreate`
+* `BeforeUpdate`, `AfterUpdate`
+* `BeforeDelete`, `AfterDelete`
 
 **HookContext** provides:
-- `Context`: Request context
-- `Handler`: Access to handler, database, and registry
-- `Schema`, `Entity`, `TableName`: Request info
-- `Model`: The registered model type
-- `Options`: Parsed request options (filters, sorting, etc.)
-- `ID`: Record ID (for single-record operations)
-- `Data`: Request data (for create/update)
-- `Result`: Operation result (for after hooks)
-- `Writer`: Response writer (allows hooks to modify response)
+
+* `Context`: Request context
+* `Handler`: Access to handler, database, and registry
+* `Schema`, `Entity`, `TableName`: Request info
+* `Model`: The registered model type
+* `Options`: Parsed request options (filters, sorting, etc.)
+* `ID`: Record ID (for single-record operations)
+* `Data`: Request data (for create/update)
+* `Result`: Operation result (for after hooks)
+* `Writer`: Response writer (allows hooks to modify response)
 
 ### Cursor Pagination
 
 RestHeadSpec supports efficient cursor-based pagination for large datasets:
 
-```http
+```HTTP
 GET /public/posts HTTP/1.1
 X-Sort: -created_at,+id
 X-Limit: 50
@@ -249,20 +304,22 @@ X-Cursor-Forward: <cursor_token>
 ```
 
 **How it works**:
+
 1. First request returns results + cursor token in response
 2. Subsequent requests use `X-Cursor-Forward` or `X-Cursor-Backward`
 3. Cursor maintains consistent ordering even with data changes
 4. Supports complex multi-column sorting
 
 **Benefits over offset pagination**:
-- Consistent results when data changes
-- Better performance for large offsets
-- Prevents "skipped" or duplicate records
-- Works with complex sort expressions
+
+* Consistent results when data changes
+* Better performance for large offsets
+* Prevents "skipped" or duplicate records
+* Works with complex sort expressions
 
 **Example with hooks**:
 
-```go
+```Go
 // Enable cursor pagination in a hook
 handler.Hooks.Register(restheadspec.BeforeRead, func(ctx *restheadspec.HookContext) error {
     // For large tables, enforce cursor pagination
@@ -278,7 +335,8 @@ handler.Hooks.Register(restheadspec.BeforeRead, func(ctx *restheadspec.HookConte
 RestHeadSpec supports multiple response formats:
 
 **1. Simple Format** (`X-SimpleApi: true`):
-```json
+
+```JSON
 [
   { "id": 1, "name": "John" },
   { "id": 2, "name": "Jane" }
@@ -286,7 +344,8 @@ RestHeadSpec supports multiple response formats:
 ```
 
 **2. Detail Format** (`X-DetailApi: true`, default):
-```json
+
+```JSON
 {
   "success": true,
   "data": [...],
@@ -300,7 +359,8 @@ RestHeadSpec supports multiple response formats:
 ```
 
 **3. Syncfusion Format** (`X-Syncfusion: true`):
-```json
+
+```JSON
 {
   "result": [...],
   "count": 100
@@ -312,10 +372,12 @@ RestHeadSpec supports multiple response formats:
 By default, RestHeadSpec automatically converts single-element arrays into objects for cleaner API responses. This provides a better developer experience when fetching individual records.
 
 **Default behavior (enabled)**:
-```http
+
+```HTTP
 GET /public/users/123
 ```
-```json
+
+```JSON
 {
   "success": true,
   "data": { "id": 123, "name": "John", "email": "john@example.com" }
@@ -323,7 +385,8 @@ GET /public/users/123
 ```
 
 Instead of:
-```json
+
+```JSON
 {
   "success": true,
   "data": [{ "id": 123, "name": "John", "email": "john@example.com" }]
@@ -331,11 +394,13 @@ Instead of:
 ```
 
 **To disable** (force arrays for consistency):
-```http
+
+```HTTP
 GET /public/users/123
 X-Single-Record-As-Object: false
 ```
-```json
+
+```JSON
 {
   "success": true,
   "data": [{ "id": 123, "name": "John", "email": "john@example.com" }]
@@ -343,23 +408,26 @@ X-Single-Record-As-Object: false
 ```
 
 **How it works**:
-- When a query returns exactly **one record**, it's returned as an object
-- When a query returns **multiple records**, they're returned as an array
-- Set `X-Single-Record-As-Object: false` to always receive arrays
-- Works with all response formats (simple, detail, syncfusion)
-- Applies to both read operations and create/update returning clauses
+
+* When a query returns exactly **one record**, it's returned as an object
+* When a query returns **multiple records**, they're returned as an array
+* Set `X-Single-Record-As-Object: false` to always receive arrays
+* Works with all response formats (simple, detail, syncfusion)
+* Applies to both read operations and create/update returning clauses
 
 **Benefits**:
-- Cleaner API responses for single-record queries
-- No need to unwrap single-element arrays on the client side
-- Better TypeScript/type inference support
-- Consistent with common REST API patterns
-- Backward compatible via header opt-out
+
+* Cleaner API responses for single-record queries
+* No need to unwrap single-element arrays on the client side
+* Better TypeScript/type inference support
+* Consistent with common REST API patterns
+* Backward compatible via header opt-out
 
 ## Example Usage
 
 ### Reading Data with Related Entities
-```json
+
+```JSON
 POST /core/users
 {
   "operation": "read",
@@ -397,13 +465,89 @@ POST /core/users
 }
 ```
 
+### Cursor Pagination (ResolveSpec)
+
+ResolveSpec now supports cursor-based pagination for efficient traversal of large datasets:
+
+```JSON
+POST /core/posts
+{
+  "operation": "read",
+  "options": {
+    "sort": [
+      {
+        "column": "created_at",
+        "direction": "desc"
+      },
+      {
+        "column": "id",
+        "direction": "asc"
+      }
+    ],
+    "limit": 50,
+    "cursor_forward": "12345"
+  }
+}
+```
+
+**How it works**:
+1. First request returns results + cursor token (last record's ID)
+2. Subsequent requests use `cursor_forward` or `cursor_backward` in options
+3. Cursor maintains consistent ordering even when data changes
+4. Supports complex multi-column sorting
+
+**Benefits over offset pagination**:
+- Consistent results when data changes between requests
+- Better performance for large offsets
+- Prevents "skipped" or duplicate records
+- Works with complex sort expressions
+
+**Example request sequence**:
+
+```JSON
+// First request - no cursor
+POST /core/posts
+{
+  "operation": "read",
+  "options": {
+    "sort": [{"column": "created_at", "direction": "desc"}],
+    "limit": 50
+  }
+}
+
+// Response includes data + last record ID
+// Use the last record's ID as cursor_forward for next page
+
+// Second request - with cursor
+POST /core/posts
+{
+  "operation": "read",
+  "options": {
+    "sort": [{"column": "created_at", "direction": "desc"}],
+    "limit": 50,
+    "cursor_forward": "12345"  // ID of last record from previous page
+  }
+}
+
+// For backward pagination
+POST /core/posts
+{
+  "operation": "read",
+  "options": {
+    "sort": [{"column": "created_at", "direction": "desc"}],
+    "limit": 50,
+    "cursor_backward": "12300"  // ID of first record from current page
+  }
+}
+```
+
 ### Recursive CRUD Operations (🆕)
 
 ResolveSpec now supports automatic handling of nested object graphs with intelligent foreign key resolution. This allows you to create, update, or delete entire object hierarchies in a single request.
 
 #### Creating Nested Objects
 
-```json
+```JSON
 POST /core/users
 {
   "operation": "create",
@@ -436,7 +580,7 @@ POST /core/users
 
 Control individual operations for each nested record using the special `_request` field:
 
-```json
+```JSON
 POST /core/users/123
 {
   "operation": "update",
@@ -462,11 +606,12 @@ POST /core/users/123
 }
 ```
 
-**Supported `_request` values**:
-- `insert` - Create a new related record
-- `update` - Update an existing related record
-- `delete` - Delete a related record
-- `upsert` - Create if doesn't exist, update if exists
+**Supported** **`_request`** **values**:
+
+* `insert` - Create a new related record
+* `update` - Update an existing related record
+* `delete` - Delete a related record
+* `upsert` - Create if doesn't exist, update if exists
 
 #### How It Works
 
@@ -478,14 +623,14 @@ POST /core/users/123
 
 #### Benefits
 
-- Reduce API round trips for complex object graphs
-- Maintain referential integrity automatically
-- Simplify client-side code
-- Atomic operations with automatic rollback on errors
+* Reduce API round trips for complex object graphs
+* Maintain referential integrity automatically
+* Simplify client-side code
+* Atomic operations with automatic rollback on errors
 
 ## Installation
 
-```bash
+```Shell
 go get github.com/bitechdev/ResolveSpec
 ```
 
@@ -495,7 +640,7 @@ go get github.com/bitechdev/ResolveSpec
 
 ResolveSpec uses JSON request bodies to specify query options:
 
-```go
+```Go
 import "github.com/bitechdev/ResolveSpec/pkg/resolvespec"
 
 // Create handler
@@ -522,7 +667,7 @@ resolvespec.SetupRoutes(router, handler)
 
 RestHeadSpec uses HTTP headers for query options instead of request body:
 
-```go
+```Go
 import "github.com/bitechdev/ResolveSpec/pkg/restheadspec"
 
 // Create handler with GORM
@@ -551,7 +696,7 @@ See [RestHeadSpec: Header-Based API](#restheadspec-header-based-api-1) for compl
 
 Your existing code continues to work without any changes:
 
-```go
+```Go
 import "github.com/bitechdev/ResolveSpec/pkg/resolvespec"
 
 // This still works exactly as before
@@ -569,7 +714,7 @@ ResolveSpec v2.0 introduces a new database and router abstraction layer while ma
 
 To update your imports:
 
-```bash
+```Shell
 # Update go.mod
 go mod edit -replace github.com/Warky-Devs/ResolveSpec=github.com/bitechdev/ResolveSpec@latest
 go mod tidy
@@ -581,7 +726,7 @@ go mod tidy
 
 Alternatively, use find and replace in your project:
 
-```bash
+```Shell
 find . -type f -name "*.go" -exec sed -i 's|github.com/Warky-Devs/ResolveSpec|github.com/bitechdev/ResolveSpec|g' {} +
 go mod tidy
 ```
@@ -596,7 +741,7 @@ go mod tidy
 
 ### Detailed Migration Guide
 
-For detailed migration instructions, examples, and best practices, see [MIGRATION_GUIDE.md](MIGRATION_GUIDE.md).
+For detailed migration instructions, examples, and best practices, see [MIGRATION\_GUIDE.md](MIGRATION_GUIDE.md).
 
 ## Architecture
 
@@ -638,22 +783,23 @@ Your Application Code
 
 ### Supported Database Layers
 
-- **GORM** (default, fully supported)
-- **Bun** (ready to use, included in dependencies)
-- **Custom ORMs** (implement the `Database` interface)
+* **GORM** (default, fully supported)
+* **Bun** (ready to use, included in dependencies)
+* **Custom ORMs** (implement the `Database` interface)
 
 ### Supported Routers
 
-- **Gorilla Mux** (built-in support with `SetupRoutes()`)
-- **BunRouter** (built-in support with `SetupBunRouterWithResolveSpec()`)
-- **Gin** (manual integration, see examples above)
-- **Echo** (manual integration, see examples above)  
-- **Custom Routers** (implement request/response adapters)
+* **Gorilla Mux** (built-in support with `SetupRoutes()`)
+* **BunRouter** (built-in support with `SetupBunRouterWithResolveSpec()`)
+* **Gin** (manual integration, see examples above)
+* **Echo** (manual integration, see examples above)
+* **Custom Routers** (implement request/response adapters)
 
 ### Option 2: New Database-Agnostic API
 
 #### With GORM (Recommended Migration Path)
-```go
+
+```Go
 import "github.com/bitechdev/ResolveSpec/pkg/resolvespec"
 
 // Create database adapter
@@ -669,7 +815,8 @@ handler := resolvespec.NewHandler(dbAdapter, registry)
 ```
 
 #### With Bun ORM
-```go
+
+```Go
 import "github.com/bitechdev/ResolveSpec/pkg/resolvespec"
 import "github.com/uptrace/bun"
 
@@ -684,22 +831,25 @@ handler := resolvespec.NewHandler(dbAdapter, registry)
 ### Router Integration
 
 #### Gorilla Mux (Built-in Support)
-```go
+
+```Go
 import "github.com/gorilla/mux"
 
-// Backward compatible way
-router := mux.NewRouter()  
-resolvespec.SetupRoutes(router, handler)
+// Register models first
+handler.Registry.RegisterModel("public.users", &User{})
+handler.Registry.RegisterModel("public.posts", &Post{})
 
-// Or manually:
-router.HandleFunc("/{schema}/{entity}", func(w http.ResponseWriter, r *http.Request) {
-    vars := mux.Vars(r)
-    handler.Handle(w, r, vars)
-}).Methods("POST")
+// Setup routes - creates explicit routes for each model
+router := mux.NewRouter()
+resolvespec.SetupMuxRoutes(router, handler, nil)
+
+// Routes created: /public/users, /public/posts, etc.
+// Each route includes GET, POST, and OPTIONS methods with CORS support
 ```
 
 #### Gin (Custom Integration)
-```go
+
+```Go
 import "github.com/gin-gonic/gin"
 
 func setupGin(handler *resolvespec.Handler) *gin.Engine {
@@ -722,7 +872,8 @@ func setupGin(handler *resolvespec.Handler) *gin.Engine {
 ```
 
 #### Echo (Custom Integration)
-```go
+
+```Go
 import "github.com/labstack/echo/v4"
 
 func setupEcho(handler *resolvespec.Handler) *echo.Echo {
@@ -745,7 +896,8 @@ func setupEcho(handler *resolvespec.Handler) *echo.Echo {
 ```
 
 #### BunRouter (Built-in Support)
-```go
+
+```Go
 import "github.com/uptrace/bunrouter"
 
 // Simple setup with built-in function
@@ -790,7 +942,8 @@ func setupFullUptrace(bunDB *bun.DB) *bunrouter.Router {
 ## Configuration
 
 ### Model Registration
-```go
+
+```Go
 type User struct {
     ID    uint   `json:"id" gorm:"primaryKey"`
     Name  string `json:"name"`
@@ -804,20 +957,24 @@ handler.RegisterModel("core", "users", &User{})
 ## Features in Detail
 
 ### Filtering
+
 Supported operators:
-- eq: Equal
-- neq: Not Equal
-- gt: Greater Than
-- gte: Greater Than or Equal
-- lt: Less Than
-- lte: Less Than or Equal
-- like: LIKE pattern matching
-- ilike: Case-insensitive LIKE
-- in: IN clause
+
+* eq: Equal
+* neq: Not Equal
+* gt: Greater Than
+* gte: Greater Than or Equal
+* lt: Less Than
+* lte: Less Than or Equal
+* like: LIKE pattern matching
+* ilike: Case-insensitive LIKE
+* in: IN clause
 
 ### Sorting
+
 Support for multiple sort criteria with direction:
-```json
+
+```JSON
 "sort": [
   {
     "column": "created_at",
@@ -831,8 +988,10 @@ Support for multiple sort criteria with direction:
 ```
 
 ### Computed Columns
+
 Define virtual columns using SQL expressions:
-```json
+
+```JSON
 "computedColumns": [
   {
     "name": "full_name",
@@ -845,7 +1004,7 @@ Define virtual columns using SQL expressions:
 
 ### With New Architecture (Mockable)
 
-```go
+```Go
 import "github.com/stretchr/testify/mock"
 
 // Create mock database
@@ -880,14 +1039,14 @@ ResolveSpec uses GitHub Actions for automated testing and quality checks. The CI
 
 The project includes automated workflows that:
 
-- **Test**: Run all tests with race detection and code coverage
-- **Lint**: Check code quality with golangci-lint
-- **Build**: Verify the project builds successfully
-- **Multi-version**: Test against multiple Go versions (1.23.x, 1.24.x)
+* **Test**: Run all tests with race detection and code coverage
+* **Lint**: Check code quality with golangci-lint
+* **Build**: Verify the project builds successfully
+* **Multi-version**: Test against multiple Go versions (1.23.x, 1.24.x)
 
 ### Running Tests Locally
 
-```bash
+```Shell
 # Run all tests
 go test -v ./...
 
@@ -905,13 +1064,13 @@ golangci-lint run
 
 The project includes comprehensive test coverage:
 
-- **Unit Tests**: Individual component testing
-- **Integration Tests**: End-to-end API testing
-- **CRUD Tests**: Standalone tests for both ResolveSpec and RestHeadSpec APIs
+* **Unit Tests**: Individual component testing
+* **Integration Tests**: End-to-end API testing
+* **CRUD Tests**: Standalone tests for both ResolveSpec and RestHeadSpec APIs
 
 To run only the CRUD standalone tests:
 
-```bash
+```Shell
 go test -v ./tests -run TestCRUDStandalone
 ```
 
@@ -923,18 +1082,18 @@ Check the [Actions tab](../../actions) on GitHub to see the status of recent CI
 
 Add this badge to display CI status in your fork:
 
-```markdown
+```Markdown
 ![Tests](https://github.com/bitechdev/ResolveSpec/workflows/Tests/badge.svg)
 ```
 
 ## Security Considerations
 
-- Implement proper authentication and authorization
-- Validate all input parameters
-- Use prepared statements (handled by GORM/Bun/your ORM)
-- Implement rate limiting
-- Control access at schema/entity level
-- **New**: Database abstraction layer provides additional security through interface boundaries
+* Implement proper authentication and authorization
+* Validate all input parameters
+* Use prepared statements (handled by GORM/Bun/your ORM)
+* Implement rate limiting
+* Control access at schema/entity level
+* **New**: Database abstraction layer provides additional security through interface boundaries
 
 ## Contributing
 
@@ -946,73 +1105,114 @@ Add this badge to display CI status in your fork:
 
 ## License
 
-This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details. 
+This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details.
 
 ## What's New
 
-### v2.1 (Latest)
+### v3.0 (Latest - December 2025)
+
+**Explicit Route Registration (🆕)**:
+
+* **Breaking Change**: Routes are now created explicitly for each registered model
+* **Better Control**: Customize routes per model with more flexibility
+* **Registration Order**: Models must be registered BEFORE calling SetupMuxRoutes/SetupBunRouterRoutes
+* **Benefits**: More flexible routing, easier to add custom routes per model, better performance
+
+**OPTIONS Method & CORS Support (🆕)**:
+
+* **OPTIONS Endpoint**: Full OPTIONS method support for CORS preflight requests
+* **Metadata Response**: OPTIONS returns model metadata (same as GET /metadata)
+* **CORS Headers**: Comprehensive CORS headers on all responses
+* **Header Support**: All HeadSpec custom headers (`X-Select-Fields`, `X-FieldFilter-*`, etc.) allowed
+* **No Auth on OPTIONS**: CORS preflight requests don't require authentication
+* **Configurable**: Customize CORS settings via `common.CORSConfig`
+
+**Migration Notes**:
+
+* Update your code to register models BEFORE calling SetupMuxRoutes/SetupBunRouterRoutes
+* Routes like `/public/users` are now created per registered model instead of using dynamic `/{schema}/{entity}` pattern
+* This is a **breaking change** but provides better control and flexibility
+
+### v2.1
+
+**Cursor Pagination for ResolveSpec (🆕 Dec 9, 2025)**:
+
+* **Cursor-Based Pagination**: Efficient cursor pagination now available in ResolveSpec (body-based API)
+* **Consistent with RestHeadSpec**: Both APIs now support cursor pagination for feature parity
+* **Multi-Column Sort Support**: Works seamlessly with complex sorting requirements
+* **Better Performance**: Improved performance for large datasets compared to offset pagination
+* **SQL Safety**: Proper SQL sanitization for cursor values
 
 **Recursive CRUD Handler (🆕 Nov 11, 2025)**:
-- **Nested Object Graphs**: Automatically handle complex object hierarchies with parent-child relationships
-- **Foreign Key Resolution**: Automatic propagation of parent IDs to child records
-- **Per-Record Operations**: Control create/update/delete operations per record via `_request` field
-- **Transaction Safety**: All nested operations execute atomically within database transactions
-- **Relationship Detection**: Automatic detection of belongsTo, hasMany, hasOne, and many2many relationships
-- **Deep Nesting Support**: Handle relationships at any depth level
-- **Mixed Operations**: Combine insert, update, and delete operations in a single request
+
+* **Nested Object Graphs**: Automatically handle complex object hierarchies with parent-child relationships
+* **Foreign Key Resolution**: Automatic propagation of parent IDs to child records
+* **Per-Record Operations**: Control create/update/delete operations per record via `_request` field
+* **Transaction Safety**: All nested operations execute atomically within database transactions
+* **Relationship Detection**: Automatic detection of belongsTo, hasMany, hasOne, and many2many relationships
+* **Deep Nesting Support**: Handle relationships at any depth level
+* **Mixed Operations**: Combine insert, update, and delete operations in a single request
 
 **Primary Key Improvements (Nov 11, 2025)**:
-- **GetPrimaryKeyName**: Enhanced primary key detection for better preload and ID field handling
-- **Better GORM/Bun Support**: Improved compatibility with both ORMs for primary key operations
-- **Computed Column Support**: Fixed computed columns functionality across handlers
+
+* **GetPrimaryKeyName**: Enhanced primary key detection for better preload and ID field handling
+* **Better GORM/Bun Support**: Improved compatibility with both ORMs for primary key operations
+* **Computed Column Support**: Fixed computed columns functionality across handlers
 
 **Database Adapter Enhancements (Nov 11, 2025)**:
-- **Bun ORM Relations**: Using Scan model method for better has-many and many-to-many relationship handling
-- **Model Method Support**: Enhanced query building with proper model registration
-- **Improved Type Safety**: Better handling of relationship queries with type-aware scanning
+
+* **Bun ORM Relations**: Using Scan model method for better has-many and many-to-many relationship handling
+* **Model Method Support**: Enhanced query building with proper model registration
+* **Improved Type Safety**: Better handling of relationship queries with type-aware scanning
 
 **RestHeadSpec - Header-Based REST API**:
-- **Header-Based Querying**: All query options via HTTP headers instead of request body
-- **Lifecycle Hooks**: Before/after hooks for create, read, update, delete operations
-- **Cursor Pagination**: Efficient cursor-based pagination with complex sorting
-- **Advanced Filtering**: Field filters, search operators, AND/OR logic
-- **Multiple Response Formats**: Simple, detailed, and Syncfusion-compatible responses
-- **Single Record as Object**: Automatically return single-element arrays as objects (default, toggleable via header)
-- **Base64 Support**: Base64-encoded header values for complex queries
-- **Type-Aware Filtering**: Automatic type detection and conversion for filters
+
+* **Header-Based Querying**: All query options via HTTP headers instead of request body
+* **Lifecycle Hooks**: Before/after hooks for create, read, update, delete operations
+* **Cursor Pagination**: Efficient cursor-based pagination with complex sorting
+* **Advanced Filtering**: Field filters, search operators, AND/OR logic
+* **Multiple Response Formats**: Simple, detailed, and Syncfusion-compatible responses
+* **Single Record as Object**: Automatically return single-element arrays as objects (default, toggleable via header)
+* **Base64 Support**: Base64-encoded header values for complex queries
+* **Type-Aware Filtering**: Automatic type detection and conversion for filters
 
 **Core Improvements**:
-- Better model registry with schema.table format support
-- Enhanced validation and error handling
-- Improved reflection safety
-- Fixed COUNT query issues with table aliasing
-- Better pointer handling throughout the codebase
-- **Comprehensive Test Coverage**: Added standalone CRUD tests for both ResolveSpec and RestHeadSpec
+
+* Better model registry with schema.table format support
+* Enhanced validation and error handling
+* Improved reflection safety
+* Fixed COUNT query issues with table aliasing
+* Better pointer handling throughout the codebase
+* **Comprehensive Test Coverage**: Added standalone CRUD tests for both ResolveSpec and RestHeadSpec
 
 ### v2.0
 
 **Breaking Changes**:
-- **None!** Full backward compatibility maintained
+
+* **None!** Full backward compatibility maintained
 
 **New Features**:
-- **Database Abstraction**: Support for GORM, Bun, and custom ORMs
-- **Router Flexibility**: Works with any HTTP router through adapters
-- **BunRouter Integration**: Built-in support for uptrace/bunrouter
-- **Better Architecture**: Clean separation of concerns with interfaces
-- **Enhanced Testing**: Mockable interfaces for comprehensive testing
-- **Migration Guide**: Step-by-step migration instructions
+
+* **Database Abstraction**: Support for GORM, Bun, and custom ORMs
+* **Router Flexibility**: Works with any HTTP router through adapters
+* **BunRouter Integration**: Built-in support for uptrace/bunrouter
+* **Better Architecture**: Clean separation of concerns with interfaces
+* **Enhanced Testing**: Mockable interfaces for comprehensive testing
+* **Migration Guide**: Step-by-step migration instructions
 
 **Performance Improvements**:
-- More efficient query building through interface design
-- Reduced coupling between components
-- Better memory management with interface boundaries
+
+* More efficient query building through interface design
+* Reduced coupling between components
+* Better memory management with interface boundaries
 
 ## Acknowledgments
 
-- Inspired by REST, OData, and GraphQL's flexibility
-- **Header-based approach**: Inspired by REST best practices and clean API design
-- **Database Support**: [GORM](https://gorm.io) and [Bun](https://bun.uptrace.dev/)
-- **Router Support**: Gorilla Mux (built-in), BunRouter, Gin, Echo, and others through adapters
-- Slogan generated using DALL-E
-- AI used for documentation checking and correction
-- Community feedback and contributions that made v2.0 and v2.1 possible
+* Inspired by REST, OData, and GraphQL's flexibility
+* **Header-based approach**: Inspired by REST best practices and clean API design
+* **Database Support**: [GORM](https://gorm.io) and [Bun](https://bun.uptrace.dev/)
+* **Router Support**: Gorilla Mux (built-in), BunRouter, Gin, Echo, and others through adapters
+* Slogan generated using DALL-E
+* AI used for documentation checking and correction
+* Community feedback and contributions that made v2.0 and v2.1 possible
+

cmd/testserver/main.go

@@ -6,8 +6,10 @@ import (
 	"os"
 	"time"
 
+	"github.com/bitechdev/ResolveSpec/pkg/config"
 	"github.com/bitechdev/ResolveSpec/pkg/logger"
 	"github.com/bitechdev/ResolveSpec/pkg/modelregistry"
+	"github.com/bitechdev/ResolveSpec/pkg/server"
 	"github.com/bitechdev/ResolveSpec/pkg/testmodels"
 
 	"github.com/bitechdev/ResolveSpec/pkg/resolvespec"
@@ -19,12 +21,27 @@ import (
 )
 
 func main() {
-	// Initialize logger
-	logger.Init(true)
+	// Load configuration
+	cfgMgr := config.NewManager()
+	if err := cfgMgr.Load(); err != nil {
+		log.Fatalf("Failed to load configuration: %v", err)
+	}
+
+	cfg, err := cfgMgr.GetConfig()
+	if err != nil {
+		log.Fatalf("Failed to get configuration: %v", err)
+	}
+
+	// Initialize logger with configuration
+	logger.Init(cfg.Logger.Dev)
+	if cfg.Logger.Path != "" {
+		logger.UpdateLoggerPath(cfg.Logger.Path, cfg.Logger.Dev)
+	}
 	logger.Info("ResolveSpec test server starting")
+	logger.Info("Configuration loaded - Server will listen on: %s", cfg.Server.Addr)
 
 	// Initialize database
-	db, err := initDB()
+	db, err := initDB(cfg)
 	if err != nil {
 		logger.Error("Failed to initialize database: %+v", err)
 		os.Exit(1)
@@ -47,32 +64,54 @@ func main() {
 		handler.RegisterModel("public", modelNames[i], model)
 	}
 
-	// Setup routes using new SetupMuxRoutes function
-	resolvespec.SetupMuxRoutes(r, handler)
+	// Setup routes using new SetupMuxRoutes function (without authentication)
+	resolvespec.SetupMuxRoutes(r, handler, nil)
 
-	// Start server
-	logger.Info("Starting server on :8080")
-	if err := http.ListenAndServe(":8080", r); err != nil {
+	// Create graceful server with configuration
+	srv := server.NewGracefulServer(server.Config{
+		Addr:            cfg.Server.Addr,
+		Handler:         r,
+		ShutdownTimeout: cfg.Server.ShutdownTimeout,
+		DrainTimeout:    cfg.Server.DrainTimeout,
+		ReadTimeout:     cfg.Server.ReadTimeout,
+		WriteTimeout:    cfg.Server.WriteTimeout,
+		IdleTimeout:     cfg.Server.IdleTimeout,
+	})
+
+	// Start server with graceful shutdown
+	logger.Info("Starting server on %s", cfg.Server.Addr)
+	if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
 		logger.Error("Server failed to start: %v", err)
 		os.Exit(1)
 	}
 }
 
-func initDB() (*gorm.DB, error) {
+func initDB(cfg *config.Config) (*gorm.DB, error) {
+	// Configure GORM logger based on config
+	logLevel := gormlog.Info
+	if !cfg.Logger.Dev {
+		logLevel = gormlog.Warn
+	}
 
 	newLogger := gormlog.New(
 		log.New(os.Stdout, "\r\n", log.LstdFlags), // io writer
 		gormlog.Config{
-			SlowThreshold:             time.Second,  // Slow SQL threshold
-			LogLevel:                  gormlog.Info, // Log level
-			IgnoreRecordNotFoundError: true,         // Ignore ErrRecordNotFound error for logger
-			ParameterizedQueries:      true,         // Don't include params in the SQL log
-			Colorful:                  true,         // Disable color
+			SlowThreshold:             time.Second, // Slow SQL threshold
+			LogLevel:                  logLevel,    // Log level
+			IgnoreRecordNotFoundError: true,        // Ignore ErrRecordNotFound error for logger
+			ParameterizedQueries:      true,        // Don't include params in the SQL log
+			Colorful:                  cfg.Logger.Dev,
 		},
 	)
 
+	// Use database URL from config if available, otherwise use default SQLite
+	dbURL := cfg.Database.URL
+	if dbURL == "" {
+		dbURL = "test.db"
+	}
+
 	// Create SQLite database
-	db, err := gorm.Open(sqlite.Open("test.db"), &gorm.Config{Logger: newLogger, FullSaveAssociations: false})
+	db, err := gorm.Open(sqlite.Open(dbURL), &gorm.Config{Logger: newLogger, FullSaveAssociations: false})
 	if err != nil {
 		return nil, err
 	}

config.yaml

@@ -0,0 +1,41 @@
+# ResolveSpec Test Server Configuration
+# This is a minimal configuration for the test server
+
+server:
+  addr: ":8080"
+  shutdown_timeout: 30s
+  drain_timeout: 25s
+  read_timeout: 10s
+  write_timeout: 10s
+  idle_timeout: 120s
+
+logger:
+  dev: true  # Enable development mode for readable logs
+  path: ""   # Empty means log to stdout
+
+cache:
+  provider: "memory"
+
+middleware:
+  rate_limit_rps: 100.0
+  rate_limit_burst: 200
+  max_request_size: 10485760  # 10MB
+
+cors:
+  allowed_origins:
+    - "*"
+  allowed_methods:
+    - "GET"
+    - "POST"
+    - "PUT"
+    - "DELETE"
+    - "OPTIONS"
+  allowed_headers:
+    - "*"
+  max_age: 3600
+
+tracing:
+  enabled: false
+
+database:
+  url: ""  # Empty means use default SQLite (test.db)

config.yaml.example

@@ -0,0 +1,57 @@
+# ResolveSpec Configuration Example
+# This file demonstrates all available configuration options
+# Copy this file to config.yaml and customize as needed
+
+server:
+  addr: ":8080"
+  shutdown_timeout: 30s
+  drain_timeout: 25s
+  read_timeout: 10s
+  write_timeout: 10s
+  idle_timeout: 120s
+
+tracing:
+  enabled: false
+  service_name: "resolvespec"
+  service_version: "1.0.0"
+  endpoint: "http://localhost:4318/v1/traces"  # OTLP endpoint
+
+cache:
+  provider: "memory"  # Options: memory, redis, memcache
+
+  redis:
+    host: "localhost"
+    port: 6379
+    password: ""
+    db: 0
+
+  memcache:
+    servers:
+      - "localhost:11211"
+    max_idle_conns: 10
+    timeout: 100ms
+
+logger:
+  dev: false
+  path: ""  # Empty for stdout, or specify file path
+
+middleware:
+  rate_limit_rps: 100.0
+  rate_limit_burst: 200
+  max_request_size: 10485760  # 10MB in bytes
+
+cors:
+  allowed_origins:
+    - "*"
+  allowed_methods:
+    - "GET"
+    - "POST"
+    - "PUT"
+    - "DELETE"
+    - "OPTIONS"
+  allowed_headers:
+    - "*"
+  max_age: 3600
+
+database:
+  url: "host=localhost user=postgres password=postgres dbname=resolvespec_test port=5434 sslmode=disable"

docker-compose.yml

@@ -0,0 +1,27 @@
+services:
+  postgres-test:
+    image: postgres:15-alpine
+    container_name: resolvespec-postgres-test
+    environment:
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: postgres
+      POSTGRES_DB: postgres
+    ports:
+      - "5434:5432"
+    volumes:
+      - postgres-test-data:/var/lib/postgresql/data
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U postgres"]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+    networks:
+      - resolvespec-test
+
+volumes:
+  postgres-test-data:
+    driver: local
+
+networks:
+  resolvespec-test:
+    driver: bridge

go.mod

@@ -1,45 +1,93 @@
 module github.com/bitechdev/ResolveSpec
 
-go 1.23.0
+go 1.24.0
 
 toolchain go1.24.6
 
 require (
+	github.com/bradfitz/gomemcache v0.0.0-20250403215159-8d39553ac7cf
 	github.com/glebarez/sqlite v1.11.0
+	github.com/google/uuid v1.6.0
 	github.com/gorilla/mux v1.8.1
-	github.com/stretchr/testify v1.8.1
+	github.com/prometheus/client_golang v1.23.2
+	github.com/redis/go-redis/v9 v9.17.1
+	github.com/stretchr/testify v1.11.1
 	github.com/tidwall/gjson v1.18.0
 	github.com/tidwall/sjson v1.2.5
 	github.com/uptrace/bun v1.2.15
 	github.com/uptrace/bun/dialect/sqlitedialect v1.2.15
 	github.com/uptrace/bun/driver/sqliteshim v1.2.15
 	github.com/uptrace/bunrouter v1.0.23
+	go.opentelemetry.io/otel v1.38.0
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.38.0
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.38.0
+	go.opentelemetry.io/otel/sdk v1.38.0
+	go.opentelemetry.io/otel/trace v1.38.0
 	go.uber.org/zap v1.27.0
+	golang.org/x/time v0.14.0
+	gorm.io/driver/postgres v1.6.0
 	gorm.io/gorm v1.25.12
 )
 
 require (
+	github.com/DATA-DOG/go-sqlmock v1.5.2 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cenkalti/backoff/v5 v5.0.3 // indirect
+	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
+	github.com/fsnotify/fsnotify v1.9.0 // indirect
 	github.com/glebarez/go-sqlite v1.21.2 // indirect
-	github.com/google/uuid v1.6.0 // indirect
+	github.com/go-logr/logr v1.4.3 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/go-viper/mapstructure/v2 v2.4.0 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.2 // indirect
+	github.com/jackc/pgpassfile v1.0.0 // indirect
+	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
+	github.com/jackc/pgx/v5 v5.6.0 // indirect
+	github.com/jackc/puddle/v2 v2.2.2 // indirect
 	github.com/jinzhu/inflection v1.0.0 // indirect
 	github.com/jinzhu/now v1.1.5 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mattn/go-sqlite3 v1.14.28 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/ncruces/go-strftime v0.1.9 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.4 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/prometheus/client_model v0.6.2 // indirect
+	github.com/prometheus/common v0.66.1 // indirect
+	github.com/prometheus/procfs v0.16.1 // indirect
 	github.com/puzpuzpuz/xsync/v3 v3.5.1 // indirect
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
+	github.com/sagikazarmark/locafero v0.11.0 // indirect
+	github.com/sourcegraph/conc v0.3.1-0.20240121214520-5f936abd7ae8 // indirect
+	github.com/spf13/afero v1.15.0 // indirect
+	github.com/spf13/cast v1.10.0 // indirect
+	github.com/spf13/pflag v1.0.10 // indirect
+	github.com/spf13/viper v1.21.0 // indirect
+	github.com/subosito/gotenv v1.6.0 // indirect
 	github.com/tidwall/match v1.1.1 // indirect
 	github.com/tidwall/pretty v1.2.0 // indirect
 	github.com/tmthrgd/go-hex v0.0.0-20190904060850-447a3041c3bc // indirect
 	github.com/vmihailenco/msgpack/v5 v5.4.1 // indirect
 	github.com/vmihailenco/tagparser/v2 v2.0.0 // indirect
+	go.opentelemetry.io/auto/sdk v1.1.0 // indirect
+	go.opentelemetry.io/otel/metric v1.38.0 // indirect
+	go.opentelemetry.io/proto/otlp v1.7.1 // indirect
 	go.uber.org/multierr v1.10.0 // indirect
+	go.yaml.in/yaml/v2 v2.4.2 // indirect
+	go.yaml.in/yaml/v3 v3.0.4 // indirect
+	golang.org/x/crypto v0.41.0 // indirect
 	golang.org/x/exp v0.0.0-20250711185948-6ae5c78190dc // indirect
-	golang.org/x/sys v0.34.0 // indirect
-	golang.org/x/text v0.21.0 // indirect
+	golang.org/x/net v0.43.0 // indirect
+	golang.org/x/sync v0.16.0 // indirect
+	golang.org/x/sys v0.35.0 // indirect
+	golang.org/x/text v0.28.0 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20250825161204-c5933d9347a5 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20250825161204-c5933d9347a5 // indirect
+	google.golang.org/grpc v1.75.0 // indirect
+	google.golang.org/protobuf v1.36.8 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	modernc.org/libc v1.66.3 // indirect
 	modernc.org/mathutil v1.7.1 // indirect

go.sum

@@ -1,45 +1,117 @@
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@@ -63,31 +135,71 @@ github.com/vmihailenco/msgpack/v5 v5.4.1 h1:cQriyiUvjTwOHg8QZaPihLWeRAAVoCpE00IU
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pkg/cache/README.md

@@ -0,0 +1,340 @@
+# Cache Package
+
+A flexible, provider-based caching library for Go that supports multiple backend storage systems including in-memory, Redis, and Memcache.
+
+## Features
+
+- **Multiple Providers**: Support for in-memory, Redis, and Memcache backends
+- **Pluggable Architecture**: Easy to add custom cache providers
+- **Type-Safe API**: Automatic JSON serialization/deserialization
+- **TTL Support**: Configurable time-to-live for cache entries
+- **Context-Aware**: All operations support Go contexts
+- **Statistics**: Built-in cache statistics and monitoring
+- **Pattern Deletion**: Delete keys by pattern (Redis)
+- **Lazy Loading**: GetOrSet pattern for easy cache-aside implementation
+
+## Installation
+
+```bash
+go get github.com/bitechdev/ResolveSpec/pkg/cache
+```
+
+For Redis support:
+```bash
+go get github.com/redis/go-redis/v9
+```
+
+For Memcache support:
+```bash
+go get github.com/bradfitz/gomemcache/memcache
+```
+
+## Quick Start
+
+### In-Memory Cache
+
+```go
+package main
+
+import (
+    "context"
+    "time"
+    "github.com/bitechdev/ResolveSpec/pkg/cache"
+)
+
+func main() {
+    // Initialize with in-memory provider
+    cache.UseMemory(&cache.Options{
+        DefaultTTL: 5 * time.Minute,
+        MaxSize:    10000,
+    })
+    defer cache.Close()
+
+    ctx := context.Background()
+    c := cache.GetDefaultCache()
+
+    // Store a value
+    type User struct {
+        ID   int
+        Name string
+    }
+    user := User{ID: 1, Name: "John"}
+    c.Set(ctx, "user:1", user, 10*time.Minute)
+
+    // Retrieve a value
+    var retrieved User
+    c.Get(ctx, "user:1", &retrieved)
+}
+```
+
+### Redis Cache
+
+```go
+cache.UseRedis(&cache.RedisConfig{
+    Host:     "localhost",
+    Port:     6379,
+    Password: "",
+    DB:       0,
+    Options: &cache.Options{
+        DefaultTTL: 5 * time.Minute,
+    },
+})
+defer cache.Close()
+```
+
+### Memcache
+
+```go
+cache.UseMemcache(&cache.MemcacheConfig{
+    Servers: []string{"localhost:11211"},
+    Options: &cache.Options{
+        DefaultTTL: 5 * time.Minute,
+    },
+})
+defer cache.Close()
+```
+
+## API Reference
+
+### Core Methods
+
+#### Set
+```go
+Set(ctx context.Context, key string, value interface{}, ttl time.Duration) error
+```
+Stores a value in the cache with automatic JSON serialization.
+
+#### Get
+```go
+Get(ctx context.Context, key string, dest interface{}) error
+```
+Retrieves and deserializes a value from the cache.
+
+#### SetBytes / GetBytes
+```go
+SetBytes(ctx context.Context, key string, value []byte, ttl time.Duration) error
+GetBytes(ctx context.Context, key string) ([]byte, error)
+```
+Store and retrieve raw bytes without serialization.
+
+#### Delete
+```go
+Delete(ctx context.Context, key string) error
+```
+Removes a key from the cache.
+
+#### DeleteByPattern
+```go
+DeleteByPattern(ctx context.Context, pattern string) error
+```
+Removes all keys matching a pattern (Redis only).
+
+#### Clear
+```go
+Clear(ctx context.Context) error
+```
+Removes all items from the cache.
+
+#### Exists
+```go
+Exists(ctx context.Context, key string) bool
+```
+Checks if a key exists in the cache.
+
+#### GetOrSet
+```go
+GetOrSet(ctx context.Context, key string, dest interface{}, ttl time.Duration,
+         loader func() (interface{}, error)) error
+```
+Retrieves a value from cache, or loads and caches it if not found (lazy loading).
+
+#### Stats
+```go
+Stats(ctx context.Context) (*CacheStats, error)
+```
+Returns cache statistics including hits, misses, and key counts.
+
+## Provider Configuration
+
+### In-Memory Options
+
+```go
+&cache.Options{
+    DefaultTTL:     5 * time.Minute,  // Default expiration time
+    MaxSize:        10000,             // Maximum number of items
+    EvictionPolicy: "LRU",             // Eviction strategy (future)
+}
+```
+
+### Redis Configuration
+
+```go
+&cache.RedisConfig{
+    Host:     "localhost",
+    Port:     6379,
+    Password: "",         // Optional authentication
+    DB:       0,          // Database number
+    PoolSize: 10,         // Connection pool size
+    Options:  &cache.Options{
+        DefaultTTL: 5 * time.Minute,
+    },
+}
+```
+
+### Memcache Configuration
+
+```go
+&cache.MemcacheConfig{
+    Servers:      []string{"localhost:11211"},
+    MaxIdleConns: 2,
+    Timeout:      1 * time.Second,
+    Options: &cache.Options{
+        DefaultTTL: 5 * time.Minute,
+    },
+}
+```
+
+## Advanced Usage
+
+### Custom Provider
+
+```go
+// Create a custom provider instance
+memProvider := cache.NewMemoryProvider(&cache.Options{
+    DefaultTTL: 10 * time.Minute,
+    MaxSize:    500,
+})
+
+// Initialize with custom provider
+cache.Initialize(memProvider)
+```
+
+### Lazy Loading Pattern
+
+```go
+var data ExpensiveData
+err := c.GetOrSet(ctx, "expensive:key", &data, 10*time.Minute, func() (interface{}, error) {
+    // This expensive operation only runs if key is not in cache
+    return computeExpensiveData(), nil
+})
+```
+
+### Query API Cache
+
+The package includes specialized functions for caching query results:
+
+```go
+// Cache a query result
+api := "GetUsers"
+query := "SELECT * FROM users WHERE active = true"
+tablenames := "users"
+total := int64(150)
+
+cache.PutQueryAPICache(ctx, api, query, tablenames, total)
+
+// Retrieve cached query
+hash := cache.HashQueryAPICache(api, query)
+cachedQuery, err := cache.FetchQueryAPICache(ctx, hash)
+```
+
+## Provider Comparison
+
+| Feature | In-Memory | Redis | Memcache |
+|---------|-----------|-------|----------|
+| Persistence | No | Yes | No |
+| Distributed | No | Yes | Yes |
+| Pattern Delete | No | Yes | No |
+| Statistics | Full | Full | Limited |
+| Atomic Operations | Yes | Yes | Yes |
+| Max Item Size | Memory | 512MB | 1MB |
+
+## Best Practices
+
+1. **Use contexts**: Always pass context for cancellation and timeout control
+2. **Set appropriate TTLs**: Balance between freshness and performance
+3. **Handle errors**: Cache misses and errors should be handled gracefully
+4. **Monitor statistics**: Use Stats() to monitor cache performance
+5. **Clean up**: Always call Close() when shutting down
+6. **Pattern consistency**: Use consistent key naming patterns (e.g., "user:id:field")
+
+## Example: Complete Application
+
+```go
+package main
+
+import (
+    "context"
+    "log"
+    "time"
+    "github.com/bitechdev/ResolveSpec/pkg/cache"
+)
+
+type UserService struct {
+    cache *cache.Cache
+}
+
+func NewUserService() *UserService {
+    // Initialize with Redis in production, memory for testing
+    cache.UseRedis(&cache.RedisConfig{
+        Host: "localhost",
+        Port: 6379,
+        Options: &cache.Options{
+            DefaultTTL: 10 * time.Minute,
+        },
+    })
+
+    return &UserService{
+        cache: cache.GetDefaultCache(),
+    }
+}
+
+func (s *UserService) GetUser(ctx context.Context, userID int) (*User, error) {
+    var user User
+    cacheKey := fmt.Sprintf("user:%d", userID)
+
+    // Try to get from cache first
+    err := s.cache.GetOrSet(ctx, cacheKey, &user, 15*time.Minute, func() (interface{}, error) {
+        // Load from database if not in cache
+        return s.loadUserFromDB(userID)
+    })
+
+    if err != nil {
+        return nil, err
+    }
+
+    return &user, nil
+}
+
+func (s *UserService) InvalidateUser(ctx context.Context, userID int) error {
+    cacheKey := fmt.Sprintf("user:%d", userID)
+    return s.cache.Delete(ctx, cacheKey)
+}
+
+func main() {
+    service := NewUserService()
+    defer cache.Close()
+
+    ctx := context.Background()
+    user, err := service.GetUser(ctx, 123)
+    if err != nil {
+        log.Fatal(err)
+    }
+
+    log.Printf("User: %+v", user)
+}
+```
+
+## Performance Considerations
+
+- **In-Memory**: Fastest but limited by RAM and not distributed
+- **Redis**: Great for distributed systems, persistent, but network overhead
+- **Memcache**: Good for distributed caching, simpler than Redis but less features
+
+Choose based on your needs:
+- Single instance? Use in-memory
+- Need persistence or advanced features? Use Redis
+- Simple distributed cache? Use Memcache
+
+## License
+
+See repository license.

pkg/cache/cache.go

@@ -0,0 +1,76 @@
+package cache
+
+import (
+	"context"
+	"fmt"
+	"time"
+)
+
+var (
+	defaultCache *Cache
+)
+
+// Initialize initializes the cache with a provider.
+// If not called, the package will use an in-memory provider by default.
+func Initialize(provider Provider) {
+	defaultCache = NewCache(provider)
+}
+
+// UseMemory configures the cache to use in-memory storage.
+func UseMemory(opts *Options) error {
+	provider := NewMemoryProvider(opts)
+	defaultCache = NewCache(provider)
+	return nil
+}
+
+// UseRedis configures the cache to use Redis storage.
+func UseRedis(config *RedisConfig) error {
+	provider, err := NewRedisProvider(config)
+	if err != nil {
+		return fmt.Errorf("failed to initialize Redis provider: %w", err)
+	}
+	defaultCache = NewCache(provider)
+	return nil
+}
+
+// UseMemcache configures the cache to use Memcache storage.
+func UseMemcache(config *MemcacheConfig) error {
+	provider, err := NewMemcacheProvider(config)
+	if err != nil {
+		return fmt.Errorf("failed to initialize Memcache provider: %w", err)
+	}
+	defaultCache = NewCache(provider)
+	return nil
+}
+
+// GetDefaultCache returns the default cache instance.
+// Initializes with in-memory provider if not already initialized.
+func GetDefaultCache() *Cache {
+	if defaultCache == nil {
+		_ = UseMemory(&Options{
+			DefaultTTL: 5 * time.Minute,
+			MaxSize:    10000,
+		})
+	}
+	return defaultCache
+}
+
+// SetDefaultCache sets a custom cache instance as the default cache.
+// This is useful for testing or when you want to use a pre-configured cache instance.
+func SetDefaultCache(cache *Cache) {
+	defaultCache = cache
+}
+
+// GetStats returns cache statistics.
+func GetStats(ctx context.Context) (*CacheStats, error) {
+	cache := GetDefaultCache()
+	return cache.Stats(ctx)
+}
+
+// Close closes the cache and releases resources.
+func Close() error {
+	if defaultCache != nil {
+		return defaultCache.Close()
+	}
+	return nil
+}

pkg/cache/cache_manager.go

@@ -0,0 +1,147 @@
+package cache
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+// Cache is the main cache manager that wraps a Provider.
+type Cache struct {
+	provider Provider
+}
+
+// NewCache creates a new cache manager with the specified provider.
+func NewCache(provider Provider) *Cache {
+	return &Cache{
+		provider: provider,
+	}
+}
+
+// Get retrieves and deserializes a value from the cache.
+func (c *Cache) Get(ctx context.Context, key string, dest interface{}) error {
+	data, exists := c.provider.Get(ctx, key)
+	if !exists {
+		return fmt.Errorf("key not found: %s", key)
+	}
+
+	if err := json.Unmarshal(data, dest); err != nil {
+		return fmt.Errorf("failed to deserialize: %w", err)
+	}
+
+	return nil
+}
+
+// GetBytes retrieves raw bytes from the cache.
+func (c *Cache) GetBytes(ctx context.Context, key string) ([]byte, error) {
+	data, exists := c.provider.Get(ctx, key)
+	if !exists {
+		return nil, fmt.Errorf("key not found: %s", key)
+	}
+	return data, nil
+}
+
+// Set serializes and stores a value in the cache with the specified TTL.
+func (c *Cache) Set(ctx context.Context, key string, value interface{}, ttl time.Duration) error {
+	data, err := json.Marshal(value)
+	if err != nil {
+		return fmt.Errorf("failed to serialize: %w", err)
+	}
+
+	return c.provider.Set(ctx, key, data, ttl)
+}
+
+// SetBytes stores raw bytes in the cache with the specified TTL.
+func (c *Cache) SetBytes(ctx context.Context, key string, value []byte, ttl time.Duration) error {
+	return c.provider.Set(ctx, key, value, ttl)
+}
+
+// Delete removes a key from the cache.
+func (c *Cache) Delete(ctx context.Context, key string) error {
+	return c.provider.Delete(ctx, key)
+}
+
+// DeleteByPattern removes all keys matching the pattern.
+func (c *Cache) DeleteByPattern(ctx context.Context, pattern string) error {
+	return c.provider.DeleteByPattern(ctx, pattern)
+}
+
+// Clear removes all items from the cache.
+func (c *Cache) Clear(ctx context.Context) error {
+	return c.provider.Clear(ctx)
+}
+
+// Exists checks if a key exists in the cache.
+func (c *Cache) Exists(ctx context.Context, key string) bool {
+	return c.provider.Exists(ctx, key)
+}
+
+// Stats returns statistics about the cache.
+func (c *Cache) Stats(ctx context.Context) (*CacheStats, error) {
+	return c.provider.Stats(ctx)
+}
+
+// Close closes the cache and releases any resources.
+func (c *Cache) Close() error {
+	return c.provider.Close()
+}
+
+// GetOrSet retrieves a value from cache, or sets it if it doesn't exist.
+// The loader function is called only if the key is not found in cache.
+func (c *Cache) GetOrSet(ctx context.Context, key string, dest interface{}, ttl time.Duration, loader func() (interface{}, error)) error {
+	// Try to get from cache first
+	err := c.Get(ctx, key, dest)
+	if err == nil {
+		return nil
+	}
+
+	// Load the value
+	value, err := loader()
+	if err != nil {
+		return fmt.Errorf("loader failed: %w", err)
+	}
+
+	// Store in cache
+	if err := c.Set(ctx, key, value, ttl); err != nil {
+		return fmt.Errorf("failed to cache value: %w", err)
+	}
+
+	// Populate dest with the loaded value
+	data, err := json.Marshal(value)
+	if err != nil {
+		return fmt.Errorf("failed to serialize loaded value: %w", err)
+	}
+
+	if err := json.Unmarshal(data, dest); err != nil {
+		return fmt.Errorf("failed to deserialize loaded value: %w", err)
+	}
+
+	return nil
+}
+
+// Remember is a convenience function that caches the result of a function call.
+// It's similar to GetOrSet but returns the value directly.
+func (c *Cache) Remember(ctx context.Context, key string, ttl time.Duration, loader func() (interface{}, error)) (interface{}, error) {
+	// Try to get from cache first as bytes
+	data, err := c.GetBytes(ctx, key)
+	if err == nil {
+		var result interface{}
+		if err := json.Unmarshal(data, &result); err == nil {
+			return result, nil
+		}
+	}
+
+	// Load the value
+	value, err := loader()
+	if err != nil {
+		return nil, fmt.Errorf("loader failed: %w", err)
+	}
+
+	// Store in cache
+	if err := c.Set(ctx, key, value, ttl); err != nil {
+		return nil, fmt.Errorf("failed to cache value: %w", err)
+	}
+
+	return value, nil
+}

pkg/cache/cache_test.go

@@ -0,0 +1,69 @@
+package cache
+
+import (
+	"context"
+	"testing"
+	"time"
+)
+
+func TestSetDefaultCache(t *testing.T) {
+	// Create a custom cache instance
+	provider := NewMemoryProvider(&Options{
+		DefaultTTL: 1 * time.Minute,
+		MaxSize:    50,
+	})
+	customCache := NewCache(provider)
+
+	// Set it as the default
+	SetDefaultCache(customCache)
+
+	// Verify it's now the default
+	retrievedCache := GetDefaultCache()
+	if retrievedCache != customCache {
+		t.Error("SetDefaultCache did not set the cache correctly")
+	}
+
+	// Test that we can use it
+	ctx := context.Background()
+	testKey := "test_key"
+	testValue := "test_value"
+
+	err := retrievedCache.Set(ctx, testKey, testValue, time.Minute)
+	if err != nil {
+		t.Fatalf("Failed to set value: %v", err)
+	}
+
+	var result string
+	err = retrievedCache.Get(ctx, testKey, &result)
+	if err != nil {
+		t.Fatalf("Failed to get value: %v", err)
+	}
+
+	if result != testValue {
+		t.Errorf("Expected %s, got %s", testValue, result)
+	}
+
+	// Clean up - reset to default
+	SetDefaultCache(nil)
+}
+
+func TestGetDefaultCacheInitialization(t *testing.T) {
+	// Reset to nil first
+	SetDefaultCache(nil)
+
+	// GetDefaultCache should auto-initialize
+	cache := GetDefaultCache()
+	if cache == nil {
+		t.Error("GetDefaultCache should auto-initialize, got nil")
+	}
+
+	// Should be usable
+	ctx := context.Background()
+	err := cache.Set(ctx, "test", "value", time.Minute)
+	if err != nil {
+		t.Errorf("Failed to use auto-initialized cache: %v", err)
+	}
+
+	// Clean up
+	SetDefaultCache(nil)
+}

pkg/cache/example_usage.go

@@ -0,0 +1,266 @@
+package cache
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"time"
+)
+
+// ExampleInMemoryCache demonstrates using the in-memory cache provider.
+func ExampleInMemoryCache() {
+	// Initialize with in-memory provider
+	err := UseMemory(&Options{
+		DefaultTTL: 5 * time.Minute,
+		MaxSize:    1000,
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	ctx := context.Background()
+
+	// Get the cache instance
+	cache := GetDefaultCache()
+
+	// Store a value
+	type User struct {
+		ID   int
+		Name string
+	}
+
+	user := User{ID: 1, Name: "John Doe"}
+	err = cache.Set(ctx, "user:1", user, 10*time.Minute)
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+
+	// Retrieve a value
+	var retrieved User
+	err = cache.Get(ctx, "user:1", &retrieved)
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+
+	fmt.Printf("Retrieved user: %+v\n", retrieved)
+
+	// Check if key exists
+	exists := cache.Exists(ctx, "user:1")
+	fmt.Printf("Key exists: %v\n", exists)
+
+	// Delete a key
+	err = cache.Delete(ctx, "user:1")
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+
+	// Get statistics
+	stats, err := cache.Stats(ctx)
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+	fmt.Printf("Cache stats: %+v\n", stats)
+	_ = Close()
+}
+
+// ExampleRedisCache demonstrates using the Redis cache provider.
+func ExampleRedisCache() {
+	// Initialize with Redis provider
+	err := UseRedis(&RedisConfig{
+		Host:     "localhost",
+		Port:     6379,
+		Password: "", // Set if Redis requires authentication
+		DB:       0,
+		Options: &Options{
+			DefaultTTL: 5 * time.Minute,
+		},
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	ctx := context.Background()
+
+	// Get the cache instance
+	cache := GetDefaultCache()
+
+	// Store raw bytes
+	data := []byte("Hello, Redis!")
+	err = cache.SetBytes(ctx, "greeting", data, 1*time.Hour)
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+
+	// Retrieve raw bytes
+	retrieved, err := cache.GetBytes(ctx, "greeting")
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+
+	fmt.Printf("Retrieved data: %s\n", string(retrieved))
+
+	// Clear all cache
+	err = cache.Clear(ctx)
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+	_ = Close()
+}
+
+// ExampleMemcacheCache demonstrates using the Memcache cache provider.
+func ExampleMemcacheCache() {
+	// Initialize with Memcache provider
+	err := UseMemcache(&MemcacheConfig{
+		Servers: []string{"localhost:11211"},
+		Options: &Options{
+			DefaultTTL: 5 * time.Minute,
+		},
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	ctx := context.Background()
+
+	// Get the cache instance
+	cache := GetDefaultCache()
+
+	// Store a value
+	type Product struct {
+		ID    int
+		Name  string
+		Price float64
+	}
+
+	product := Product{ID: 100, Name: "Widget", Price: 29.99}
+	err = cache.Set(ctx, "product:100", product, 30*time.Minute)
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+
+	// Retrieve a value
+	var retrieved Product
+	err = cache.Get(ctx, "product:100", &retrieved)
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+
+	fmt.Printf("Retrieved product: %+v\n", retrieved)
+	_ = Close()
+}
+
+// ExampleGetOrSet demonstrates the GetOrSet pattern for lazy loading.
+func ExampleGetOrSet() {
+	err := UseMemory(&Options{
+		DefaultTTL: 5 * time.Minute,
+		MaxSize:    1000,
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	ctx := context.Background()
+	cache := GetDefaultCache()
+
+	type ExpensiveData struct {
+		Result string
+	}
+
+	var data ExpensiveData
+	err = cache.GetOrSet(ctx, "expensive:computation", &data, 10*time.Minute, func() (interface{}, error) {
+		// This expensive operation only runs if the key is not in cache
+		fmt.Println("Computing expensive result...")
+		time.Sleep(1 * time.Second)
+		return ExpensiveData{Result: "computed value"}, nil
+	})
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+
+	fmt.Printf("Data: %+v\n", data)
+
+	// Second call will use cached value
+	err = cache.GetOrSet(ctx, "expensive:computation", &data, 10*time.Minute, func() (interface{}, error) {
+		fmt.Println("This won't be called!")
+		return ExpensiveData{Result: "new value"}, nil
+	})
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+
+	fmt.Printf("Cached data: %+v\n", data)
+	_ = Close()
+}
+
+// ExampleCustomProvider demonstrates using a custom provider.
+func ExampleCustomProvider() {
+	// Create a custom provider
+	memProvider := NewMemoryProvider(&Options{
+		DefaultTTL: 10 * time.Minute,
+		MaxSize:    500,
+	})
+
+	// Initialize with custom provider
+	Initialize(memProvider)
+
+	ctx := context.Background()
+	cache := GetDefaultCache()
+
+	// Use the cache
+	err := cache.SetBytes(ctx, "key", []byte("value"), 5*time.Minute)
+	if err != nil {
+		_ = Close()
+		log.Fatal(err)
+	}
+
+	// Clean expired items (memory provider specific)
+	if mp, ok := cache.provider.(*MemoryProvider); ok {
+		count := mp.CleanExpired(ctx)
+		fmt.Printf("Cleaned %d expired items\n", count)
+	}
+	_ = Close()
+}
+
+// ExampleDeleteByPattern demonstrates pattern-based deletion (Redis only).
+func ExampleDeleteByPattern() {
+	err := UseRedis(&RedisConfig{
+		Host: "localhost",
+		Port: 6379,
+		Options: &Options{
+			DefaultTTL: 5 * time.Minute,
+		},
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	ctx := context.Background()
+	cache := GetDefaultCache()
+
+	// Store multiple keys with a pattern
+	_ = cache.SetBytes(ctx, "user:1:profile", []byte("profile1"), 10*time.Minute)
+	_ = cache.SetBytes(ctx, "user:2:profile", []byte("profile2"), 10*time.Minute)
+	_ = cache.SetBytes(ctx, "user:1:settings", []byte("settings1"), 10*time.Minute)
+
+	// Delete all keys matching pattern (Redis glob pattern)
+	err = cache.DeleteByPattern(ctx, "user:*:profile")
+	if err != nil {
+		_ = Close()
+		log.Print(err)
+		return
+	}
+
+	fmt.Println("Deleted all user profile keys")
+	_ = Close()
+}

pkg/cache/provider.go

@@ -0,0 +1,57 @@
+package cache
+
+import (
+	"context"
+	"time"
+)
+
+// Provider defines the interface that all cache providers must implement.
+type Provider interface {
+	// Get retrieves a value from the cache by key.
+	// Returns nil, false if key doesn't exist or is expired.
+	Get(ctx context.Context, key string) ([]byte, bool)
+
+	// Set stores a value in the cache with the specified TTL.
+	// If ttl is 0, the item never expires.
+	Set(ctx context.Context, key string, value []byte, ttl time.Duration) error
+
+	// Delete removes a key from the cache.
+	Delete(ctx context.Context, key string) error
+
+	// DeleteByPattern removes all keys matching the pattern.
+	// Pattern syntax depends on the provider implementation.
+	DeleteByPattern(ctx context.Context, pattern string) error
+
+	// Clear removes all items from the cache.
+	Clear(ctx context.Context) error
+
+	// Exists checks if a key exists in the cache.
+	Exists(ctx context.Context, key string) bool
+
+	// Close closes the provider and releases any resources.
+	Close() error
+
+	// Stats returns statistics about the cache provider.
+	Stats(ctx context.Context) (*CacheStats, error)
+}
+
+// CacheStats contains cache statistics.
+type CacheStats struct {
+	Hits          int64          `json:"hits"`
+	Misses        int64          `json:"misses"`
+	Keys          int64          `json:"keys"`
+	ProviderType  string         `json:"provider_type"`
+	ProviderStats map[string]any `json:"provider_stats,omitempty"`
+}
+
+// Options contains configuration options for cache providers.
+type Options struct {
+	// DefaultTTL is the default time-to-live for cache items.
+	DefaultTTL time.Duration
+
+	// MaxSize is the maximum number of items (for in-memory provider).
+	MaxSize int
+
+	// EvictionPolicy determines how items are evicted (LRU, LFU, etc).
+	EvictionPolicy string
+}

pkg/cache/provider_memcache.go

@@ -0,0 +1,144 @@
+package cache
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/bradfitz/gomemcache/memcache"
+)
+
+// MemcacheProvider is a Memcache implementation of the Provider interface.
+type MemcacheProvider struct {
+	client  *memcache.Client
+	options *Options
+}
+
+// MemcacheConfig contains Memcache-specific configuration.
+type MemcacheConfig struct {
+	// Servers is a list of memcache server addresses (e.g., "localhost:11211")
+	Servers []string
+
+	// MaxIdleConns is the maximum number of idle connections (default: 2)
+	MaxIdleConns int
+
+	// Timeout for connection operations (default: 1 second)
+	Timeout time.Duration
+
+	// Options contains general cache options
+	Options *Options
+}
+
+// NewMemcacheProvider creates a new Memcache cache provider.
+func NewMemcacheProvider(config *MemcacheConfig) (*MemcacheProvider, error) {
+	if config == nil {
+		config = &MemcacheConfig{
+			Servers: []string{"localhost:11211"},
+		}
+	}
+
+	if len(config.Servers) == 0 {
+		config.Servers = []string{"localhost:11211"}
+	}
+
+	if config.MaxIdleConns == 0 {
+		config.MaxIdleConns = 2
+	}
+
+	if config.Timeout == 0 {
+		config.Timeout = 1 * time.Second
+	}
+
+	if config.Options == nil {
+		config.Options = &Options{
+			DefaultTTL: 5 * time.Minute,
+		}
+	}
+
+	client := memcache.New(config.Servers...)
+	client.MaxIdleConns = config.MaxIdleConns
+	client.Timeout = config.Timeout
+
+	// Test connection
+	if err := client.Ping(); err != nil {
+		return nil, fmt.Errorf("failed to connect to Memcache: %w", err)
+	}
+
+	return &MemcacheProvider{
+		client:  client,
+		options: config.Options,
+	}, nil
+}
+
+// Get retrieves a value from the cache by key.
+func (m *MemcacheProvider) Get(ctx context.Context, key string) ([]byte, bool) {
+	item, err := m.client.Get(key)
+	if err == memcache.ErrCacheMiss {
+		return nil, false
+	}
+	if err != nil {
+		return nil, false
+	}
+	return item.Value, true
+}
+
+// Set stores a value in the cache with the specified TTL.
+func (m *MemcacheProvider) Set(ctx context.Context, key string, value []byte, ttl time.Duration) error {
+	if ttl == 0 {
+		ttl = m.options.DefaultTTL
+	}
+
+	item := &memcache.Item{
+		Key:        key,
+		Value:      value,
+		Expiration: int32(ttl.Seconds()),
+	}
+
+	return m.client.Set(item)
+}
+
+// Delete removes a key from the cache.
+func (m *MemcacheProvider) Delete(ctx context.Context, key string) error {
+	err := m.client.Delete(key)
+	if err == memcache.ErrCacheMiss {
+		return nil
+	}
+	return err
+}
+
+// DeleteByPattern removes all keys matching the pattern.
+// Note: Memcache does not support pattern-based deletion natively.
+// This is a no-op for memcache and returns an error.
+func (m *MemcacheProvider) DeleteByPattern(ctx context.Context, pattern string) error {
+	return fmt.Errorf("pattern-based deletion is not supported by Memcache")
+}
+
+// Clear removes all items from the cache.
+func (m *MemcacheProvider) Clear(ctx context.Context) error {
+	return m.client.FlushAll()
+}
+
+// Exists checks if a key exists in the cache.
+func (m *MemcacheProvider) Exists(ctx context.Context, key string) bool {
+	_, err := m.client.Get(key)
+	return err == nil
+}
+
+// Close closes the provider and releases any resources.
+func (m *MemcacheProvider) Close() error {
+	// Memcache client doesn't have a close method
+	return nil
+}
+
+// Stats returns statistics about the cache provider.
+// Note: Memcache provider returns limited statistics.
+func (m *MemcacheProvider) Stats(ctx context.Context) (*CacheStats, error) {
+	stats := &CacheStats{
+		ProviderType: "memcache",
+		ProviderStats: map[string]any{
+			"note": "Memcache does not provide detailed statistics through the standard client",
+		},
+	}
+
+	return stats, nil
+}

pkg/cache/provider_memory.go

@@ -0,0 +1,238 @@
+package cache
+
+import (
+	"context"
+	"fmt"
+	"regexp"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// memoryItem represents a cached item in memory.
+type memoryItem struct {
+	Value      []byte
+	Expiration time.Time
+	LastAccess time.Time
+	HitCount   int64
+}
+
+// isExpired checks if the item has expired.
+func (m *memoryItem) isExpired() bool {
+	if m.Expiration.IsZero() {
+		return false
+	}
+	return time.Now().After(m.Expiration)
+}
+
+// MemoryProvider is an in-memory implementation of the Provider interface.
+type MemoryProvider struct {
+	mu      sync.RWMutex
+	items   map[string]*memoryItem
+	options *Options
+	hits    atomic.Int64
+	misses  atomic.Int64
+}
+
+// NewMemoryProvider creates a new in-memory cache provider.
+func NewMemoryProvider(opts *Options) *MemoryProvider {
+	if opts == nil {
+		opts = &Options{
+			DefaultTTL: 5 * time.Minute,
+			MaxSize:    10000,
+		}
+	}
+
+	return &MemoryProvider{
+		items:   make(map[string]*memoryItem),
+		options: opts,
+	}
+}
+
+// Get retrieves a value from the cache by key.
+func (m *MemoryProvider) Get(ctx context.Context, key string) ([]byte, bool) {
+	// First try with read lock for fast path
+	m.mu.RLock()
+	item, exists := m.items[key]
+	if !exists {
+		m.mu.RUnlock()
+		m.misses.Add(1)
+		return nil, false
+	}
+
+	if item.isExpired() {
+		m.mu.RUnlock()
+		// Upgrade to write lock to delete expired item
+		m.mu.Lock()
+		delete(m.items, key)
+		m.mu.Unlock()
+		m.misses.Add(1)
+		return nil, false
+	}
+
+	// Update stats and access time with write lock
+	value := item.Value
+	m.mu.RUnlock()
+
+	// Update access tracking with write lock
+	m.mu.Lock()
+	item.LastAccess = time.Now()
+	item.HitCount++
+	m.mu.Unlock()
+
+	m.hits.Add(1)
+	return value, true
+}
+
+// Set stores a value in the cache with the specified TTL.
+func (m *MemoryProvider) Set(ctx context.Context, key string, value []byte, ttl time.Duration) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	if ttl == 0 {
+		ttl = m.options.DefaultTTL
+	}
+
+	var expiration time.Time
+	if ttl > 0 {
+		expiration = time.Now().Add(ttl)
+	}
+
+	// Check max size and evict if necessary
+	if m.options.MaxSize > 0 && len(m.items) >= m.options.MaxSize {
+		if _, exists := m.items[key]; !exists {
+			m.evictOne()
+		}
+	}
+
+	m.items[key] = &memoryItem{
+		Value:      value,
+		Expiration: expiration,
+		LastAccess: time.Now(),
+	}
+
+	return nil
+}
+
+// Delete removes a key from the cache.
+func (m *MemoryProvider) Delete(ctx context.Context, key string) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	delete(m.items, key)
+	return nil
+}
+
+// DeleteByPattern removes all keys matching the pattern.
+func (m *MemoryProvider) DeleteByPattern(ctx context.Context, pattern string) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	re, err := regexp.Compile(pattern)
+	if err != nil {
+		return fmt.Errorf("invalid pattern: %w", err)
+	}
+
+	for key := range m.items {
+		if re.MatchString(key) {
+			delete(m.items, key)
+		}
+	}
+
+	return nil
+}
+
+// Clear removes all items from the cache.
+func (m *MemoryProvider) Clear(ctx context.Context) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	m.items = make(map[string]*memoryItem)
+	m.hits.Store(0)
+	m.misses.Store(0)
+	return nil
+}
+
+// Exists checks if a key exists in the cache.
+func (m *MemoryProvider) Exists(ctx context.Context, key string) bool {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+
+	item, exists := m.items[key]
+	if !exists {
+		return false
+	}
+
+	return !item.isExpired()
+}
+
+// Close closes the provider and releases any resources.
+func (m *MemoryProvider) Close() error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	m.items = nil
+	return nil
+}
+
+// Stats returns statistics about the cache provider.
+func (m *MemoryProvider) Stats(ctx context.Context) (*CacheStats, error) {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+
+	// Clean expired items first
+	validKeys := 0
+	for _, item := range m.items {
+		if !item.isExpired() {
+			validKeys++
+		}
+	}
+
+	return &CacheStats{
+		Hits:         m.hits.Load(),
+		Misses:       m.misses.Load(),
+		Keys:         int64(validKeys),
+		ProviderType: "memory",
+		ProviderStats: map[string]any{
+			"capacity": m.options.MaxSize,
+		},
+	}, nil
+}
+
+// evictOne removes one item from the cache using LRU strategy.
+func (m *MemoryProvider) evictOne() {
+	var oldestKey string
+	var oldestTime time.Time
+
+	for key, item := range m.items {
+		if item.isExpired() {
+			delete(m.items, key)
+			return
+		}
+
+		if oldestKey == "" || item.LastAccess.Before(oldestTime) {
+			oldestKey = key
+			oldestTime = item.LastAccess
+		}
+	}
+
+	if oldestKey != "" {
+		delete(m.items, oldestKey)
+	}
+}
+
+// CleanExpired removes all expired items from the cache.
+func (m *MemoryProvider) CleanExpired(ctx context.Context) int {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	count := 0
+	for key, item := range m.items {
+		if item.isExpired() {
+			delete(m.items, key)
+			count++
+		}
+	}
+
+	return count
+}

pkg/cache/provider_redis.go

@@ -0,0 +1,185 @@
+package cache
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+)
+
+// RedisProvider is a Redis implementation of the Provider interface.
+type RedisProvider struct {
+	client  *redis.Client
+	options *Options
+}
+
+// RedisConfig contains Redis-specific configuration.
+type RedisConfig struct {
+	// Host is the Redis server host (default: localhost)
+	Host string
+
+	// Port is the Redis server port (default: 6379)
+	Port int
+
+	// Password for Redis authentication (optional)
+	Password string
+
+	// DB is the Redis database number (default: 0)
+	DB int
+
+	// PoolSize is the maximum number of connections (default: 10)
+	PoolSize int
+
+	// Options contains general cache options
+	Options *Options
+}
+
+// NewRedisProvider creates a new Redis cache provider.
+func NewRedisProvider(config *RedisConfig) (*RedisProvider, error) {
+	if config == nil {
+		config = &RedisConfig{
+			Host: "localhost",
+			Port: 6379,
+			DB:   0,
+		}
+	}
+
+	if config.Host == "" {
+		config.Host = "localhost"
+	}
+	if config.Port == 0 {
+		config.Port = 6379
+	}
+	if config.PoolSize == 0 {
+		config.PoolSize = 10
+	}
+
+	if config.Options == nil {
+		config.Options = &Options{
+			DefaultTTL: 5 * time.Minute,
+		}
+	}
+
+	client := redis.NewClient(&redis.Options{
+		Addr:     fmt.Sprintf("%s:%d", config.Host, config.Port),
+		Password: config.Password,
+		DB:       config.DB,
+		PoolSize: config.PoolSize,
+	})
+
+	// Test connection
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	if err := client.Ping(ctx).Err(); err != nil {
+		return nil, fmt.Errorf("failed to connect to Redis: %w", err)
+	}
+
+	return &RedisProvider{
+		client:  client,
+		options: config.Options,
+	}, nil
+}
+
+// Get retrieves a value from the cache by key.
+func (r *RedisProvider) Get(ctx context.Context, key string) ([]byte, bool) {
+	val, err := r.client.Get(ctx, key).Bytes()
+	if err == redis.Nil {
+		return nil, false
+	}
+	if err != nil {
+		return nil, false
+	}
+	return val, true
+}
+
+// Set stores a value in the cache with the specified TTL.
+func (r *RedisProvider) Set(ctx context.Context, key string, value []byte, ttl time.Duration) error {
+	if ttl == 0 {
+		ttl = r.options.DefaultTTL
+	}
+
+	return r.client.Set(ctx, key, value, ttl).Err()
+}
+
+// Delete removes a key from the cache.
+func (r *RedisProvider) Delete(ctx context.Context, key string) error {
+	return r.client.Del(ctx, key).Err()
+}
+
+// DeleteByPattern removes all keys matching the pattern.
+func (r *RedisProvider) DeleteByPattern(ctx context.Context, pattern string) error {
+	iter := r.client.Scan(ctx, 0, pattern, 0).Iterator()
+	pipe := r.client.Pipeline()
+
+	count := 0
+	for iter.Next(ctx) {
+		pipe.Del(ctx, iter.Val())
+		count++
+
+		// Execute pipeline in batches of 100
+		if count%100 == 0 {
+			if _, err := pipe.Exec(ctx); err != nil {
+				return err
+			}
+			pipe = r.client.Pipeline()
+		}
+	}
+
+	if err := iter.Err(); err != nil {
+		return err
+	}
+
+	// Execute remaining commands
+	if count%100 != 0 {
+		_, err := pipe.Exec(ctx)
+		return err
+	}
+
+	return nil
+}
+
+// Clear removes all items from the cache.
+func (r *RedisProvider) Clear(ctx context.Context) error {
+	return r.client.FlushDB(ctx).Err()
+}
+
+// Exists checks if a key exists in the cache.
+func (r *RedisProvider) Exists(ctx context.Context, key string) bool {
+	result, err := r.client.Exists(ctx, key).Result()
+	if err != nil {
+		return false
+	}
+	return result > 0
+}
+
+// Close closes the provider and releases any resources.
+func (r *RedisProvider) Close() error {
+	return r.client.Close()
+}
+
+// Stats returns statistics about the cache provider.
+func (r *RedisProvider) Stats(ctx context.Context) (*CacheStats, error) {
+	info, err := r.client.Info(ctx, "stats", "keyspace").Result()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get Redis stats: %w", err)
+	}
+
+	dbSize, err := r.client.DBSize(ctx).Result()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get DB size: %w", err)
+	}
+
+	// Parse stats from INFO command
+	// This is a simplified version - you may want to parse more detailed stats
+	stats := &CacheStats{
+		Keys:         dbSize,
+		ProviderType: "redis",
+		ProviderStats: map[string]any{
+			"info": info,
+		},
+	}
+
+	return stats, nil
+}

pkg/cache/query_cache.go

@@ -0,0 +1,127 @@
+package cache
+
+import (
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+)
+
+// QueryCacheKey represents the components used to build a cache key for query total count
+type QueryCacheKey struct {
+	TableName      string                `json:"table_name"`
+	Filters        []common.FilterOption `json:"filters"`
+	Sort           []common.SortOption   `json:"sort"`
+	CustomSQLWhere string                `json:"custom_sql_where,omitempty"`
+	CustomSQLOr    string                `json:"custom_sql_or,omitempty"`
+	Expand         []ExpandOptionKey     `json:"expand,omitempty"`
+	Distinct       bool                  `json:"distinct,omitempty"`
+	CursorForward  string                `json:"cursor_forward,omitempty"`
+	CursorBackward string                `json:"cursor_backward,omitempty"`
+}
+
+// ExpandOptionKey represents expand options for cache key
+type ExpandOptionKey struct {
+	Relation string `json:"relation"`
+	Where    string `json:"where,omitempty"`
+}
+
+// BuildQueryCacheKey builds a cache key from query parameters for total count caching
+// This is used to cache the total count of records matching a query
+func BuildQueryCacheKey(tableName string, filters []common.FilterOption, sort []common.SortOption, customWhere, customOr string) string {
+	key := QueryCacheKey{
+		TableName:      tableName,
+		Filters:        filters,
+		Sort:           sort,
+		CustomSQLWhere: customWhere,
+		CustomSQLOr:    customOr,
+	}
+
+	// Serialize to JSON for consistent hashing
+	jsonData, err := json.Marshal(key)
+	if err != nil {
+		// Fallback to simple string concatenation if JSON fails
+		return hashString(fmt.Sprintf("%s_%v_%v_%s_%s", tableName, filters, sort, customWhere, customOr))
+	}
+
+	return hashString(string(jsonData))
+}
+
+// BuildExtendedQueryCacheKey builds a cache key for extended query options (restheadspec)
+// Includes expand, distinct, and cursor pagination options
+func BuildExtendedQueryCacheKey(tableName string, filters []common.FilterOption, sort []common.SortOption,
+	customWhere, customOr string, expandOpts []interface{}, distinct bool, cursorFwd, cursorBwd string) string {
+
+	key := QueryCacheKey{
+		TableName:      tableName,
+		Filters:        filters,
+		Sort:           sort,
+		CustomSQLWhere: customWhere,
+		CustomSQLOr:    customOr,
+		Distinct:       distinct,
+		CursorForward:  cursorFwd,
+		CursorBackward: cursorBwd,
+	}
+
+	// Convert expand options to cache key format
+	if len(expandOpts) > 0 {
+		key.Expand = make([]ExpandOptionKey, 0, len(expandOpts))
+		for _, exp := range expandOpts {
+			// Type assert to get the expand option fields we care about for caching
+			if expMap, ok := exp.(map[string]interface{}); ok {
+				expKey := ExpandOptionKey{}
+				if rel, ok := expMap["relation"].(string); ok {
+					expKey.Relation = rel
+				}
+				if where, ok := expMap["where"].(string); ok {
+					expKey.Where = where
+				}
+				key.Expand = append(key.Expand, expKey)
+			}
+		}
+		// Sort expand options for consistent hashing (already sorted by relation name above)
+	}
+
+	// Serialize to JSON for consistent hashing
+	jsonData, err := json.Marshal(key)
+	if err != nil {
+		// Fallback to simple string concatenation if JSON fails
+		return hashString(fmt.Sprintf("%s_%v_%v_%s_%s_%v_%v_%s_%s",
+			tableName, filters, sort, customWhere, customOr, expandOpts, distinct, cursorFwd, cursorBwd))
+	}
+
+	return hashString(string(jsonData))
+}
+
+// hashString computes SHA256 hash of a string
+func hashString(s string) string {
+	h := sha256.New()
+	h.Write([]byte(s))
+	return hex.EncodeToString(h.Sum(nil))
+}
+
+// GetQueryTotalCacheKey returns a formatted cache key for storing/retrieving total count
+func GetQueryTotalCacheKey(hash string) string {
+	return fmt.Sprintf("query_total:%s", hash)
+}
+
+// CachedTotal represents a cached total count
+type CachedTotal struct {
+	Total int `json:"total"`
+}
+
+// InvalidateCacheForTable removes all cached totals for a specific table
+// This should be called when data in the table changes (insert/update/delete)
+func InvalidateCacheForTable(ctx context.Context, tableName string) error {
+	cache := GetDefaultCache()
+
+	// Build a pattern to match all query totals for this table
+	// Note: This requires pattern matching support in the provider
+	pattern := fmt.Sprintf("query_total:*%s*", strings.ToLower(tableName))
+
+	return cache.DeleteByPattern(ctx, pattern)
+}

pkg/cache/query_cache_test.go

@@ -0,0 +1,151 @@
+package cache
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+)
+
+func TestBuildQueryCacheKey(t *testing.T) {
+	filters := []common.FilterOption{
+		{Column: "name", Operator: "eq", Value: "test"},
+		{Column: "age", Operator: "gt", Value: 25},
+	}
+	sorts := []common.SortOption{
+		{Column: "name", Direction: "asc"},
+	}
+
+	// Generate cache key
+	key1 := BuildQueryCacheKey("users", filters, sorts, "status = 'active'", "")
+
+	// Same parameters should generate same key
+	key2 := BuildQueryCacheKey("users", filters, sorts, "status = 'active'", "")
+
+	if key1 != key2 {
+		t.Errorf("Expected same cache keys for identical parameters, got %s and %s", key1, key2)
+	}
+
+	// Different parameters should generate different key
+	key3 := BuildQueryCacheKey("users", filters, sorts, "status = 'inactive'", "")
+
+	if key1 == key3 {
+		t.Errorf("Expected different cache keys for different parameters, got %s and %s", key1, key3)
+	}
+}
+
+func TestBuildExtendedQueryCacheKey(t *testing.T) {
+	filters := []common.FilterOption{
+		{Column: "name", Operator: "eq", Value: "test"},
+	}
+	sorts := []common.SortOption{
+		{Column: "name", Direction: "asc"},
+	}
+	expandOpts := []interface{}{
+		map[string]interface{}{
+			"relation": "posts",
+			"where":    "status = 'published'",
+		},
+	}
+
+	// Generate cache key
+	key1 := BuildExtendedQueryCacheKey("users", filters, sorts, "", "", expandOpts, false, "", "")
+
+	// Same parameters should generate same key
+	key2 := BuildExtendedQueryCacheKey("users", filters, sorts, "", "", expandOpts, false, "", "")
+
+	if key1 != key2 {
+		t.Errorf("Expected same cache keys for identical parameters")
+	}
+
+	// Different distinct value should generate different key
+	key3 := BuildExtendedQueryCacheKey("users", filters, sorts, "", "", expandOpts, true, "", "")
+
+	if key1 == key3 {
+		t.Errorf("Expected different cache keys for different distinct values")
+	}
+}
+
+func TestGetQueryTotalCacheKey(t *testing.T) {
+	hash := "abc123"
+	key := GetQueryTotalCacheKey(hash)
+
+	expected := "query_total:abc123"
+	if key != expected {
+		t.Errorf("Expected %s, got %s", expected, key)
+	}
+}
+
+func TestCachedTotalIntegration(t *testing.T) {
+	// Initialize cache with memory provider for testing
+	UseMemory(&Options{
+		DefaultTTL: 1 * time.Minute,
+		MaxSize:    100,
+	})
+
+	ctx := context.Background()
+
+	// Create test data
+	filters := []common.FilterOption{
+		{Column: "status", Operator: "eq", Value: "active"},
+	}
+	sorts := []common.SortOption{
+		{Column: "created_at", Direction: "desc"},
+	}
+
+	// Build cache key
+	cacheKeyHash := BuildQueryCacheKey("test_table", filters, sorts, "", "")
+	cacheKey := GetQueryTotalCacheKey(cacheKeyHash)
+
+	// Store a total count in cache
+	totalToCache := CachedTotal{Total: 42}
+	err := GetDefaultCache().Set(ctx, cacheKey, totalToCache, time.Minute)
+	if err != nil {
+		t.Fatalf("Failed to set cache: %v", err)
+	}
+
+	// Retrieve from cache
+	var cachedTotal CachedTotal
+	err = GetDefaultCache().Get(ctx, cacheKey, &cachedTotal)
+	if err != nil {
+		t.Fatalf("Failed to get from cache: %v", err)
+	}
+
+	if cachedTotal.Total != 42 {
+		t.Errorf("Expected total 42, got %d", cachedTotal.Total)
+	}
+
+	// Test cache miss
+	nonExistentKey := GetQueryTotalCacheKey("nonexistent")
+	var missedTotal CachedTotal
+	err = GetDefaultCache().Get(ctx, nonExistentKey, &missedTotal)
+	if err == nil {
+		t.Errorf("Expected error for cache miss, got nil")
+	}
+}
+
+func TestHashString(t *testing.T) {
+	input1 := "test string"
+	input2 := "test string"
+	input3 := "different string"
+
+	hash1 := hashString(input1)
+	hash2 := hashString(input2)
+	hash3 := hashString(input3)
+
+	// Same input should produce same hash
+	if hash1 != hash2 {
+		t.Errorf("Expected same hash for identical inputs")
+	}
+
+	// Different input should produce different hash
+	if hash1 == hash3 {
+		t.Errorf("Expected different hash for different inputs")
+	}
+
+	// Hash should be hex encoded SHA256 (64 characters)
+	if len(hash1) != 64 {
+		t.Errorf("Expected hash length of 64, got %d", len(hash1))
+	}
+}

pkg/common/adapters/database/RELATION_LOADING.md

@@ -0,0 +1,218 @@
+# Automatic Relation Loading Strategies
+
+## Overview
+
+**NEW:** The database adapters now **automatically** choose the optimal loading strategy by inspecting your model's relationship tags!
+
+Simply use `PreloadRelation()` and the system automatically:
+- Detects relationship type from Bun/GORM tags
+- Uses **JOIN** for many-to-one and one-to-one (efficient, no duplication)
+- Uses **separate query** for one-to-many and many-to-many (avoids duplication)
+
+## How It Works
+
+```go
+// Just write this - the system handles the rest!
+db.NewSelect().
+    Model(&links).
+    PreloadRelation("Provider").  // ✓ Auto-detects belongs-to → uses JOIN
+    PreloadRelation("Tags").      // ✓ Auto-detects has-many → uses separate query
+    Scan(ctx, &links)
+```
+
+### Detection Logic
+
+The system inspects your model's struct tags:
+
+**Bun models:**
+```go
+type Link struct {
+    Provider   *Provider `bun:"rel:belongs-to"`   // → Detected: belongs-to → JOIN
+    Tags       []Tag     `bun:"rel:has-many"`     // → Detected: has-many → Separate query
+}
+```
+
+**GORM models:**
+```go
+type Link struct {
+    ProviderID int
+    Provider   *Provider `gorm:"foreignKey:ProviderID"`  // → Detected: belongs-to → JOIN
+    Tags       []Tag     `gorm:"many2many:link_tags"`    // → Detected: many-to-many → Separate query
+}
+```
+
+**Type inference (fallback):**
+- `[]Type` (slice) → has-many → Separate query
+- `*Type` (pointer) → belongs-to → JOIN
+- `Type` (struct) → belongs-to → JOIN
+
+### What Gets Logged
+
+Enable debug logging to see strategy selection:
+
+```go
+bunAdapter.EnableQueryDebug()
+```
+
+**Output:**
+```
+DEBUG: PreloadRelation 'Provider' detected as: belongs-to
+INFO:  Using JOIN strategy for belongs-to relation 'Provider'
+DEBUG: PreloadRelation 'Links' detected as: has-many
+DEBUG: Using separate query for has-many relation 'Links'
+```
+
+## Relationship Types
+
+| Bun Tag | GORM Pattern | Field Type | Strategy | Why |
+|---------|--------------|------------|----------|-----|
+| `rel:has-many` | Slice field | `[]Type` | Separate Query | Avoids duplicating parent data |
+| `rel:belongs-to` | `foreignKey:` | `*Type` | JOIN | Single parent, no duplication |
+| `rel:has-one` | Single pointer | `*Type` | JOIN | One-to-one, no duplication |
+| `rel:many-to-many` | `many2many:` | `[]Type` | Separate Query | Complex join, avoid cartesian |
+
+## Manual Override
+
+If you need to force a specific strategy, use `JoinRelation()`:
+
+```go
+// Force JOIN even for has-many (not recommended)
+db.NewSelect().
+    Model(&providers).
+    JoinRelation("Links").  // Explicitly use JOIN
+    Scan(ctx, &providers)
+```
+
+## Examples
+
+### Automatic Strategy Selection (Recommended)
+
+```go
+// Example 1: Loading parent provider for each link
+// System detects belongs-to → uses JOIN automatically
+db.NewSelect().
+    Model(&links).
+    PreloadRelation("Provider", func(q common.SelectQuery) common.SelectQuery {
+        return q.Where("active = ?", true)
+    }).
+    Scan(ctx, &links)
+
+// Generated SQL: Single query with JOIN
+// SELECT links.*, providers.*
+// FROM links
+// LEFT JOIN providers ON links.provider_id = providers.id
+// WHERE providers.active = true
+
+// Example 2: Loading child links for each provider
+// System detects has-many → uses separate query automatically
+db.NewSelect().
+    Model(&providers).
+    PreloadRelation("Links", func(q common.SelectQuery) common.SelectQuery {
+        return q.Where("active = ?", true)
+    }).
+    Scan(ctx, &providers)
+
+// Generated SQL: Two queries
+// Query 1: SELECT * FROM providers
+// Query 2: SELECT * FROM links
+//          WHERE provider_id IN (1, 2, 3, ...)
+//          AND active = true
+```
+
+### Mixed Relationships
+
+```go
+type Order struct {
+    ID         int
+    CustomerID int
+    Customer   *Customer `bun:"rel:belongs-to"`    // JOIN
+    Items      []Item    `bun:"rel:has-many"`      // Separate
+    Invoice    *Invoice  `bun:"rel:has-one"`       // JOIN
+}
+
+// All three handled optimally!
+db.NewSelect().
+    Model(&orders).
+    PreloadRelation("Customer").  // → JOIN (many-to-one)
+    PreloadRelation("Items").     // → Separate (one-to-many)
+    PreloadRelation("Invoice").   // → JOIN (one-to-one)
+    Scan(ctx, &orders)
+```
+
+## Performance Benefits
+
+### Before (Manual Strategy Selection)
+
+```go
+// You had to remember which to use:
+.PreloadRelation("Provider")  // Should I use PreloadRelation or JoinRelation?
+.PreloadRelation("Links")     // Which is more efficient here?
+```
+
+### After (Automatic Selection)
+
+```go
+// Just use PreloadRelation everywhere:
+.PreloadRelation("Provider")  // ✓ System uses JOIN automatically
+.PreloadRelation("Links")     // ✓ System uses separate query automatically
+```
+
+## Migration Guide
+
+**No changes needed!** If you're already using `PreloadRelation()`, it now automatically optimizes:
+
+```go
+// Before: Always used separate query
+.PreloadRelation("Provider")  // Inefficient: extra round trip
+
+// After: Automatic optimization
+.PreloadRelation("Provider")  // ✓ Now uses JOIN automatically!
+```
+
+## Implementation Details
+
+### Supported Bun Tags
+- `rel:has-many` → Separate query
+- `rel:belongs-to` → JOIN
+- `rel:has-one` → JOIN
+- `rel:many-to-many` or `rel:m2m` → Separate query
+
+### Supported GORM Patterns
+- `many2many:` tag → Separate query
+- `foreignKey:` tag → JOIN (belongs-to)
+- `[]Type` slice without many2many → Separate query (has-many)
+- `*Type` pointer with foreignKey → JOIN (belongs-to)
+- `*Type` pointer without foreignKey → JOIN (has-one)
+
+### Fallback Behavior
+- `[]Type` (slice) → Separate query (safe default for collections)
+- `*Type` or `Type` (single) → JOIN (safe default for single relations)
+- Unknown → Separate query (safest default)
+
+## Debugging
+
+To see strategy selection in action:
+
+```go
+// Enable debug logging
+bunAdapter.EnableQueryDebug()  // or gormAdapter.EnableQueryDebug()
+
+// Run your query
+db.NewSelect().
+    Model(&records).
+    PreloadRelation("RelationName").
+    Scan(ctx, &records)
+
+// Check logs for:
+// - "PreloadRelation 'X' detected as: belongs-to"
+// - "Using JOIN strategy for belongs-to relation 'X'"
+// - Actual SQL queries executed
+```
+
+## Best Practices
+
+1. **Use PreloadRelation() for everything** - Let the system optimize
+2. **Define proper relationship tags** - Ensures correct detection
+3. **Only use JoinRelation() for overrides** - When you know better than auto-detection
+4. **Enable debug logging during development** - Verify optimal strategies are chosen
+5. **Trust the system** - It's designed to choose correctly based on relationship type

pkg/common/adapters/database/alias_test.go

@@ -0,0 +1,81 @@
+package database
+
+import (
+	"testing"
+)
+
+func TestNormalizeTableAlias(t *testing.T) {
+	tests := []struct {
+		name          string
+		query         string
+		expectedAlias string
+		tableName     string
+		want          string
+	}{
+		{
+			name:          "strips plausible alias from simple condition",
+			query:         "APIL.rid_hub = 2576",
+			expectedAlias: "apiproviderlink",
+			tableName:     "apiproviderlink",
+			want:          "rid_hub = 2576",
+		},
+		{
+			name:          "keeps correct alias",
+			query:         "apiproviderlink.rid_hub = 2576",
+			expectedAlias: "apiproviderlink",
+			tableName:     "apiproviderlink",
+			want:          "apiproviderlink.rid_hub = 2576",
+		},
+		{
+			name:          "strips plausible alias with multiple conditions",
+			query:         "APIL.rid_hub = ? AND APIL.active = ?",
+			expectedAlias: "apiproviderlink",
+			tableName:     "apiproviderlink",
+			want:          "rid_hub = ? AND active = ?",
+		},
+		{
+			name:          "handles mixed correct and plausible aliases",
+			query:         "APIL.rid_hub = ? AND apiproviderlink.active = ?",
+			expectedAlias: "apiproviderlink",
+			tableName:     "apiproviderlink",
+			want:          "rid_hub = ? AND apiproviderlink.active = ?",
+		},
+		{
+			name:          "handles parentheses",
+			query:         "(APIL.rid_hub = ?)",
+			expectedAlias: "apiproviderlink",
+			tableName:     "apiproviderlink",
+			want:          "(rid_hub = ?)",
+		},
+		{
+			name:          "no alias in query",
+			query:         "rid_hub = ?",
+			expectedAlias: "apiproviderlink",
+			tableName:     "apiproviderlink",
+			want:          "rid_hub = ?",
+		},
+		{
+			name:          "keeps reference to different table (not in current table name)",
+			query:         "APIL.rid_hub = ?",
+			expectedAlias: "apiprovider",
+			tableName:     "apiprovider",
+			want:          "APIL.rid_hub = ?",
+		},
+		{
+			name:          "keeps reference with short prefix that might be ambiguous",
+			query:         "AP.rid = ?",
+			expectedAlias: "apiprovider",
+			tableName:     "apiprovider",
+			want:          "AP.rid = ?",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := normalizeTableAlias(tt.query, tt.expectedAlias, tt.tableName)
+			if got != tt.want {
+				t.Errorf("normalizeTableAlias() = %q, want %q", got, tt.want)
+			}
+		})
+	}
+}

pkg/common/adapters/database/bun.go

@@ -4,15 +4,36 @@ import (
 	"context"
 	"database/sql"
 	"fmt"
+	"reflect"
 	"strings"
+	"time"
 
 	"github.com/uptrace/bun"
 
 	"github.com/bitechdev/ResolveSpec/pkg/common"
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
 	"github.com/bitechdev/ResolveSpec/pkg/modelregistry"
 	"github.com/bitechdev/ResolveSpec/pkg/reflection"
 )
 
+// QueryDebugHook is a Bun query hook that logs all SQL queries including preloads
+type QueryDebugHook struct{}
+
+func (h *QueryDebugHook) BeforeQuery(ctx context.Context, event *bun.QueryEvent) context.Context {
+	return ctx
+}
+
+func (h *QueryDebugHook) AfterQuery(ctx context.Context, event *bun.QueryEvent) {
+	query := event.Query
+	duration := time.Since(event.StartTime)
+
+	if event.Err != nil {
+		logger.Error("SQL Query Failed [%s]: %s. Error: %v", duration, query, event.Err)
+	} else {
+		logger.Debug("SQL Query Success [%s]: %s", duration, query)
+	}
+}
+
 // BunAdapter adapts Bun to work with our Database interface
 // This demonstrates how the abstraction works with different ORMs
 type BunAdapter struct {
@@ -24,6 +45,20 @@ func NewBunAdapter(db *bun.DB) *BunAdapter {
 	return &BunAdapter{db: db}
 }
 
+// EnableQueryDebug enables query debugging which logs all SQL queries including preloads
+// This is useful for debugging preload queries that may be failing
+func (b *BunAdapter) EnableQueryDebug() {
+	b.db.AddQueryHook(&QueryDebugHook{})
+	logger.Info("Bun query debug mode enabled - all SQL queries will be logged")
+}
+
+// DisableQueryDebug removes all query hooks
+func (b *BunAdapter) DisableQueryDebug() {
+	// Create a new DB without hooks
+	// Note: Bun doesn't have a RemoveQueryHook, so we'd need to track hooks manually
+	logger.Info("To disable query debug, recreate the BunAdapter without adding the hook")
+}
+
 func (b *BunAdapter) NewSelect() common.SelectQuery {
 	return &BunSelectQuery{
 		query: b.db.NewSelect(),
@@ -43,12 +78,22 @@ func (b *BunAdapter) NewDelete() common.DeleteQuery {
 	return &BunDeleteQuery{query: b.db.NewDelete()}
 }
 
-func (b *BunAdapter) Exec(ctx context.Context, query string, args ...interface{}) (common.Result, error) {
+func (b *BunAdapter) Exec(ctx context.Context, query string, args ...interface{}) (res common.Result, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("BunAdapter.Exec", r)
+		}
+	}()
 	result, err := b.db.ExecContext(ctx, query, args...)
 	return &BunResult{result: result}, err
 }
 
-func (b *BunAdapter) Query(ctx context.Context, dest interface{}, query string, args ...interface{}) error {
+func (b *BunAdapter) Query(ctx context.Context, dest interface{}, query string, args ...interface{}) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("BunAdapter.Query", r)
+		}
+	}()
 	return b.db.NewRaw(query, args...).Scan(ctx, dest)
 }
 
@@ -73,7 +118,12 @@ func (b *BunAdapter) RollbackTx(ctx context.Context) error {
 	return nil
 }
 
-func (b *BunAdapter) RunInTransaction(ctx context.Context, fn func(common.Database) error) error {
+func (b *BunAdapter) RunInTransaction(ctx context.Context, fn func(common.Database) error) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("BunAdapter.RunInTransaction", r)
+		}
+	}()
 	return b.db.RunInTx(ctx, &sql.TxOptions{}, func(ctx context.Context, tx bun.Tx) error {
 		// Create adapter with transaction
 		adapter := &BunTxAdapter{tx: tx}
@@ -83,12 +133,22 @@ func (b *BunAdapter) RunInTransaction(ctx context.Context, fn func(common.Databa
 
 // BunSelectQuery implements SelectQuery for Bun
 type BunSelectQuery struct {
-	query      *bun.SelectQuery
-	db         bun.IDB // Store DB connection for count queries
-	hasModel   bool    // Track if Model() was called
-	schema     string  // Separated schema name
-	tableName  string  // Just the table name, without schema
-	tableAlias string
+	query            *bun.SelectQuery
+	db               bun.IDB // Store DB connection for count queries
+	hasModel         bool    // Track if Model() was called
+	schema           string  // Separated schema name
+	tableName        string  // Just the table name, without schema
+	tableAlias       string
+	deferredPreloads []deferredPreload // Preloads to execute as separate queries
+	inJoinContext    bool              // Track if we're in a JOIN relation context
+	joinTableAlias   string            // Alias to use for JOIN conditions
+}
+
+// deferredPreload represents a preload that will be executed as a separate query
+// to avoid PostgreSQL identifier length limits
+type deferredPreload struct {
+	relation string
+	apply    []func(common.SelectQuery) common.SelectQuery
 }
 
 func (b *BunSelectQuery) Model(model interface{}) common.SelectQuery {
@@ -122,16 +182,156 @@ func (b *BunSelectQuery) Column(columns ...string) common.SelectQuery {
 }
 
 func (b *BunSelectQuery) ColumnExpr(query string, args ...interface{}) common.SelectQuery {
-	b.query = b.query.ColumnExpr(query, args)
-
+	if len(args) > 0 {
+		b.query = b.query.ColumnExpr(query, args)
+	} else {
+		b.query = b.query.ColumnExpr(query)
+	}
 	return b
 }
 
 func (b *BunSelectQuery) Where(query string, args ...interface{}) common.SelectQuery {
+	// If we're in a JOIN context, add table prefix to unqualified columns
+	if b.inJoinContext && b.joinTableAlias != "" {
+		query = addTablePrefix(query, b.joinTableAlias)
+	} else if b.tableAlias != "" && b.tableName != "" {
+		// If we have a table alias defined, check if the query references a different alias
+		// This can happen in preloads where the user expects a certain alias but Bun generates another
+		query = normalizeTableAlias(query, b.tableAlias, b.tableName)
+	}
 	b.query = b.query.Where(query, args...)
 	return b
 }
 
+// addTablePrefix adds a table prefix to unqualified column references
+// This is used in JOIN contexts where conditions must reference the joined table
+func addTablePrefix(query, tableAlias string) string {
+	if tableAlias == "" || query == "" {
+		return query
+	}
+
+	// Split on spaces and parentheses to find column references
+	parts := strings.FieldsFunc(query, func(r rune) bool {
+		return r == ' ' || r == '(' || r == ')' || r == ','
+	})
+
+	modified := query
+	for _, part := range parts {
+		// Check if this looks like an unqualified column reference
+		// (no dot, and likely a column name before an operator)
+		if !strings.Contains(part, ".") {
+			// Extract potential column name (before = or other operators)
+			for _, op := range []string{"=", "!=", "<>", ">", ">=", "<", "<=", " LIKE ", " IN ", " IS "} {
+				if strings.Contains(part, op) {
+					colName := strings.Split(part, op)[0]
+					colName = strings.TrimSpace(colName)
+					if colName != "" && !isOperatorOrKeyword(colName) {
+						// Add table prefix
+						prefixed := tableAlias + "." + colName + strings.TrimPrefix(part, colName)
+						modified = strings.ReplaceAll(modified, part, prefixed)
+						logger.Debug("Adding table prefix '%s' to column '%s' in JOIN condition", tableAlias, colName)
+					}
+					break
+				}
+			}
+		}
+	}
+
+	return modified
+}
+
+// isOperatorOrKeyword checks if a string is likely an operator or SQL keyword
+func isOperatorOrKeyword(s string) bool {
+	s = strings.ToUpper(strings.TrimSpace(s))
+	keywords := []string{"AND", "OR", "NOT", "IN", "IS", "NULL", "TRUE", "FALSE", "LIKE", "BETWEEN"}
+	for _, kw := range keywords {
+		if s == kw {
+			return true
+		}
+	}
+	return false
+}
+
+// isAcronymMatch checks if prefix is an acronym of tableName
+// For example, "apil" matches "apiproviderlink" because each letter appears in sequence
+func isAcronymMatch(prefix, tableName string) bool {
+	if len(prefix) == 0 || len(tableName) == 0 {
+		return false
+	}
+
+	prefixIdx := 0
+	for i := 0; i < len(tableName) && prefixIdx < len(prefix); i++ {
+		if tableName[i] == prefix[prefixIdx] {
+			prefixIdx++
+		}
+	}
+
+	// All characters of prefix were found in sequence in tableName
+	return prefixIdx == len(prefix)
+}
+
+// normalizeTableAlias replaces table alias prefixes in SQL conditions
+// This handles cases where a user references a table alias that doesn't match
+// what Bun generates (common in preload contexts)
+func normalizeTableAlias(query, expectedAlias, tableName string) string {
+	// Pattern: <word>.<column> where <word> might be an incorrect alias
+	// We'll look for patterns like "APIL.column" and either:
+	// 1. Remove the alias prefix if it's clearly meant for this table
+	// 2. Leave it alone if it might be referring to another table (JOIN/preload)
+
+	// Split on spaces and parentheses to find qualified references
+	parts := strings.FieldsFunc(query, func(r rune) bool {
+		return r == ' ' || r == '(' || r == ')' || r == ','
+	})
+
+	modified := query
+	for _, part := range parts {
+		// Check if this looks like a qualified column reference
+		if dotIndex := strings.Index(part, "."); dotIndex > 0 {
+			prefix := part[:dotIndex]
+			column := part[dotIndex+1:]
+
+			// Check if the prefix matches our expected alias or table name (case-insensitive)
+			if strings.EqualFold(prefix, expectedAlias) ||
+				strings.EqualFold(prefix, tableName) ||
+				strings.EqualFold(prefix, strings.ToLower(tableName)) {
+				// Prefix matches current table, it's safe but redundant - leave it
+				continue
+			}
+
+			// Check if the prefix could plausibly be an alias/acronym for this table
+			// Only strip if we're confident it's meant for this table
+			// For example: "APIL" could be an acronym for "apiproviderlink"
+			prefixLower := strings.ToLower(prefix)
+			tableNameLower := strings.ToLower(tableName)
+
+			// Check if prefix is a substring of table name
+			isSubstring := strings.Contains(tableNameLower, prefixLower) && len(prefixLower) > 2
+
+			// Check if prefix is an acronym of table name
+			// e.g., "APIL" matches "ApiProviderLink" (A-p-I-providerL-ink)
+			isAcronym := false
+			if !isSubstring && len(prefixLower) > 2 {
+				isAcronym = isAcronymMatch(prefixLower, tableNameLower)
+			}
+
+			if isSubstring || isAcronym {
+				// This looks like it could be an alias for this table - strip it
+				logger.Debug("Stripping plausible alias '%s' from WHERE condition, keeping just '%s'", prefix, column)
+				// Replace the qualified reference with just the column name
+				modified = strings.ReplaceAll(modified, part, column)
+			} else {
+				// Prefix doesn't match the current table at all
+				// It's likely referring to a different table (JOIN/preload)
+				// DON'T strip it - leave the qualified reference as-is
+				logger.Debug("Keeping qualified reference '%s' - prefix '%s' doesn't match current table '%s'", part, prefix, tableName)
+			}
+		}
+	}
+
+	return modified
+}
+
 func (b *BunSelectQuery) WhereOr(query string, args ...interface{}) common.SelectQuery {
 	b.query = b.query.WhereOr(query, args...)
 	return b
@@ -217,8 +417,122 @@ func (b *BunSelectQuery) Preload(relation string, conditions ...interface{}) com
 	return b
 }
 
+// // shortenAliasForPostgres shortens a table/relation alias if it would exceed PostgreSQL's 63-char limit
+// // when combined with typical column names
+// func shortenAliasForPostgres(relationPath string) (string, bool) {
+// 	// Convert relation path to the alias format Bun uses: dots become double underscores
+// 	// Also convert to lowercase and use snake_case as Bun does
+// 	parts := strings.Split(relationPath, ".")
+// 	alias := strings.ToLower(strings.Join(parts, "__"))
+
+// 	// PostgreSQL truncates identifiers to 63 chars
+// 	// If the alias + typical column name would exceed this, we need to shorten
+// 	// Reserve at least 30 chars for column names (e.g., "__rid_mastertype_hubtype")
+// 	const maxAliasLength = 30
+
+// 	if len(alias) > maxAliasLength {
+// 		// Create a shortened alias using a hash of the original
+// 		hash := md5.Sum([]byte(alias))
+// 		hashStr := hex.EncodeToString(hash[:])[:8]
+
+// 		// Keep first few chars of original for readability + hash
+// 		prefixLen := maxAliasLength - 9 // 9 = 1 underscore + 8 hash chars
+// 		if prefixLen > len(alias) {
+// 			prefixLen = len(alias)
+// 		}
+
+// 		shortened := alias[:prefixLen] + "_" + hashStr
+// 		logger.Debug("Shortened alias '%s' (%d chars) to '%s' (%d chars) to avoid PostgreSQL 63-char limit",
+// 			alias, len(alias), shortened, len(shortened))
+// 		return shortened, true
+// 	}
+
+// 	return alias, false
+// }
+
+// // estimateColumnAliasLength estimates the length of a column alias in a nested preload
+// // Bun creates aliases like: relationChain__columnName
+// func estimateColumnAliasLength(relationPath string, columnName string) int {
+// 	relationParts := strings.Split(relationPath, ".")
+// 	aliasChain := strings.ToLower(strings.Join(relationParts, "__"))
+// 	// Bun adds "__" between alias and column name
+// 	return len(aliasChain) + 2 + len(columnName)
+// }
+
 func (b *BunSelectQuery) PreloadRelation(relation string, apply ...func(common.SelectQuery) common.SelectQuery) common.SelectQuery {
+	// Auto-detect relationship type and choose optimal loading strategy
+	// Get the model from the query if available
+	model := b.query.GetModel()
+	if model != nil && model.Value() != nil {
+		relType := reflection.GetRelationType(model.Value(), relation)
+
+		// Log the detected relationship type
+		logger.Debug("PreloadRelation '%s' detected as: %s", relation, relType)
+
+		// If this is a belongs-to or has-one relation, use JOIN for better performance
+		if relType.ShouldUseJoin() {
+			logger.Info("Using JOIN strategy for %s relation '%s'", relType, relation)
+			return b.JoinRelation(relation, apply...)
+		}
+
+		// For has-many, many-to-many, or unknown: use separate query (safer default)
+		if relType == reflection.RelationHasMany || relType == reflection.RelationManyToMany {
+			logger.Debug("Using separate query for %s relation '%s'", relType, relation)
+		}
+	}
+
+	// Check if this relation chain would create problematic long aliases
+	relationParts := strings.Split(relation, ".")
+	aliasChain := strings.ToLower(strings.Join(relationParts, "__"))
+
+	// PostgreSQL's identifier limit is 63 characters
+	const postgresIdentifierLimit = 63
+	const safeAliasLimit = 35 // Leave room for column names
+
+	// If the alias chain is too long, defer this preload to be executed as a separate query
+	if len(aliasChain) > safeAliasLimit {
+		logger.Info("Preload relation '%s' creates long alias chain '%s' (%d chars). "+
+			"Using separate query to avoid PostgreSQL %d-char identifier limit.",
+			relation, aliasChain, len(aliasChain), postgresIdentifierLimit)
+
+		// For nested preloads (e.g., "Parent.Child"), split into separate preloads
+		// This avoids the long concatenated alias
+		if len(relationParts) > 1 {
+			// Load first level normally: "Parent"
+			firstLevel := relationParts[0]
+			remainingPath := strings.Join(relationParts[1:], ".")
+
+			logger.Info("Splitting nested preload: loading '%s' first, then '%s' separately",
+				firstLevel, remainingPath)
+
+			// Apply the first level preload normally
+			b.query = b.query.Relation(firstLevel)
+
+			// Store the remaining nested preload to be executed after the main query
+			b.deferredPreloads = append(b.deferredPreloads, deferredPreload{
+				relation: relation,
+				apply:    apply,
+			})
+
+			return b
+		}
+
+		// Single level but still too long - just warn and continue
+		logger.Warn("Single-level preload '%s' has a very long name (%d chars). "+
+			"Consider renaming the field to avoid potential issues.",
+			relation, len(aliasChain))
+	}
+
+	// Normal preload handling
 	b.query = b.query.Relation(relation, func(sq *bun.SelectQuery) *bun.SelectQuery {
+		defer func() {
+			if r := recover(); r != nil {
+				err := logger.HandlePanic("BunSelectQuery.PreloadRelation", r)
+				if err != nil {
+					return
+				}
+			}
+		}()
 		if len(apply) == 0 {
 			return sq
 		}
@@ -229,6 +543,28 @@ func (b *BunSelectQuery) PreloadRelation(relation string, apply ...func(common.S
 			db:    b.db,
 		}
 
+		// Try to extract table name and alias from the preload model
+		if model := sq.GetModel(); model != nil && model.Value() != nil {
+			modelValue := model.Value()
+
+			// Extract table name if model implements TableNameProvider
+			if provider, ok := modelValue.(common.TableNameProvider); ok {
+				fullTableName := provider.TableName()
+				wrapper.schema, wrapper.tableName = parseTableName(fullTableName)
+			}
+
+			// Extract table alias if model implements TableAliasProvider
+			if provider, ok := modelValue.(common.TableAliasProvider); ok {
+				wrapper.tableAlias = provider.TableAlias()
+				// Apply the alias to the Bun query so conditions can reference it
+				if wrapper.tableAlias != "" {
+					// Note: Bun's Relation() already sets up the table, but we can add
+					// the alias explicitly if needed
+					logger.Debug("Preload relation '%s' using table alias: %s", relation, wrapper.tableAlias)
+				}
+			}
+		}
+
 		// Start with the interface value (not pointer)
 		current := common.SelectQuery(wrapper)
 
@@ -251,6 +587,36 @@ func (b *BunSelectQuery) PreloadRelation(relation string, apply ...func(common.S
 	return b
 }
 
+func (b *BunSelectQuery) JoinRelation(relation string, apply ...func(common.SelectQuery) common.SelectQuery) common.SelectQuery {
+	// JoinRelation uses a LEFT JOIN instead of a separate query
+	// This is more efficient for many-to-one or one-to-one relationships
+
+	logger.Debug("JoinRelation '%s' - Using JOIN strategy with automatic WHERE prefix addition", relation)
+
+	// Wrap the apply functions to automatically add table prefix to WHERE conditions
+	wrappedApply := make([]func(common.SelectQuery) common.SelectQuery, 0, len(apply))
+	for _, fn := range apply {
+		if fn != nil {
+			wrappedFn := func(originalFn func(common.SelectQuery) common.SelectQuery) func(common.SelectQuery) common.SelectQuery {
+				return func(q common.SelectQuery) common.SelectQuery {
+					// Create a special wrapper that adds prefixes to WHERE conditions
+					if bunQuery, ok := q.(*BunSelectQuery); ok {
+						// Mark this query as being in JOIN context
+						bunQuery.inJoinContext = true
+						bunQuery.joinTableAlias = strings.ToLower(relation)
+					}
+					return originalFn(q)
+				}
+			}(fn)
+			wrappedApply = append(wrappedApply, wrappedFn)
+		}
+	}
+
+	// Use PreloadRelation with the wrapped functions
+	// Bun's Relation() will use JOIN for belongs-to and has-one relations
+	return b.PreloadRelation(relation, wrappedApply...)
+}
+
 func (b *BunSelectQuery) Order(order string) common.SelectQuery {
 	b.query = b.query.Order(order)
 	return b
@@ -276,33 +642,224 @@ func (b *BunSelectQuery) Having(having string, args ...interface{}) common.Selec
 	return b
 }
 
-func (b *BunSelectQuery) Scan(ctx context.Context, dest interface{}) error {
-	return b.query.Scan(ctx, dest)
+func (b *BunSelectQuery) Scan(ctx context.Context, dest interface{}) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("BunSelectQuery.Scan", r)
+		}
+	}()
+	if dest == nil {
+		return fmt.Errorf("destination cannot be nil")
+	}
+
+	// Execute the main query first
+	err = b.query.Scan(ctx, dest)
+	if err != nil {
+		// Log SQL string for debugging
+		sqlStr := b.query.String()
+		logger.Error("BunSelectQuery.Scan failed. SQL: %s. Error: %v", sqlStr, err)
+		return err
+	}
+
+	// Execute any deferred preloads
+	if len(b.deferredPreloads) > 0 {
+		err = b.executeDeferredPreloads(ctx, dest)
+		if err != nil {
+			logger.Warn("Failed to execute deferred preloads: %v", err)
+			// Don't fail the whole query, just log the warning
+		}
+	}
+
+	return nil
 }
 
-func (b *BunSelectQuery) ScanModel(ctx context.Context) error {
-	return b.query.Scan(ctx)
+func (b *BunSelectQuery) ScanModel(ctx context.Context) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("BunSelectQuery.ScanModel", r)
+		}
+	}()
+	if b.query.GetModel() == nil {
+		return fmt.Errorf("model is nil")
+	}
+
+	// Execute the main query first
+	err = b.query.Scan(ctx)
+	if err != nil {
+		// Log SQL string for debugging
+		sqlStr := b.query.String()
+		logger.Error("BunSelectQuery.ScanModel failed. SQL: %s. Error: %v", sqlStr, err)
+		return err
+	}
+
+	// Execute any deferred preloads
+	if len(b.deferredPreloads) > 0 {
+		model := b.query.GetModel()
+		err = b.executeDeferredPreloads(ctx, model.Value())
+		if err != nil {
+			logger.Warn("Failed to execute deferred preloads: %v", err)
+			// Don't fail the whole query, just log the warning
+		}
+	}
+
+	return nil
 }
 
-func (b *BunSelectQuery) Count(ctx context.Context) (int, error) {
+// executeDeferredPreloads executes preloads that were deferred to avoid PostgreSQL identifier length limits
+func (b *BunSelectQuery) executeDeferredPreloads(ctx context.Context, dest interface{}) error {
+	if len(b.deferredPreloads) == 0 {
+		return nil
+	}
+
+	for _, dp := range b.deferredPreloads {
+		err := b.executeSingleDeferredPreload(ctx, dest, dp)
+		if err != nil {
+			return fmt.Errorf("failed to execute deferred preload '%s': %w", dp.relation, err)
+		}
+	}
+
+	return nil
+}
+
+// executeSingleDeferredPreload executes a single deferred preload
+// For a relation like "Parent.Child", it:
+// 1. Finds all loaded Parent records in dest
+// 2. Loads Child records for those Parents using a separate query (loading only "Child", not "Parent.Child")
+// 3. Bun automatically assigns the Child records to the appropriate Parent.Child field
+func (b *BunSelectQuery) executeSingleDeferredPreload(ctx context.Context, dest interface{}, dp deferredPreload) error {
+	relationParts := strings.Split(dp.relation, ".")
+	if len(relationParts) < 2 {
+		return fmt.Errorf("deferred preload must be nested (e.g., 'Parent.Child'), got: %s", dp.relation)
+	}
+
+	// The parent relation that was already loaded
+	parentRelation := relationParts[0]
+	// The child relation we need to load
+	childRelation := strings.Join(relationParts[1:], ".")
+
+	logger.Debug("Executing deferred preload: loading '%s' on already-loaded '%s'", childRelation, parentRelation)
+
+	// Use reflection to access the parent relation field(s) in the loaded records
+	// Then load the child relation for those parent records
+	destValue := reflect.ValueOf(dest)
+	if destValue.Kind() == reflect.Ptr {
+		destValue = destValue.Elem()
+	}
+
+	// Handle both slice and single record
+	if destValue.Kind() == reflect.Slice {
+		// Iterate through each record in the slice
+		for i := 0; i < destValue.Len(); i++ {
+			record := destValue.Index(i)
+			if err := b.loadChildRelationForRecord(ctx, record, parentRelation, childRelation, dp.apply); err != nil {
+				logger.Warn("Failed to load child relation '%s' for record %d: %v", childRelation, i, err)
+				// Continue with other records
+			}
+		}
+	} else {
+		// Single record
+		if err := b.loadChildRelationForRecord(ctx, destValue, parentRelation, childRelation, dp.apply); err != nil {
+			return fmt.Errorf("failed to load child relation '%s': %w", childRelation, err)
+		}
+	}
+
+	return nil
+}
+
+// loadChildRelationForRecord loads a child relation for a single parent record
+func (b *BunSelectQuery) loadChildRelationForRecord(ctx context.Context, record reflect.Value, parentRelation, childRelation string, apply []func(common.SelectQuery) common.SelectQuery) error {
+	// Ensure we're working with the actual struct value, not a pointer
+	if record.Kind() == reflect.Ptr {
+		record = record.Elem()
+	}
+
+	// Get the parent relation field
+	parentField := record.FieldByName(parentRelation)
+	if !parentField.IsValid() {
+		// Parent relation field doesn't exist
+		logger.Debug("Parent relation field '%s' not found in record", parentRelation)
+		return nil
+	}
+
+	// Check if the parent field is nil (for pointer fields)
+	if parentField.Kind() == reflect.Ptr && parentField.IsNil() {
+		// Parent relation not loaded or nil, skip
+		logger.Debug("Parent relation field '%s' is nil, skipping child preload", parentRelation)
+		return nil
+	}
+
+	// Get the interface value to pass to Bun
+	parentValue := parentField.Interface()
+
+	// Load the child relation on the parent record
+	// This uses a shorter alias since we're only loading "Child", not "Parent.Child"
+	return b.db.NewSelect().
+		Model(parentValue).
+		Relation(childRelation, func(sq *bun.SelectQuery) *bun.SelectQuery {
+			// Apply any custom query modifications
+			if len(apply) > 0 {
+				wrapper := &BunSelectQuery{query: sq, db: b.db}
+				current := common.SelectQuery(wrapper)
+				for _, fn := range apply {
+					if fn != nil {
+						current = fn(current)
+					}
+				}
+				if finalBun, ok := current.(*BunSelectQuery); ok {
+					return finalBun.query
+				}
+			}
+			return sq
+		}).
+		Scan(ctx)
+}
+
+func (b *BunSelectQuery) Count(ctx context.Context) (count int, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("BunSelectQuery.Count", r)
+			count = 0
+		}
+	}()
 	// If Model() was set, use bun's native Count() which works properly
 	if b.hasModel {
 		count, err := b.query.Count(ctx)
+		if err != nil {
+			// Log SQL string for debugging
+			sqlStr := b.query.String()
+			logger.Error("BunSelectQuery.Count failed. SQL: %s. Error: %v", sqlStr, err)
+		}
 		return count, err
 	}
 
 	// Otherwise, wrap as subquery to avoid "Model(nil)" error
 	// This is needed when only Table() is set without a model
-	var count int
-	err := b.db.NewSelect().
+	countQuery := b.db.NewSelect().
 		TableExpr("(?) AS subquery", b.query).
-		ColumnExpr("COUNT(*)").
-		Scan(ctx, &count)
+		ColumnExpr("COUNT(*)")
+	err = countQuery.Scan(ctx, &count)
+	if err != nil {
+		// Log SQL string for debugging
+		sqlStr := countQuery.String()
+		logger.Error("BunSelectQuery.Count (subquery) failed. SQL: %s. Error: %v", sqlStr, err)
+	}
 	return count, err
 }
 
-func (b *BunSelectQuery) Exists(ctx context.Context) (bool, error) {
-	return b.query.Exists(ctx)
+func (b *BunSelectQuery) Exists(ctx context.Context) (exists bool, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("BunSelectQuery.Exists", r)
+			exists = false
+		}
+	}()
+	exists, err = b.query.Exists(ctx)
+	if err != nil {
+		// Log SQL string for debugging
+		sqlStr := b.query.String()
+		logger.Error("BunSelectQuery.Exists failed. SQL: %s. Error: %v", sqlStr, err)
+	}
+	return exists, err
 }
 
 // BunInsertQuery implements InsertQuery for Bun
@@ -319,6 +876,9 @@ func (b *BunInsertQuery) Model(model interface{}) common.InsertQuery {
 }
 
 func (b *BunInsertQuery) Table(table string) common.InsertQuery {
+	if b.hasModel {
+		return b
+	}
 	b.query = b.query.Table(table)
 	return b
 }
@@ -343,8 +903,13 @@ func (b *BunInsertQuery) Returning(columns ...string) common.InsertQuery {
 	return b
 }
 
-func (b *BunInsertQuery) Exec(ctx context.Context) (common.Result, error) {
-	if b.values != nil && len(b.values) > 0 {
+func (b *BunInsertQuery) Exec(ctx context.Context) (res common.Result, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("BunInsertQuery.Exec", r)
+		}
+	}()
+	if len(b.values) > 0 {
 		if !b.hasModel {
 			// If no model was set, use the values map as the model
 			// Bun can insert map[string]interface{} directly
@@ -424,8 +989,18 @@ func (b *BunUpdateQuery) Returning(columns ...string) common.UpdateQuery {
 	return b
 }
 
-func (b *BunUpdateQuery) Exec(ctx context.Context) (common.Result, error) {
+func (b *BunUpdateQuery) Exec(ctx context.Context) (res common.Result, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("BunUpdateQuery.Exec", r)
+		}
+	}()
 	result, err := b.query.Exec(ctx)
+	if err != nil {
+		// Log SQL string for debugging
+		sqlStr := b.query.String()
+		logger.Error("BunUpdateQuery.Exec failed. SQL: %s. Error: %v", sqlStr, err)
+	}
 	return &BunResult{result: result}, err
 }
 
@@ -449,8 +1024,18 @@ func (b *BunDeleteQuery) Where(query string, args ...interface{}) common.DeleteQ
 	return b
 }
 
-func (b *BunDeleteQuery) Exec(ctx context.Context) (common.Result, error) {
+func (b *BunDeleteQuery) Exec(ctx context.Context) (res common.Result, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("BunDeleteQuery.Exec", r)
+		}
+	}()
 	result, err := b.query.Exec(ctx)
+	if err != nil {
+		// Log SQL string for debugging
+		sqlStr := b.query.String()
+		logger.Error("BunDeleteQuery.Exec failed. SQL: %s. Error: %v", sqlStr, err)
+	}
 	return &BunResult{result: result}, err
 }
 

pkg/common/adapters/database/gorm.go

@@ -8,6 +8,7 @@ import (
 	"gorm.io/gorm"
 
 	"github.com/bitechdev/ResolveSpec/pkg/common"
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
 	"github.com/bitechdev/ResolveSpec/pkg/modelregistry"
 	"github.com/bitechdev/ResolveSpec/pkg/reflection"
 )
@@ -22,6 +23,22 @@ func NewGormAdapter(db *gorm.DB) *GormAdapter {
 	return &GormAdapter{db: db}
 }
 
+// EnableQueryDebug enables query debugging which logs all SQL queries including preloads
+// This is useful for debugging preload queries that may be failing
+func (g *GormAdapter) EnableQueryDebug() *GormAdapter {
+	g.db = g.db.Debug()
+	logger.Info("GORM query debug mode enabled - all SQL queries will be logged")
+	return g
+}
+
+// DisableQueryDebug disables query debugging
+func (g *GormAdapter) DisableQueryDebug() *GormAdapter {
+	// GORM's Debug() creates a new session, so we need to get the base DB
+	// This is a simplified implementation
+	logger.Info("GORM debug mode - create a new adapter without Debug() to disable")
+	return g
+}
+
 func (g *GormAdapter) NewSelect() common.SelectQuery {
 	return &GormSelectQuery{db: g.db}
 }
@@ -38,12 +55,22 @@ func (g *GormAdapter) NewDelete() common.DeleteQuery {
 	return &GormDeleteQuery{db: g.db}
 }
 
-func (g *GormAdapter) Exec(ctx context.Context, query string, args ...interface{}) (common.Result, error) {
+func (g *GormAdapter) Exec(ctx context.Context, query string, args ...interface{}) (res common.Result, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("GormAdapter.Exec", r)
+		}
+	}()
 	result := g.db.WithContext(ctx).Exec(query, args...)
 	return &GormResult{result: result}, result.Error
 }
 
-func (g *GormAdapter) Query(ctx context.Context, dest interface{}, query string, args ...interface{}) error {
+func (g *GormAdapter) Query(ctx context.Context, dest interface{}, query string, args ...interface{}) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("GormAdapter.Query", r)
+		}
+	}()
 	return g.db.WithContext(ctx).Raw(query, args...).Find(dest).Error
 }
 
@@ -63,7 +90,12 @@ func (g *GormAdapter) RollbackTx(ctx context.Context) error {
 	return g.db.WithContext(ctx).Rollback().Error
 }
 
-func (g *GormAdapter) RunInTransaction(ctx context.Context, fn func(common.Database) error) error {
+func (g *GormAdapter) RunInTransaction(ctx context.Context, fn func(common.Database) error) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("GormAdapter.RunInTransaction", r)
+		}
+	}()
 	return g.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
 		adapter := &GormAdapter{db: tx}
 		return fn(adapter)
@@ -72,10 +104,12 @@ func (g *GormAdapter) RunInTransaction(ctx context.Context, fn func(common.Datab
 
 // GormSelectQuery implements SelectQuery for GORM
 type GormSelectQuery struct {
-	db         *gorm.DB
-	schema     string // Separated schema name
-	tableName  string // Just the table name, without schema
-	tableAlias string
+	db             *gorm.DB
+	schema         string // Separated schema name
+	tableName      string // Just the table name, without schema
+	tableAlias     string
+	inJoinContext  bool   // Track if we're in a JOIN relation context
+	joinTableAlias string // Alias to use for JOIN conditions
 }
 
 func (g *GormSelectQuery) Model(model interface{}) common.SelectQuery {
@@ -109,15 +143,71 @@ func (g *GormSelectQuery) Column(columns ...string) common.SelectQuery {
 }
 
 func (g *GormSelectQuery) ColumnExpr(query string, args ...interface{}) common.SelectQuery {
-	g.db = g.db.Select(query, args...)
+	if len(args) > 0 {
+		g.db = g.db.Select(query, args...)
+	} else {
+		g.db = g.db.Select(query)
+	}
+
 	return g
 }
 
 func (g *GormSelectQuery) Where(query string, args ...interface{}) common.SelectQuery {
+	// If we're in a JOIN context, add table prefix to unqualified columns
+	if g.inJoinContext && g.joinTableAlias != "" {
+		query = addTablePrefixGorm(query, g.joinTableAlias)
+	}
 	g.db = g.db.Where(query, args...)
 	return g
 }
 
+// addTablePrefixGorm adds a table prefix to unqualified column references (GORM version)
+func addTablePrefixGorm(query, tableAlias string) string {
+	if tableAlias == "" || query == "" {
+		return query
+	}
+
+	// Split on spaces and parentheses to find column references
+	parts := strings.FieldsFunc(query, func(r rune) bool {
+		return r == ' ' || r == '(' || r == ')' || r == ','
+	})
+
+	modified := query
+	for _, part := range parts {
+		// Check if this looks like an unqualified column reference
+		if !strings.Contains(part, ".") {
+			// Extract potential column name (before = or other operators)
+			for _, op := range []string{"=", "!=", "<>", ">", ">=", "<", "<=", " LIKE ", " IN ", " IS "} {
+				if strings.Contains(part, op) {
+					colName := strings.Split(part, op)[0]
+					colName = strings.TrimSpace(colName)
+					if colName != "" && !isOperatorOrKeywordGorm(colName) {
+						// Add table prefix
+						prefixed := tableAlias + "." + colName + strings.TrimPrefix(part, colName)
+						modified = strings.ReplaceAll(modified, part, prefixed)
+						logger.Debug("Adding table prefix '%s' to column '%s' in JOIN condition", tableAlias, colName)
+					}
+					break
+				}
+			}
+		}
+	}
+
+	return modified
+}
+
+// isOperatorOrKeywordGorm checks if a string is likely an operator or SQL keyword (GORM version)
+func isOperatorOrKeywordGorm(s string) bool {
+	s = strings.ToUpper(strings.TrimSpace(s))
+	keywords := []string{"AND", "OR", "NOT", "IN", "IS", "NULL", "TRUE", "FALSE", "LIKE", "BETWEEN"}
+	for _, kw := range keywords {
+		if s == kw {
+			return true
+		}
+	}
+	return false
+}
+
 func (g *GormSelectQuery) WhereOr(query string, args ...interface{}) common.SelectQuery {
 	g.db = g.db.Or(query, args...)
 	return g
@@ -201,6 +291,27 @@ func (g *GormSelectQuery) Preload(relation string, conditions ...interface{}) co
 }
 
 func (g *GormSelectQuery) PreloadRelation(relation string, apply ...func(common.SelectQuery) common.SelectQuery) common.SelectQuery {
+	// Auto-detect relationship type and choose optimal loading strategy
+	// Get the model from GORM's statement if available
+	if g.db.Statement != nil && g.db.Statement.Model != nil {
+		relType := reflection.GetRelationType(g.db.Statement.Model, relation)
+
+		// Log the detected relationship type
+		logger.Debug("PreloadRelation '%s' detected as: %s", relation, relType)
+
+		// If this is a belongs-to or has-one relation, use JOIN for better performance
+		if relType.ShouldUseJoin() {
+			logger.Info("Using JOIN strategy for %s relation '%s'", relType, relation)
+			return g.JoinRelation(relation, apply...)
+		}
+
+		// For has-many, many-to-many, or unknown: use separate query (safer default)
+		if relType == reflection.RelationHasMany || relType == reflection.RelationManyToMany {
+			logger.Debug("Using separate query for %s relation '%s'", relType, relation)
+		}
+	}
+
+	// Use GORM's Preload (separate query strategy)
 	g.db = g.db.Preload(relation, func(db *gorm.DB) *gorm.DB {
 		if len(apply) == 0 {
 			return db
@@ -230,6 +341,42 @@ func (g *GormSelectQuery) PreloadRelation(relation string, apply ...func(common.
 	return g
 }
 
+func (g *GormSelectQuery) JoinRelation(relation string, apply ...func(common.SelectQuery) common.SelectQuery) common.SelectQuery {
+	// JoinRelation uses a JOIN instead of a separate preload query
+	// This is more efficient for many-to-one or one-to-one relationships
+	// as it avoids additional round trips to the database
+
+	// GORM's Joins() method forces a JOIN for the preload
+	logger.Debug("JoinRelation '%s' - Using GORM Joins() with automatic WHERE prefix addition", relation)
+
+	g.db = g.db.Joins(relation, func(db *gorm.DB) *gorm.DB {
+		if len(apply) == 0 {
+			return db
+		}
+
+		wrapper := &GormSelectQuery{
+			db:             db,
+			inJoinContext:  true,                      // Mark as JOIN context
+			joinTableAlias: strings.ToLower(relation), // Use relation name as alias
+		}
+		current := common.SelectQuery(wrapper)
+
+		for _, fn := range apply {
+			if fn != nil {
+				current = fn(current)
+			}
+		}
+
+		if finalGorm, ok := current.(*GormSelectQuery); ok {
+			return finalGorm.db
+		}
+
+		return db
+	})
+
+	return g
+}
+
 func (g *GormSelectQuery) Order(order string) common.SelectQuery {
 	g.db = g.db.Order(order)
 	return g
@@ -255,26 +402,78 @@ func (g *GormSelectQuery) Having(having string, args ...interface{}) common.Sele
 	return g
 }
 
-func (g *GormSelectQuery) Scan(ctx context.Context, dest interface{}) error {
-	return g.db.WithContext(ctx).Find(dest).Error
+func (g *GormSelectQuery) Scan(ctx context.Context, dest interface{}) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("GormSelectQuery.Scan", r)
+		}
+	}()
+	err = g.db.WithContext(ctx).Find(dest).Error
+	if err != nil {
+		// Log SQL string for debugging
+		sqlStr := g.db.ToSQL(func(tx *gorm.DB) *gorm.DB {
+			return tx.Find(dest)
+		})
+		logger.Error("GormSelectQuery.Scan failed. SQL: %s. Error: %v", sqlStr, err)
+	}
+	return err
 }
 
-func (g *GormSelectQuery) ScanModel(ctx context.Context) error {
+func (g *GormSelectQuery) ScanModel(ctx context.Context) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("GormSelectQuery.ScanModel", r)
+		}
+	}()
 	if g.db.Statement.Model == nil {
 		return fmt.Errorf("ScanModel requires Model() to be set before scanning")
 	}
-	return g.db.WithContext(ctx).Find(g.db.Statement.Model).Error
+	err = g.db.WithContext(ctx).Find(g.db.Statement.Model).Error
+	if err != nil {
+		// Log SQL string for debugging
+		sqlStr := g.db.ToSQL(func(tx *gorm.DB) *gorm.DB {
+			return tx.Find(g.db.Statement.Model)
+		})
+		logger.Error("GormSelectQuery.ScanModel failed. SQL: %s. Error: %v", sqlStr, err)
+	}
+	return err
 }
 
-func (g *GormSelectQuery) Count(ctx context.Context) (int, error) {
-	var count int64
-	err := g.db.WithContext(ctx).Count(&count).Error
-	return int(count), err
+func (g *GormSelectQuery) Count(ctx context.Context) (count int, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("GormSelectQuery.Count", r)
+			count = 0
+		}
+	}()
+	var count64 int64
+	err = g.db.WithContext(ctx).Count(&count64).Error
+	if err != nil {
+		// Log SQL string for debugging
+		sqlStr := g.db.ToSQL(func(tx *gorm.DB) *gorm.DB {
+			return tx.Count(&count64)
+		})
+		logger.Error("GormSelectQuery.Count failed. SQL: %s. Error: %v", sqlStr, err)
+	}
+	return int(count64), err
 }
 
-func (g *GormSelectQuery) Exists(ctx context.Context) (bool, error) {
+func (g *GormSelectQuery) Exists(ctx context.Context) (exists bool, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("GormSelectQuery.Exists", r)
+			exists = false
+		}
+	}()
 	var count int64
-	err := g.db.WithContext(ctx).Limit(1).Count(&count).Error
+	err = g.db.WithContext(ctx).Limit(1).Count(&count).Error
+	if err != nil {
+		// Log SQL string for debugging
+		sqlStr := g.db.ToSQL(func(tx *gorm.DB) *gorm.DB {
+			return tx.Limit(1).Count(&count)
+		})
+		logger.Error("GormSelectQuery.Exists failed. SQL: %s. Error: %v", sqlStr, err)
+	}
 	return count > 0, err
 }
 
@@ -314,7 +513,12 @@ func (g *GormInsertQuery) Returning(columns ...string) common.InsertQuery {
 	return g
 }
 
-func (g *GormInsertQuery) Exec(ctx context.Context) (common.Result, error) {
+func (g *GormInsertQuery) Exec(ctx context.Context) (res common.Result, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("GormInsertQuery.Exec", r)
+		}
+	}()
 	var result *gorm.DB
 	switch {
 	case g.model != nil:
@@ -401,8 +605,20 @@ func (g *GormUpdateQuery) Returning(columns ...string) common.UpdateQuery {
 	return g
 }
 
-func (g *GormUpdateQuery) Exec(ctx context.Context) (common.Result, error) {
+func (g *GormUpdateQuery) Exec(ctx context.Context) (res common.Result, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("GormUpdateQuery.Exec", r)
+		}
+	}()
 	result := g.db.WithContext(ctx).Updates(g.updates)
+	if result.Error != nil {
+		// Log SQL string for debugging
+		sqlStr := g.db.ToSQL(func(tx *gorm.DB) *gorm.DB {
+			return tx.Updates(g.updates)
+		})
+		logger.Error("GormUpdateQuery.Exec failed. SQL: %s. Error: %v", sqlStr, result.Error)
+	}
 	return &GormResult{result: result}, result.Error
 }
 
@@ -428,8 +644,20 @@ func (g *GormDeleteQuery) Where(query string, args ...interface{}) common.Delete
 	return g
 }
 
-func (g *GormDeleteQuery) Exec(ctx context.Context) (common.Result, error) {
+func (g *GormDeleteQuery) Exec(ctx context.Context) (res common.Result, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = logger.HandlePanic("GormDeleteQuery.Exec", r)
+		}
+	}()
 	result := g.db.WithContext(ctx).Delete(g.model)
+	if result.Error != nil {
+		// Log SQL string for debugging
+		sqlStr := g.db.ToSQL(func(tx *gorm.DB) *gorm.DB {
+			return tx.Delete(g.model)
+		})
+		logger.Error("GormDeleteQuery.Exec failed. SQL: %s. Error: %v", sqlStr, result.Error)
+	}
 	return &GormResult{result: result}, result.Error
 }
 

pkg/common/adapters/router/bunrouter.go

@@ -6,6 +6,7 @@ import (
 	"github.com/uptrace/bunrouter"
 
 	"github.com/bitechdev/ResolveSpec/pkg/common"
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
 )
 
 // BunRouterAdapter adapts uptrace/bunrouter to work with our Router interface
@@ -35,7 +36,11 @@ func (b *BunRouterAdapter) HandleFunc(pattern string, handler common.HTTPHandler
 func (b *BunRouterAdapter) ServeHTTP(w common.ResponseWriter, r common.Request) {
 	// This method would be used when we need to serve through our interface
 	// For now, we'll work directly with the underlying router
-	panic("ServeHTTP not implemented - use GetBunRouter() for direct access")
+	w.WriteHeader(http.StatusNotImplemented)
+	_, err := w.Write([]byte(`{"error":"ServeHTTP not implemented - use GetBunRouter() for direct access"}`))
+	if err != nil {
+		logger.Warn("Failed to write. %v", err)
+	}
 }
 
 // GetBunRouter returns the underlying bunrouter for direct access
@@ -121,6 +126,16 @@ func (b *BunRouterRequest) QueryParam(key string) string {
 	return b.req.URL.Query().Get(key)
 }
 
+func (b *BunRouterRequest) AllQueryParams() map[string]string {
+	params := make(map[string]string)
+	for key, values := range b.req.URL.Query() {
+		if len(values) > 0 {
+			params[key] = values[0]
+		}
+	}
+	return params
+}
+
 func (b *BunRouterRequest) AllHeaders() map[string]string {
 	headers := make(map[string]string)
 	for key, values := range b.req.Header {
@@ -131,6 +146,12 @@ func (b *BunRouterRequest) AllHeaders() map[string]string {
 	return headers
 }
 
+// UnderlyingRequest returns the underlying *http.Request
+// This is useful when you need to pass the request to other handlers
+func (b *BunRouterRequest) UnderlyingRequest() *http.Request {
+	return b.req.Request
+}
+
 // StandardBunRouterAdapter creates routes compatible with standard bunrouter handlers
 type StandardBunRouterAdapter struct {
 	*BunRouterAdapter

pkg/common/adapters/router/mux.go

@@ -8,6 +8,7 @@ import (
 	"github.com/gorilla/mux"
 
 	"github.com/bitechdev/ResolveSpec/pkg/common"
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
 )
 
 // MuxAdapter adapts Gorilla Mux to work with our Router interface
@@ -32,7 +33,11 @@ func (m *MuxAdapter) HandleFunc(pattern string, handler common.HTTPHandlerFunc)
 func (m *MuxAdapter) ServeHTTP(w common.ResponseWriter, r common.Request) {
 	// This method would be used when we need to serve through our interface
 	// For now, we'll work directly with the underlying router
-	panic("ServeHTTP not implemented - use GetMuxRouter() for direct access")
+	w.WriteHeader(http.StatusNotImplemented)
+	_, err := w.Write([]byte(`{"error":"ServeHTTP not implemented - use GetMuxRouter() for direct access"}`))
+	if err != nil {
+		logger.Warn("Failed to write. %v", err)
+	}
 }
 
 // MuxRouteRegistration implements RouteRegistration for Mux
@@ -117,6 +122,16 @@ func (h *HTTPRequest) QueryParam(key string) string {
 	return h.req.URL.Query().Get(key)
 }
 
+func (h *HTTPRequest) AllQueryParams() map[string]string {
+	params := make(map[string]string)
+	for key, values := range h.req.URL.Query() {
+		if len(values) > 0 {
+			params[key] = values[0]
+		}
+	}
+	return params
+}
+
 func (h *HTTPRequest) AllHeaders() map[string]string {
 	headers := make(map[string]string)
 	for key, values := range h.req.Header {
@@ -127,6 +142,12 @@ func (h *HTTPRequest) AllHeaders() map[string]string {
 	return headers
 }
 
+// UnderlyingRequest returns the underlying *http.Request
+// This is useful when you need to pass the request to other handlers
+func (h *HTTPRequest) UnderlyingRequest() *http.Request {
+	return h.req
+}
+
 // HTTPResponseWriter adapts our ResponseWriter interface to standard http.ResponseWriter
 type HTTPResponseWriter struct {
 	resp   http.ResponseWriter
@@ -156,6 +177,12 @@ func (h *HTTPResponseWriter) WriteJSON(data interface{}) error {
 	return json.NewEncoder(h.resp).Encode(data)
 }
 
+// UnderlyingResponseWriter returns the underlying http.ResponseWriter
+// This is useful when you need to pass the response writer to other handlers
+func (h *HTTPResponseWriter) UnderlyingResponseWriter() http.ResponseWriter {
+	return h.resp
+}
+
 // StandardMuxAdapter creates routes compatible with standard http.HandlerFunc
 type StandardMuxAdapter struct {
 	*MuxAdapter

pkg/common/cors.go

@@ -0,0 +1,119 @@
+package common
+
+import (
+	"fmt"
+	"strings"
+)
+
+// CORSConfig holds CORS configuration
+type CORSConfig struct {
+	AllowedOrigins []string
+	AllowedMethods []string
+	AllowedHeaders []string
+	MaxAge         int
+}
+
+// DefaultCORSConfig returns a default CORS configuration suitable for HeadSpec
+func DefaultCORSConfig() CORSConfig {
+	return CORSConfig{
+		AllowedOrigins: []string{"*"},
+		AllowedMethods: []string{"GET", "POST", "PUT", "PATCH", "DELETE", "OPTIONS"},
+		AllowedHeaders: GetHeadSpecHeaders(),
+		MaxAge:         86400, // 24 hours
+	}
+}
+
+// GetHeadSpecHeaders returns all headers used by HeadSpec
+func GetHeadSpecHeaders() []string {
+	return []string{
+		// Standard headers
+		"Content-Type",
+		"Authorization",
+		"Accept",
+		"Accept-Language",
+		"Content-Language",
+
+		// Field Selection
+		"X-Select-Fields",
+		"X-Not-Select-Fields",
+		"X-Clean-JSON",
+
+		// Filtering & Search
+		"X-FieldFilter-*",
+		"X-SearchFilter-*",
+		"X-SearchOp-*",
+		"X-SearchOr-*",
+		"X-SearchAnd-*",
+		"X-SearchCols",
+		"X-Custom-SQL-W",
+		"X-Custom-SQL-W-*",
+		"X-Custom-SQL-Or",
+		"X-Custom-SQL-Or-*",
+
+		// Joins & Relations
+		"X-Preload",
+		"X-Preload-*",
+		"X-Expand",
+		"X-Expand-*",
+		"X-Custom-SQL-Join",
+		"X-Custom-SQL-Join-*",
+
+		// Sorting & Pagination
+		"X-Sort",
+		"X-Sort-*",
+		"X-Limit",
+		"X-Offset",
+		"X-Cursor-Forward",
+		"X-Cursor-Backward",
+
+		// Advanced Features
+		"X-AdvSQL-*",
+		"X-CQL-Sel-*",
+		"X-Distinct",
+		"X-SkipCount",
+		"X-SkipCache",
+		"X-Fetch-RowNumber",
+		"X-PKRow",
+
+		// Response Format
+		"X-SimpleAPI",
+		"X-DetailAPI",
+		"X-Syncfusion",
+		"X-Single-Record-As-Object",
+
+		// Transaction Control
+		"X-Transaction-Atomic",
+
+		// X-Files - comprehensive JSON configuration
+		"X-Files",
+	}
+}
+
+// SetCORSHeaders sets CORS headers on a response writer
+func SetCORSHeaders(w ResponseWriter, config CORSConfig) {
+	// Set allowed origins
+	if len(config.AllowedOrigins) > 0 {
+		w.SetHeader("Access-Control-Allow-Origin", strings.Join(config.AllowedOrigins, ", "))
+	}
+
+	// Set allowed methods
+	if len(config.AllowedMethods) > 0 {
+		w.SetHeader("Access-Control-Allow-Methods", strings.Join(config.AllowedMethods, ", "))
+	}
+
+	// Set allowed headers
+	if len(config.AllowedHeaders) > 0 {
+		w.SetHeader("Access-Control-Allow-Headers", strings.Join(config.AllowedHeaders, ", "))
+	}
+
+	// Set max age
+	if config.MaxAge > 0 {
+		w.SetHeader("Access-Control-Max-Age", fmt.Sprintf("%d", config.MaxAge))
+	}
+
+	// Allow credentials
+	w.SetHeader("Access-Control-Allow-Credentials", "true")
+
+	// Expose headers that clients can read
+	w.SetHeader("Access-Control-Expose-Headers", "Content-Range, X-Api-Range-Total, X-Api-Range-Size")
+}

pkg/common/handler_example.go

@@ -0,0 +1,97 @@
+package common
+
+// Example showing how to use the common handler interfaces
+// This file demonstrates the handler interface hierarchy and usage patterns
+
+// ProcessWithAnyHandler demonstrates using the base SpecHandler interface
+// which works with any handler type (resolvespec, restheadspec, or funcspec)
+func ProcessWithAnyHandler(handler SpecHandler) Database {
+	// All handlers expose GetDatabase() through the SpecHandler interface
+	return handler.GetDatabase()
+}
+
+// ProcessCRUDRequest demonstrates using the CRUDHandler interface
+// which works with resolvespec.Handler and restheadspec.Handler
+func ProcessCRUDRequest(handler CRUDHandler, w ResponseWriter, r Request, params map[string]string) {
+	// Both resolvespec and restheadspec handlers implement Handle()
+	handler.Handle(w, r, params)
+}
+
+// ProcessMetadataRequest demonstrates getting metadata from CRUD handlers
+func ProcessMetadataRequest(handler CRUDHandler, w ResponseWriter, r Request, params map[string]string) {
+	// Both resolvespec and restheadspec handlers implement HandleGet()
+	handler.HandleGet(w, r, params)
+}
+
+// Example usage patterns (not executable, just for documentation):
+/*
+// Example 1: Using with resolvespec.Handler
+func ExampleResolveSpec() {
+	db := // ... get database
+	registry := // ... get registry
+
+	handler := resolvespec.NewHandler(db, registry)
+
+	// Can be used as SpecHandler
+	var specHandler SpecHandler = handler
+	database := specHandler.GetDatabase()
+
+	// Can be used as CRUDHandler
+	var crudHandler CRUDHandler = handler
+	crudHandler.Handle(w, r, params)
+	crudHandler.HandleGet(w, r, params)
+}
+
+// Example 2: Using with restheadspec.Handler
+func ExampleRestHeadSpec() {
+	db := // ... get database
+	registry := // ... get registry
+
+	handler := restheadspec.NewHandler(db, registry)
+
+	// Can be used as SpecHandler
+	var specHandler SpecHandler = handler
+	database := specHandler.GetDatabase()
+
+	// Can be used as CRUDHandler
+	var crudHandler CRUDHandler = handler
+	crudHandler.Handle(w, r, params)
+	crudHandler.HandleGet(w, r, params)
+}
+
+// Example 3: Using with funcspec.Handler
+func ExampleFuncSpec() {
+	db := // ... get database
+
+	handler := funcspec.NewHandler(db)
+
+	// Can be used as SpecHandler
+	var specHandler SpecHandler = handler
+	database := specHandler.GetDatabase()
+
+	// Can be used as QueryHandler
+	var queryHandler QueryHandler = handler
+	// funcspec has different methods: SqlQueryList() and SqlQuery()
+	// which return HTTP handler functions
+}
+
+// Example 4: Polymorphic handler processing
+func ProcessHandlers(handlers []SpecHandler) {
+	for _, handler := range handlers {
+		// All handlers expose the database
+		db := handler.GetDatabase()
+
+		// Type switch for specific handler types
+		switch h := handler.(type) {
+		case CRUDHandler:
+			// This is resolvespec or restheadspec
+			// Can call Handle() and HandleGet()
+			_ = h
+		case QueryHandler:
+			// This is funcspec
+			// Can call SqlQueryList() and SqlQuery()
+			_ = h
+		}
+	}
+}
+*/

pkg/common/handler_utils.go

@@ -0,0 +1,47 @@
+package common
+
+import (
+	"fmt"
+	"reflect"
+)
+
+// ValidateAndUnwrapModelResult contains the result of model validation
+type ValidateAndUnwrapModelResult struct {
+	ModelType    reflect.Type
+	Model        interface{}
+	ModelPtr     interface{}
+	OriginalType reflect.Type
+}
+
+// ValidateAndUnwrapModel validates that a model is a struct type and unwraps
+// pointers, slices, and arrays to get to the base struct type.
+// Returns an error if the model is not a valid struct type.
+func ValidateAndUnwrapModel(model interface{}) (*ValidateAndUnwrapModelResult, error) {
+	modelType := reflect.TypeOf(model)
+	originalType := modelType
+
+	// Unwrap pointers, slices, and arrays to get to the base struct type
+	for modelType != nil && (modelType.Kind() == reflect.Ptr || modelType.Kind() == reflect.Slice || modelType.Kind() == reflect.Array) {
+		modelType = modelType.Elem()
+	}
+
+	// Validate that we have a struct type
+	if modelType == nil || modelType.Kind() != reflect.Struct {
+		return nil, fmt.Errorf("model must be a struct type, got %v. Ensure you register the struct (e.g., ModelCoreAccount{}) not a slice (e.g., []*ModelCoreAccount)", originalType)
+	}
+
+	// If the registered model was a pointer or slice, use the unwrapped struct type
+	if originalType != modelType {
+		model = reflect.New(modelType).Elem().Interface()
+	}
+
+	// Create a pointer to the model type for database operations
+	modelPtr := reflect.New(reflect.TypeOf(model)).Interface()
+
+	return &ValidateAndUnwrapModelResult{
+		ModelType:    modelType,
+		Model:        model,
+		ModelPtr:     modelPtr,
+		OriginalType: originalType,
+	}, nil
+}

pkg/common/interfaces.go

@@ -1,6 +1,11 @@
 package common
 
-import "context"
+import (
+	"context"
+	"encoding/json"
+	"io"
+	"net/http"
+)
 
 // Database interface designed to work with both GORM and Bun
 type Database interface {
@@ -33,6 +38,7 @@ type SelectQuery interface {
 	LeftJoin(query string, args ...interface{}) SelectQuery
 	Preload(relation string, conditions ...interface{}) SelectQuery
 	PreloadRelation(relation string, apply ...func(SelectQuery) SelectQuery) SelectQuery
+	JoinRelation(relation string, apply ...func(SelectQuery) SelectQuery) SelectQuery
 	Order(order string) SelectQuery
 	Limit(n int) SelectQuery
 	Offset(n int) SelectQuery
@@ -116,6 +122,8 @@ type Request interface {
 	Body() ([]byte, error)
 	PathParam(key string) string
 	QueryParam(key string) string
+	AllQueryParams() map[string]string // Get all query parameters as a map
+	UnderlyingRequest() *http.Request  // Get the underlying *http.Request for forwarding to other handlers
 }
 
 // ResponseWriter interface abstracts HTTP response
@@ -124,11 +132,113 @@ type ResponseWriter interface {
 	WriteHeader(statusCode int)
 	Write(data []byte) (int, error)
 	WriteJSON(data interface{}) error
+	UnderlyingResponseWriter() http.ResponseWriter // Get the underlying http.ResponseWriter for forwarding to other handlers
 }
 
 // HTTPHandlerFunc type for HTTP handlers
 type HTTPHandlerFunc func(ResponseWriter, Request)
 
+// WrapHTTPRequest wraps standard http.ResponseWriter and *http.Request into common interfaces
+func WrapHTTPRequest(w http.ResponseWriter, r *http.Request) (ResponseWriter, Request) {
+	return &StandardResponseWriter{w: w}, &StandardRequest{r: r}
+}
+
+// StandardResponseWriter adapts http.ResponseWriter to ResponseWriter interface
+type StandardResponseWriter struct {
+	w      http.ResponseWriter
+	status int
+}
+
+func (s *StandardResponseWriter) SetHeader(key, value string) {
+	s.w.Header().Set(key, value)
+}
+
+func (s *StandardResponseWriter) WriteHeader(statusCode int) {
+	s.status = statusCode
+	s.w.WriteHeader(statusCode)
+}
+
+func (s *StandardResponseWriter) Write(data []byte) (int, error) {
+	return s.w.Write(data)
+}
+
+func (s *StandardResponseWriter) WriteJSON(data interface{}) error {
+	s.SetHeader("Content-Type", "application/json")
+	return json.NewEncoder(s.w).Encode(data)
+}
+
+func (s *StandardResponseWriter) UnderlyingResponseWriter() http.ResponseWriter {
+	return s.w
+}
+
+// StandardRequest adapts *http.Request to Request interface
+type StandardRequest struct {
+	r    *http.Request
+	body []byte
+}
+
+func (s *StandardRequest) Method() string {
+	return s.r.Method
+}
+
+func (s *StandardRequest) URL() string {
+	return s.r.URL.String()
+}
+
+func (s *StandardRequest) Header(key string) string {
+	return s.r.Header.Get(key)
+}
+
+func (s *StandardRequest) AllHeaders() map[string]string {
+	headers := make(map[string]string)
+	for key, values := range s.r.Header {
+		if len(values) > 0 {
+			headers[key] = values[0]
+		}
+	}
+	return headers
+}
+
+func (s *StandardRequest) Body() ([]byte, error) {
+	if s.body != nil {
+		return s.body, nil
+	}
+	if s.r.Body == nil {
+		return nil, nil
+	}
+	defer s.r.Body.Close()
+	body, err := io.ReadAll(s.r.Body)
+	if err != nil {
+		return nil, err
+	}
+	s.body = body
+	return body, nil
+}
+
+func (s *StandardRequest) PathParam(key string) string {
+	// Standard http.Request doesn't have path params
+	// This should be set by the router
+	return ""
+}
+
+func (s *StandardRequest) QueryParam(key string) string {
+	return s.r.URL.Query().Get(key)
+}
+
+func (s *StandardRequest) AllQueryParams() map[string]string {
+	params := make(map[string]string)
+	for key, values := range s.r.URL.Query() {
+		if len(values) > 0 {
+			params[key] = values[0]
+		}
+	}
+	return params
+}
+
+func (s *StandardRequest) UnderlyingRequest() *http.Request {
+	return s.r
+}
+
 // TableNameProvider interface for models that provide table names
 type TableNameProvider interface {
 	TableName() string
@@ -147,3 +257,39 @@ type PrimaryKeyNameProvider interface {
 type SchemaProvider interface {
 	SchemaName() string
 }
+
+// SpecHandler interface represents common functionality across all spec handlers
+// This is the base interface implemented by:
+//   - resolvespec.Handler: Handles CRUD operations via request body with explicit operation field
+//   - restheadspec.Handler: Handles CRUD operations via HTTP methods (GET/POST/PUT/DELETE)
+//   - funcspec.Handler: Handles custom SQL query execution with dynamic parameters
+//
+// The interface hierarchy is:
+//
+//	SpecHandler (base)
+//	├── CRUDHandler (resolvespec, restheadspec)
+//	└── QueryHandler (funcspec)
+type SpecHandler interface {
+	// GetDatabase returns the underlying database connection
+	GetDatabase() Database
+}
+
+// CRUDHandler interface for handlers that support CRUD operations
+// This is implemented by resolvespec.Handler and restheadspec.Handler
+type CRUDHandler interface {
+	SpecHandler
+
+	// Handle processes API requests through router-agnostic interface
+	Handle(w ResponseWriter, r Request, params map[string]string)
+
+	// HandleGet processes GET requests for metadata
+	HandleGet(w ResponseWriter, r Request, params map[string]string)
+}
+
+// QueryHandler interface for handlers that execute SQL queries
+// This is implemented by funcspec.Handler
+// Note: funcspec uses standard http.ResponseWriter and *http.Request instead of common interfaces
+type QueryHandler interface {
+	SpecHandler
+	// Methods are defined in funcspec package due to different function signature requirements
+}

pkg/common/sql_helpers.go

@@ -0,0 +1,367 @@
+package common
+
+import (
+	"strings"
+
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
+	"github.com/bitechdev/ResolveSpec/pkg/modelregistry"
+	"github.com/bitechdev/ResolveSpec/pkg/reflection"
+)
+
+// ValidateAndFixPreloadWhere validates and normalizes WHERE clauses for preloads
+//
+// NOTE: For preload queries, table aliases from the parent query are not valid since
+// the preload executes as a separate query with its own table alias. This function
+// now simply validates basic syntax without requiring or adding prefixes.
+// The actual alias normalization happens in the database adapter layer.
+//
+// Returns the WHERE clause and an error if it contains obviously invalid syntax.
+func ValidateAndFixPreloadWhere(where string, relationName string) (string, error) {
+	if where == "" {
+		return where, nil
+	}
+
+	where = strings.TrimSpace(where)
+
+	// Just do basic validation - don't require or add prefixes
+	// The database adapter will handle alias normalization
+
+	// Check if the WHERE clause contains any qualified column references
+	// If it does, log a debug message but don't fail - let the adapter handle it
+	if strings.Contains(where, ".") {
+		logger.Debug("Preload WHERE clause for '%s' contains qualified column references: '%s'. "+
+			"Note: In preload context, table aliases from parent query are not available. "+
+			"The database adapter will normalize aliases automatically.", relationName, where)
+	}
+
+	// Validate that it's not empty or just whitespace
+	if where == "" {
+		return where, nil
+	}
+
+	// Return the WHERE clause as-is
+	// The BunSelectQuery.Where() method will handle alias normalization via normalizeTableAlias()
+	return where, nil
+}
+
+// IsSQLExpression checks if a condition is a SQL expression that shouldn't be prefixed
+func IsSQLExpression(cond string) bool {
+	// Common SQL literals and expressions
+	sqlLiterals := []string{"true", "false", "null", "1=1", "1 = 1", "0=0", "0 = 0"}
+	for _, literal := range sqlLiterals {
+		if cond == literal {
+			return true
+		}
+	}
+	return false
+}
+
+// IsTrivialCondition checks if a condition is trivial and always evaluates to true
+// These conditions should be removed from WHERE clauses as they have no filtering effect
+func IsTrivialCondition(cond string) bool {
+	cond = strings.TrimSpace(cond)
+	lowerCond := strings.ToLower(cond)
+
+	// Conditions that always evaluate to true
+	trivialConditions := []string{
+		"1=1", "1 = 1", "1= 1", "1 =1",
+		"true", "true = true", "true=true", "true= true", "true =true",
+		"0=0", "0 = 0", "0= 0", "0 =0",
+	}
+
+	for _, trivial := range trivialConditions {
+		if lowerCond == trivial {
+			return true
+		}
+	}
+
+	return false
+}
+
+// SanitizeWhereClause removes trivial conditions and fixes incorrect table prefixes
+// This function should be used everywhere a WHERE statement is sent to ensure clean, efficient SQL
+//
+// Parameters:
+//   - where: The WHERE clause string to sanitize
+//   - tableName: The correct table/relation name to use when fixing incorrect prefixes
+//   - options: Optional RequestOptions containing preload relations that should be allowed as valid prefixes
+//
+// Returns:
+//   - The sanitized WHERE clause with trivial conditions removed and incorrect prefixes fixed
+//   - An empty string if all conditions were trivial or the input was empty
+//
+// Note: This function will NOT add prefixes to unprefixed columns. It will only fix
+// incorrect prefixes (e.g., wrong_table.column -> correct_table.column), unless the
+// prefix matches a preloaded relation name, in which case it's left unchanged.
+func SanitizeWhereClause(where string, tableName string, options ...*RequestOptions) string {
+	if where == "" {
+		return ""
+	}
+
+	where = strings.TrimSpace(where)
+
+	// Strip outer parentheses and re-trim
+	where = stripOuterParentheses(where)
+
+	// Get valid columns from the model if tableName is provided
+	var validColumns map[string]bool
+	if tableName != "" {
+		validColumns = getValidColumnsForTable(tableName)
+	}
+
+	// Build a set of allowed table prefixes (main table + preloaded relations)
+	allowedPrefixes := make(map[string]bool)
+	if tableName != "" {
+		allowedPrefixes[tableName] = true
+	}
+
+	// Add preload relation names as allowed prefixes
+	if len(options) > 0 && options[0] != nil {
+		for pi := range options[0].Preload {
+			if options[0].Preload[pi].Relation != "" {
+				allowedPrefixes[options[0].Preload[pi].Relation] = true
+				logger.Debug("Added preload relation '%s' as allowed table prefix", options[0].Preload[pi].Relation)
+			}
+		}
+	}
+
+	// Split by AND to handle multiple conditions
+	conditions := splitByAND(where)
+
+	validConditions := make([]string, 0, len(conditions))
+
+	for _, cond := range conditions {
+		cond = strings.TrimSpace(cond)
+		if cond == "" {
+			continue
+		}
+
+		// Strip parentheses from the condition before checking
+		condToCheck := stripOuterParentheses(cond)
+
+		// Skip trivial conditions that always evaluate to true
+		if IsTrivialCondition(condToCheck) {
+			logger.Debug("Removing trivial condition: '%s'", cond)
+			continue
+		}
+
+		// If tableName is provided and the condition HAS a table prefix, check if it's correct
+		if tableName != "" && hasTablePrefix(condToCheck) {
+			// Extract the current prefix and column name
+			currentPrefix, columnName := extractTableAndColumn(condToCheck)
+
+			if currentPrefix != "" && columnName != "" {
+				// Check if the prefix is allowed (main table or preload relation)
+				if !allowedPrefixes[currentPrefix] {
+					// Prefix is not in the allowed list - only fix if it's a valid column in the main table
+					if validColumns == nil || isValidColumn(columnName, validColumns) {
+						// Replace the incorrect prefix with the correct main table name
+						oldRef := currentPrefix + "." + columnName
+						newRef := tableName + "." + columnName
+						cond = strings.Replace(cond, oldRef, newRef, 1)
+						logger.Debug("Fixed incorrect table prefix in condition: '%s' -> '%s'", oldRef, newRef)
+					} else {
+						logger.Debug("Skipping prefix fix for '%s.%s' - not a valid column in main table (might be preload relation)", currentPrefix, columnName)
+					}
+				}
+			}
+		}
+
+		validConditions = append(validConditions, cond)
+	}
+
+	if len(validConditions) == 0 {
+		return ""
+	}
+
+	result := strings.Join(validConditions, " AND ")
+
+	if result != where {
+		logger.Debug("Sanitized WHERE clause: '%s' -> '%s'", where, result)
+	}
+
+	return result
+}
+
+// stripOuterParentheses removes matching outer parentheses from a string
+// It handles nested parentheses correctly
+func stripOuterParentheses(s string) string {
+	s = strings.TrimSpace(s)
+
+	for {
+		if len(s) < 2 || s[0] != '(' || s[len(s)-1] != ')' {
+			return s
+		}
+
+		// Check if these parentheses match (i.e., they're the outermost pair)
+		depth := 0
+		matched := false
+		for i := 0; i < len(s); i++ {
+			switch s[i] {
+			case '(':
+				depth++
+			case ')':
+				depth--
+				if depth == 0 && i == len(s)-1 {
+					matched = true
+				} else if depth == 0 {
+					// Found a closing paren before the end, so outer parens don't match
+					return s
+				}
+			}
+		}
+
+		if !matched {
+			return s
+		}
+
+		// Strip the outer parentheses and continue
+		s = strings.TrimSpace(s[1 : len(s)-1])
+	}
+}
+
+// splitByAND splits a WHERE clause by AND operators (case-insensitive)
+// This is a simple split that doesn't handle nested parentheses or complex expressions
+func splitByAND(where string) []string {
+	// First try uppercase AND
+	conditions := strings.Split(where, " AND ")
+
+	// If we didn't split on uppercase, try lowercase
+	if len(conditions) == 1 {
+		conditions = strings.Split(where, " and ")
+	}
+
+	// If we still didn't split, try mixed case
+	if len(conditions) == 1 {
+		conditions = strings.Split(where, " And ")
+	}
+
+	return conditions
+}
+
+// hasTablePrefix checks if a condition already has a table/relation prefix (contains a dot)
+func hasTablePrefix(cond string) bool {
+	// Look for patterns like "table.column" or "`table`.`column`" or "\"table\".\"column\""
+	return strings.Contains(cond, ".")
+}
+
+// ExtractColumnName extracts the column name from a WHERE condition
+// For example: "status = 'active'" returns "status"
+func ExtractColumnName(cond string) string {
+	// Common SQL operators
+	operators := []string{" = ", " != ", " <> ", " > ", " >= ", " < ", " <= ", " LIKE ", " like ", " IN ", " in ", " IS ", " is "}
+
+	for _, op := range operators {
+		if idx := strings.Index(cond, op); idx > 0 {
+			columnName := strings.TrimSpace(cond[:idx])
+			// Remove quotes if present
+			columnName = strings.Trim(columnName, "`\"'")
+			return columnName
+		}
+	}
+
+	// If no operator found, check if it's a simple identifier (for boolean columns)
+	parts := strings.Fields(cond)
+	if len(parts) > 0 {
+		columnName := strings.Trim(parts[0], "`\"'")
+		// Check if it's a valid identifier (not a SQL keyword)
+		if !IsSQLKeyword(strings.ToLower(columnName)) {
+			return columnName
+		}
+	}
+
+	return ""
+}
+
+// IsSQLKeyword checks if a string is a SQL keyword that shouldn't be treated as a column name
+func IsSQLKeyword(word string) bool {
+	keywords := []string{"select", "from", "where", "and", "or", "not", "in", "is", "null", "true", "false", "like", "between", "exists"}
+	for _, kw := range keywords {
+		if word == kw {
+			return true
+		}
+	}
+	return false
+}
+
+// getValidColumnsForTable retrieves the valid SQL columns for a table from the model registry
+// Returns a map of column names for fast lookup, or nil if the model is not found
+func getValidColumnsForTable(tableName string) map[string]bool {
+	// Try to get the model from the registry
+	model, err := modelregistry.GetModelByName(tableName)
+	if err != nil {
+		// Model not found, return nil to indicate we should use fallback behavior
+		return nil
+	}
+
+	// Get SQL columns from the model
+	columns := reflection.GetSQLModelColumns(model)
+	if len(columns) == 0 {
+		// No columns found, return nil
+		return nil
+	}
+
+	// Build a map for fast lookup
+	columnMap := make(map[string]bool, len(columns))
+	for _, col := range columns {
+		columnMap[strings.ToLower(col)] = true
+	}
+
+	return columnMap
+}
+
+// extractTableAndColumn extracts the table prefix and column name from a qualified reference
+// For example: "users.status = 'active'" returns ("users", "status")
+// Returns empty strings if no table prefix is found
+func extractTableAndColumn(cond string) (table string, column string) {
+	// Common SQL operators to find the column reference
+	operators := []string{" = ", " != ", " <> ", " > ", " >= ", " < ", " <= ", " LIKE ", " like ", " IN ", " in ", " IS ", " is "}
+
+	var columnRef string
+
+	// Find the column reference (left side of the operator)
+	for _, op := range operators {
+		if idx := strings.Index(cond, op); idx > 0 {
+			columnRef = strings.TrimSpace(cond[:idx])
+			break
+		}
+	}
+
+	// If no operator found, the whole condition might be the column reference
+	if columnRef == "" {
+		parts := strings.Fields(cond)
+		if len(parts) > 0 {
+			columnRef = parts[0]
+		}
+	}
+
+	if columnRef == "" {
+		return "", ""
+	}
+
+	// Remove any quotes
+	columnRef = strings.Trim(columnRef, "`\"'")
+
+	// Check if it contains a dot (qualified reference)
+	if dotIdx := strings.LastIndex(columnRef, "."); dotIdx > 0 {
+		table = columnRef[:dotIdx]
+		column = columnRef[dotIdx+1:]
+
+		// Remove quotes from table and column if present
+		table = strings.Trim(table, "`\"'")
+		column = strings.Trim(column, "`\"'")
+
+		return table, column
+	}
+
+	return "", ""
+}
+
+// isValidColumn checks if a column name exists in the valid columns map
+// Handles case-insensitive comparison
+func isValidColumn(columnName string, validColumns map[string]bool) bool {
+	if validColumns == nil {
+		return true // No model info, assume valid
+	}
+	return validColumns[strings.ToLower(columnName)]
+}

pkg/common/sql_helpers_test.go

@@ -0,0 +1,412 @@
+package common
+
+import (
+	"testing"
+
+	"github.com/bitechdev/ResolveSpec/pkg/modelregistry"
+)
+
+func TestSanitizeWhereClause(t *testing.T) {
+	tests := []struct {
+		name      string
+		where     string
+		tableName string
+		expected  string
+	}{
+		{
+			name:      "trivial conditions in parentheses",
+			where:     "(true AND true AND true)",
+			tableName: "mastertask",
+			expected:  "",
+		},
+		{
+			name:      "trivial conditions without parentheses",
+			where:     "true AND true AND true",
+			tableName: "mastertask",
+			expected:  "",
+		},
+		{
+			name:      "single trivial condition",
+			where:     "true",
+			tableName: "mastertask",
+			expected:  "",
+		},
+		{
+			name:      "valid condition with parentheses - no prefix added",
+			where:     "(status = 'active')",
+			tableName: "users",
+			expected:  "status = 'active'",
+		},
+		{
+			name:      "mixed trivial and valid conditions - no prefix added",
+			where:     "true AND status = 'active' AND 1=1",
+			tableName: "users",
+			expected:  "status = 'active'",
+		},
+		{
+			name:      "condition with correct table prefix - unchanged",
+			where:     "users.status = 'active'",
+			tableName: "users",
+			expected:  "users.status = 'active'",
+		},
+		{
+			name:      "condition with incorrect table prefix - fixed",
+			where:     "wrong_table.status = 'active'",
+			tableName: "users",
+			expected:  "users.status = 'active'",
+		},
+		{
+			name:      "multiple conditions with incorrect prefix - fixed",
+			where:     "wrong_table.status = 'active' AND wrong_table.age > 18",
+			tableName: "users",
+			expected:  "users.status = 'active' AND users.age > 18",
+		},
+		{
+			name:      "multiple valid conditions without prefix - no prefix added",
+			where:     "status = 'active' AND age > 18",
+			tableName: "users",
+			expected:  "status = 'active' AND age > 18",
+		},
+		{
+			name:      "no table name provided",
+			where:     "status = 'active'",
+			tableName: "",
+			expected:  "status = 'active'",
+		},
+		{
+			name:      "empty where clause",
+			where:     "",
+			tableName: "users",
+			expected:  "",
+		},
+		{
+			name:      "mixed correct and incorrect prefixes",
+			where:     "users.status = 'active' AND wrong_table.age > 18",
+			tableName: "users",
+			expected:  "users.status = 'active' AND users.age > 18",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := SanitizeWhereClause(tt.where, tt.tableName)
+			if result != tt.expected {
+				t.Errorf("SanitizeWhereClause(%q, %q) = %q; want %q", tt.where, tt.tableName, result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestStripOuterParentheses(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "single level parentheses",
+			input:    "(true)",
+			expected: "true",
+		},
+		{
+			name:     "multiple levels",
+			input:    "((true))",
+			expected: "true",
+		},
+		{
+			name:     "no parentheses",
+			input:    "true",
+			expected: "true",
+		},
+		{
+			name:     "mismatched parentheses",
+			input:    "(true",
+			expected: "(true",
+		},
+		{
+			name:     "complex expression",
+			input:    "(a AND b)",
+			expected: "a AND b",
+		},
+		{
+			name:     "nested but not outer",
+			input:    "(a AND (b OR c)) AND d",
+			expected: "(a AND (b OR c)) AND d",
+		},
+		{
+			name:     "with spaces",
+			input:    "  ( true )  ",
+			expected: "true",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := stripOuterParentheses(tt.input)
+			if result != tt.expected {
+				t.Errorf("stripOuterParentheses(%q) = %q; want %q", tt.input, result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestIsTrivialCondition(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected bool
+	}{
+		{"true", "true", true},
+		{"true with spaces", "  true  ", true},
+		{"TRUE uppercase", "TRUE", true},
+		{"1=1", "1=1", true},
+		{"1 = 1", "1 = 1", true},
+		{"true = true", "true = true", true},
+		{"valid condition", "status = 'active'", false},
+		{"false", "false", false},
+		{"column name", "is_active", false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := IsTrivialCondition(tt.input)
+			if result != tt.expected {
+				t.Errorf("IsTrivialCondition(%q) = %v; want %v", tt.input, result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestExtractTableAndColumn(t *testing.T) {
+	tests := []struct {
+		name          string
+		input         string
+		expectedTable string
+		expectedCol   string
+	}{
+		{
+			name:          "qualified column with equals",
+			input:         "users.status = 'active'",
+			expectedTable: "users",
+			expectedCol:   "status",
+		},
+		{
+			name:          "qualified column with greater than",
+			input:         "users.age > 18",
+			expectedTable: "users",
+			expectedCol:   "age",
+		},
+		{
+			name:          "qualified column with LIKE",
+			input:         "users.name LIKE '%john%'",
+			expectedTable: "users",
+			expectedCol:   "name",
+		},
+		{
+			name:          "qualified column with IN",
+			input:         "users.status IN ('active', 'pending')",
+			expectedTable: "users",
+			expectedCol:   "status",
+		},
+		{
+			name:          "unqualified column",
+			input:         "status = 'active'",
+			expectedTable: "",
+			expectedCol:   "",
+		},
+		{
+			name:          "qualified with backticks",
+			input:         "`users`.`status` = 'active'",
+			expectedTable: "users",
+			expectedCol:   "status",
+		},
+		{
+			name:          "schema.table.column reference",
+			input:         "public.users.status = 'active'",
+			expectedTable: "public.users",
+			expectedCol:   "status",
+		},
+		{
+			name:          "empty string",
+			input:         "",
+			expectedTable: "",
+			expectedCol:   "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			table, col := extractTableAndColumn(tt.input)
+			if table != tt.expectedTable || col != tt.expectedCol {
+				t.Errorf("extractTableAndColumn(%q) = (%q, %q); want (%q, %q)",
+					tt.input, table, col, tt.expectedTable, tt.expectedCol)
+			}
+		})
+	}
+}
+
+func TestSanitizeWhereClauseWithPreloads(t *testing.T) {
+	tests := []struct {
+		name      string
+		where     string
+		tableName string
+		options   *RequestOptions
+		expected  string
+	}{
+		{
+			name:      "preload relation prefix is preserved",
+			where:     "Department.name = 'Engineering'",
+			tableName: "users",
+			options: &RequestOptions{
+				Preload: []PreloadOption{
+					{Relation: "Department"},
+				},
+			},
+			expected: "Department.name = 'Engineering'",
+		},
+		{
+			name:      "multiple preload relations - all preserved",
+			where:     "Department.name = 'Engineering' AND Manager.status = 'active'",
+			tableName: "users",
+			options: &RequestOptions{
+				Preload: []PreloadOption{
+					{Relation: "Department"},
+					{Relation: "Manager"},
+				},
+			},
+			expected: "Department.name = 'Engineering' AND Manager.status = 'active'",
+		},
+		{
+			name:      "mix of main table and preload relation",
+			where:     "users.status = 'active' AND Department.name = 'Engineering'",
+			tableName: "users",
+			options: &RequestOptions{
+				Preload: []PreloadOption{
+					{Relation: "Department"},
+				},
+			},
+			expected: "users.status = 'active' AND Department.name = 'Engineering'",
+		},
+		{
+			name:      "incorrect prefix fixed when not a preload relation",
+			where:     "wrong_table.status = 'active' AND Department.name = 'Engineering'",
+			tableName: "users",
+			options: &RequestOptions{
+				Preload: []PreloadOption{
+					{Relation: "Department"},
+				},
+			},
+			expected: "users.status = 'active' AND Department.name = 'Engineering'",
+		},
+		{
+			name:      "no options provided - works as before",
+			where:     "wrong_table.status = 'active'",
+			tableName: "users",
+			options:   nil,
+			expected:  "users.status = 'active'",
+		},
+		{
+			name:      "empty preload list - works as before",
+			where:     "wrong_table.status = 'active'",
+			tableName: "users",
+			options:   &RequestOptions{Preload: []PreloadOption{}},
+			expected:  "users.status = 'active'",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var result string
+			if tt.options != nil {
+				result = SanitizeWhereClause(tt.where, tt.tableName, tt.options)
+			} else {
+				result = SanitizeWhereClause(tt.where, tt.tableName)
+			}
+			if result != tt.expected {
+				t.Errorf("SanitizeWhereClause(%q, %q, options) = %q; want %q", tt.where, tt.tableName, result, tt.expected)
+			}
+		})
+	}
+}
+
+// Test model for model-aware sanitization tests
+type MasterTask struct {
+	ID     int    `bun:"id,pk"`
+	Name   string `bun:"name"`
+	Status string `bun:"status"`
+	UserID int    `bun:"user_id"`
+}
+
+func TestSanitizeWhereClauseWithModel(t *testing.T) {
+	// Register the test model
+	err := modelregistry.RegisterModel(MasterTask{}, "mastertask")
+	if err != nil {
+		// Model might already be registered, ignore error
+		t.Logf("Model registration returned: %v", err)
+	}
+
+	tests := []struct {
+		name      string
+		where     string
+		tableName string
+		expected  string
+	}{
+		{
+			name:      "valid column without prefix - no prefix added",
+			where:     "status = 'active'",
+			tableName: "mastertask",
+			expected:  "status = 'active'",
+		},
+		{
+			name:      "multiple valid columns without prefix - no prefix added",
+			where:     "status = 'active' AND user_id = 123",
+			tableName: "mastertask",
+			expected:  "status = 'active' AND user_id = 123",
+		},
+		{
+			name:      "incorrect table prefix on valid column - fixed",
+			where:     "wrong_table.status = 'active'",
+			tableName: "mastertask",
+			expected:  "mastertask.status = 'active'",
+		},
+		{
+			name:      "incorrect prefix on invalid column - not fixed",
+			where:     "wrong_table.invalid_column = 'value'",
+			tableName: "mastertask",
+			expected:  "wrong_table.invalid_column = 'value'",
+		},
+		{
+			name:      "mix of valid and trivial conditions",
+			where:     "true AND status = 'active' AND 1=1",
+			tableName: "mastertask",
+			expected:  "status = 'active'",
+		},
+		{
+			name:      "parentheses with valid column - no prefix added",
+			where:     "(status = 'active')",
+			tableName: "mastertask",
+			expected:  "status = 'active'",
+		},
+		{
+			name:      "correct prefix - unchanged",
+			where:     "mastertask.status = 'active'",
+			tableName: "mastertask",
+			expected:  "mastertask.status = 'active'",
+		},
+		{
+			name:      "multiple conditions with mixed prefixes",
+			where:     "mastertask.status = 'active' AND wrong_table.user_id = 123",
+			tableName: "mastertask",
+			expected:  "mastertask.status = 'active' AND mastertask.user_id = 123",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := SanitizeWhereClause(tt.where, tt.tableName)
+			if result != tt.expected {
+				t.Errorf("SanitizeWhereClause(%q, %q) = %q; want %q", tt.where, tt.tableName, result, tt.expected)
+			}
+		})
+	}
+}

pkg/common/sql_types_test.go

@@ -9,18 +9,18 @@ import (
 	"github.com/google/uuid"
 )
 
-// TestSqlInt16 tests SqlInt16 type
-func TestSqlInt16(t *testing.T) {
+// TestNewSqlInt16 tests NewSqlInt16 type
+func TestNewSqlInt16(t *testing.T) {
 	tests := []struct {
 		name     string
 		input    interface{}
 		expected SqlInt16
 	}{
-		{"int", 42, SqlInt16(42)},
-		{"int32", int32(100), SqlInt16(100)},
-		{"int64", int64(200), SqlInt16(200)},
-		{"string", "123", SqlInt16(123)},
-		{"nil", nil, SqlInt16(0)},
+		{"int", 42, Null(int16(42), true)},
+		{"int32", int32(100), NewSqlInt16(100)},
+		{"int64", int64(200), NewSqlInt16(200)},
+		{"string", "123", NewSqlInt16(123)},
+		{"nil", nil, Null(int16(0), false)},
 	}
 
 	for _, tt := range tests {
@@ -36,15 +36,15 @@ func TestSqlInt16(t *testing.T) {
 	}
 }
 
-func TestSqlInt16_Value(t *testing.T) {
+func TestNewSqlInt16_Value(t *testing.T) {
 	tests := []struct {
 		name     string
 		input    SqlInt16
 		expected driver.Value
 	}{
-		{"zero", SqlInt16(0), nil},
-		{"positive", SqlInt16(42), int64(42)},
-		{"negative", SqlInt16(-10), int64(-10)},
+		{"zero", Null(int16(0), false), nil},
+		{"positive", NewSqlInt16(42), int16(42)},
+		{"negative", NewSqlInt16(-10), int16(-10)},
 	}
 
 	for _, tt := range tests {
@@ -60,8 +60,8 @@ func TestSqlInt16_Value(t *testing.T) {
 	}
 }
 
-func TestSqlInt16_JSON(t *testing.T) {
-	n := SqlInt16(42)
+func TestNewSqlInt16_JSON(t *testing.T) {
+	n := NewSqlInt16(42)
 
 	// Marshal
 	data, err := json.Marshal(n)
@@ -78,24 +78,24 @@ func TestSqlInt16_JSON(t *testing.T) {
 	if err := json.Unmarshal([]byte("123"), &n2); err != nil {
 		t.Fatalf("Unmarshal failed: %v", err)
 	}
-	if n2 != 123 {
-		t.Errorf("expected 123, got %d", n2)
+	if n2.Int64() != 123 {
+		t.Errorf("expected 123, got %d", n2.Int64())
 	}
 }
 
-// TestSqlInt64 tests SqlInt64 type
-func TestSqlInt64(t *testing.T) {
+// TestNewSqlInt64 tests NewSqlInt64 type
+func TestNewSqlInt64(t *testing.T) {
 	tests := []struct {
 		name     string
 		input    interface{}
 		expected SqlInt64
 	}{
-		{"int", 42, SqlInt64(42)},
-		{"int32", int32(100), SqlInt64(100)},
-		{"int64", int64(9223372036854775807), SqlInt64(9223372036854775807)},
-		{"uint32", uint32(100), SqlInt64(100)},
-		{"uint64", uint64(200), SqlInt64(200)},
-		{"nil", nil, SqlInt64(0)},
+		{"int", 42, NewSqlInt64(42)},
+		{"int32", int32(100), NewSqlInt64(100)},
+		{"int64", int64(9223372036854775807), NewSqlInt64(9223372036854775807)},
+		{"uint32", uint32(100), NewSqlInt64(100)},
+		{"uint64", uint64(200), NewSqlInt64(200)},
+		{"nil", nil, SqlInt64{}},
 	}
 
 	for _, tt := range tests {
@@ -135,8 +135,8 @@ func TestSqlFloat64(t *testing.T) {
 			if n.Valid != tt.valid {
 				t.Errorf("expected valid=%v, got valid=%v", tt.valid, n.Valid)
 			}
-			if tt.valid && n.Float64 != tt.expected {
-				t.Errorf("expected %v, got %v", tt.expected, n.Float64)
+			if tt.valid && n.Float64() != tt.expected {
+				t.Errorf("expected %v, got %v", tt.expected, n.Float64())
 			}
 		})
 	}
@@ -162,7 +162,7 @@ func TestSqlTimeStamp(t *testing.T) {
 			if err := ts.Scan(tt.input); err != nil {
 				t.Fatalf("Scan failed: %v", err)
 			}
-			if ts.GetTime().IsZero() {
+			if ts.Time().IsZero() {
 				t.Error("expected non-zero time")
 			}
 		})
@@ -171,7 +171,7 @@ func TestSqlTimeStamp(t *testing.T) {
 
 func TestSqlTimeStamp_JSON(t *testing.T) {
 	now := time.Date(2024, 1, 15, 10, 30, 45, 0, time.UTC)
-	ts := SqlTimeStamp(now)
+	ts := NewSqlTimeStamp(now)
 
 	// Marshal
 	data, err := json.Marshal(ts)
@@ -188,8 +188,8 @@ func TestSqlTimeStamp_JSON(t *testing.T) {
 	if err := json.Unmarshal([]byte(`"2024-01-15T10:30:45"`), &ts2); err != nil {
 		t.Fatalf("Unmarshal failed: %v", err)
 	}
-	if ts2.GetTime().Year() != 2024 {
-		t.Errorf("expected year 2024, got %d", ts2.GetTime().Year())
+	if ts2.Time().Year() != 2024 {
+		t.Errorf("expected year 2024, got %d", ts2.Time().Year())
 	}
 
 	// Test null
@@ -226,7 +226,7 @@ func TestSqlDate(t *testing.T) {
 }
 
 func TestSqlDate_JSON(t *testing.T) {
-	date := SqlDate(time.Date(2024, 1, 15, 0, 0, 0, 0, time.UTC))
+	date := NewSqlDate(time.Date(2024, 1, 15, 0, 0, 0, 0, time.UTC))
 
 	// Marshal
 	data, err := json.Marshal(date)
@@ -471,8 +471,8 @@ func TestSqlUUID_Scan(t *testing.T) {
 			if u.Valid != tt.valid {
 				t.Errorf("expected valid=%v, got valid=%v", tt.valid, u.Valid)
 			}
-			if tt.valid && u.String != tt.expected {
-				t.Errorf("expected %s, got %s", tt.expected, u.String)
+			if tt.valid && u.String() != tt.expected {
+				t.Errorf("expected %s, got %s", tt.expected, u.String())
 			}
 		})
 	}
@@ -480,13 +480,13 @@ func TestSqlUUID_Scan(t *testing.T) {
 
 func TestSqlUUID_Value(t *testing.T) {
 	testUUID := uuid.New()
-	u := SqlUUID{String: testUUID.String(), Valid: true}
+	u := NewSqlUUID(testUUID)
 
 	val, err := u.Value()
 	if err != nil {
 		t.Fatalf("Value failed: %v", err)
 	}
-	if val != testUUID.String() {
+	if val != testUUID {
 		t.Errorf("expected %s, got %s", testUUID.String(), val)
 	}
 
@@ -503,7 +503,7 @@ func TestSqlUUID_Value(t *testing.T) {
 
 func TestSqlUUID_JSON(t *testing.T) {
 	testUUID := uuid.New()
-	u := SqlUUID{String: testUUID.String(), Valid: true}
+	u := NewSqlUUID(testUUID)
 
 	// Marshal
 	data, err := json.Marshal(u)
@@ -520,8 +520,8 @@ func TestSqlUUID_JSON(t *testing.T) {
 	if err := json.Unmarshal([]byte(`"`+testUUID.String()+`"`), &u2); err != nil {
 		t.Fatalf("Unmarshal failed: %v", err)
 	}
-	if u2.String != testUUID.String() {
-		t.Errorf("expected %s, got %s", testUUID.String(), u2.String)
+	if u2.String() != testUUID.String() {
+		t.Errorf("expected %s, got %s", testUUID.String(), u2.String())
 	}
 
 	// Test null

pkg/common/types.go

@@ -32,15 +32,22 @@ type Parameter struct {
 }
 
 type PreloadOption struct {
-	Relation    string         `json:"relation"`
-	Columns     []string       `json:"columns"`
-	OmitColumns []string       `json:"omit_columns"`
-	Sort        []SortOption   `json:"sort"`
-	Filters     []FilterOption `json:"filters"`
-	Where       string         `json:"where"`
-	Limit       *int           `json:"limit"`
-	Offset      *int           `json:"offset"`
-	Updatable   *bool          `json:"updateable"` // if true, the relation can be updated
+	Relation    string            `json:"relation"`
+	Columns     []string          `json:"columns"`
+	OmitColumns []string          `json:"omit_columns"`
+	Sort        []SortOption      `json:"sort"`
+	Filters     []FilterOption    `json:"filters"`
+	Where       string            `json:"where"`
+	Limit       *int              `json:"limit"`
+	Offset      *int              `json:"offset"`
+	Updatable   *bool             `json:"updateable"`  // if true, the relation can be updated
+	ComputedQL  map[string]string `json:"computed_ql"` // Computed columns as SQL expressions
+	Recursive   bool              `json:"recursive"`   // if true, preload recursively up to 5 levels
+
+	// Relationship keys from XFiles - used to build proper foreign key filters
+	PrimaryKey string `json:"primary_key"` // Primary key of the related table
+	RelatedKey string `json:"related_key"` // For child tables: column in child that references parent
+	ForeignKey string `json:"foreign_key"` // For parent tables: column in current table that references parent
 }
 
 type FilterOption struct {

pkg/common/validation.go

@@ -6,6 +6,7 @@ import (
 	"strings"
 
 	"github.com/bitechdev/ResolveSpec/pkg/logger"
+	"github.com/bitechdev/ResolveSpec/pkg/reflection"
 )
 
 // ColumnValidator validates column names against a model's fields
@@ -95,6 +96,7 @@ func (v *ColumnValidator) getColumnName(field reflect.StructField) string {
 // ValidateColumn validates a single column name
 // Returns nil if valid, error if invalid
 // Columns prefixed with "cql" (case insensitive) are always valid
+// Handles PostgreSQL JSON operators (-> and ->>)
 func (v *ColumnValidator) ValidateColumn(column string) error {
 	// Allow empty columns
 	if column == "" {
@@ -106,8 +108,11 @@ func (v *ColumnValidator) ValidateColumn(column string) error {
 		return nil
 	}
 
+	// Extract source column name (remove JSON operators like ->> or ->)
+	sourceColumn := reflection.ExtractSourceColumn(column)
+
 	// Check if column exists in model
-	if _, exists := v.validColumns[strings.ToLower(column)]; !exists {
+	if _, exists := v.validColumns[strings.ToLower(sourceColumn)]; !exists {
 		return fmt.Errorf("invalid column '%s': column does not exist in model", column)
 	}
 

pkg/common/validation_json_test.go

@@ -0,0 +1,126 @@
+package common
+
+import (
+	"testing"
+
+	"github.com/bitechdev/ResolveSpec/pkg/reflection"
+)
+
+func TestExtractSourceColumn(t *testing.T) {
+	testCases := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "simple column name",
+			input:    "columna",
+			expected: "columna",
+		},
+		{
+			name:     "column with ->> operator",
+			input:    "columna->>'val'",
+			expected: "columna",
+		},
+		{
+			name:     "column with -> operator",
+			input:    "columna->'key'",
+			expected: "columna",
+		},
+		{
+			name:     "column with table prefix and ->> operator",
+			input:    "table.columna->>'val'",
+			expected: "table.columna",
+		},
+		{
+			name:     "column with table prefix and -> operator",
+			input:    "table.columna->'key'",
+			expected: "table.columna",
+		},
+		{
+			name:     "complex JSON path with ->>",
+			input:    "data->>'nested'->>'value'",
+			expected: "data",
+		},
+		{
+			name:     "column with spaces before operator",
+			input:    "columna ->>'val'",
+			expected: "columna",
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			result := reflection.ExtractSourceColumn(tc.input)
+			if result != tc.expected {
+				t.Errorf("reflection.ExtractSourceColumn(%q) = %q; want %q", tc.input, result, tc.expected)
+			}
+		})
+	}
+}
+
+func TestValidateColumnWithJSONOperators(t *testing.T) {
+	// Create a test model
+	type TestModel struct {
+		ID       int    `json:"id"`
+		Name     string `json:"name"`
+		Data     string `json:"data"` // JSON column
+		Metadata string `json:"metadata"`
+	}
+
+	validator := NewColumnValidator(TestModel{})
+
+	testCases := []struct {
+		name      string
+		column    string
+		shouldErr bool
+	}{
+		{
+			name:      "simple valid column",
+			column:    "name",
+			shouldErr: false,
+		},
+		{
+			name:      "valid column with ->> operator",
+			column:    "data->>'field'",
+			shouldErr: false,
+		},
+		{
+			name:      "valid column with -> operator",
+			column:    "metadata->'key'",
+			shouldErr: false,
+		},
+		{
+			name:      "invalid column",
+			column:    "invalid_column",
+			shouldErr: true,
+		},
+		{
+			name:      "invalid column with ->> operator",
+			column:    "invalid_column->>'field'",
+			shouldErr: true,
+		},
+		{
+			name:      "cql prefixed column (always valid)",
+			column:    "cql_computed",
+			shouldErr: false,
+		},
+		{
+			name:      "empty column",
+			column:    "",
+			shouldErr: false,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			err := validator.ValidateColumn(tc.column)
+			if tc.shouldErr && err == nil {
+				t.Errorf("ValidateColumn(%q) expected error, got nil", tc.column)
+			}
+			if !tc.shouldErr && err != nil {
+				t.Errorf("ValidateColumn(%q) expected no error, got %v", tc.column, err)
+			}
+		})
+	}
+}

pkg/config/README.md

@@ -0,0 +1,291 @@
+# ResolveSpec Configuration System
+
+A centralized configuration system with support for multiple configuration sources: config files (YAML, TOML, JSON), environment variables, and programmatic configuration.
+
+## Features
+
+- **Multiple Config Sources**: Config files, environment variables, and code
+- **Priority Order**: Environment variables > Config file > Defaults
+- **Multiple Formats**: YAML, TOML, JSON supported
+- **Type Safety**: Strongly-typed configuration structs
+- **Sensible Defaults**: Works out of the box with reasonable defaults
+
+## Quick Start
+
+### Basic Usage
+
+```go
+import "github.com/heinhel/ResolveSpec/pkg/config"
+
+// Create a new config manager
+mgr := config.NewManager()
+
+// Load configuration from file and environment
+if err := mgr.Load(); err != nil {
+    log.Fatal(err)
+}
+
+// Get the complete configuration
+cfg, err := mgr.GetConfig()
+if err != nil {
+    log.Fatal(err)
+}
+
+// Use the configuration
+fmt.Println("Server address:", cfg.Server.Addr)
+```
+
+### Custom Configuration Paths
+
+```go
+mgr := config.NewManagerWithOptions(
+    config.WithConfigFile("/path/to/config.yaml"),
+    config.WithEnvPrefix("MYAPP"),
+)
+```
+
+## Configuration Sources
+
+### 1. Config Files
+
+Place a `config.yaml` file in one of these locations:
+- Current directory (`.`)
+- `./config/`
+- `/etc/resolvespec/`
+- `$HOME/.resolvespec/`
+
+Example `config.yaml`:
+
+```yaml
+server:
+  addr: ":8080"
+  shutdown_timeout: 30s
+
+tracing:
+  enabled: true
+  service_name: "my-service"
+
+cache:
+  provider: "redis"
+  redis:
+    host: "localhost"
+    port: 6379
+```
+
+### 2. Environment Variables
+
+All configuration can be set via environment variables with the `RESOLVESPEC_` prefix:
+
+```bash
+export RESOLVESPEC_SERVER_ADDR=":9090"
+export RESOLVESPEC_TRACING_ENABLED=true
+export RESOLVESPEC_CACHE_PROVIDER=redis
+export RESOLVESPEC_CACHE_REDIS_HOST=localhost
+```
+
+Nested configuration uses underscores:
+- `server.addr` → `RESOLVESPEC_SERVER_ADDR`
+- `cache.redis.host` → `RESOLVESPEC_CACHE_REDIS_HOST`
+
+### 3. Programmatic Configuration
+
+```go
+mgr := config.NewManager()
+mgr.Set("server.addr", ":9090")
+mgr.Set("tracing.enabled", true)
+
+cfg, _ := mgr.GetConfig()
+```
+
+## Configuration Options
+
+### Server Configuration
+
+```yaml
+server:
+  addr: ":8080"              # Server address
+  shutdown_timeout: 30s       # Graceful shutdown timeout
+  drain_timeout: 25s          # Connection drain timeout
+  read_timeout: 10s           # HTTP read timeout
+  write_timeout: 10s          # HTTP write timeout
+  idle_timeout: 120s          # HTTP idle timeout
+```
+
+### Tracing Configuration
+
+```yaml
+tracing:
+  enabled: false                                  # Enable/disable tracing
+  service_name: "resolvespec"                     # Service name
+  service_version: "1.0.0"                        # Service version
+  endpoint: "http://localhost:4318/v1/traces"     # OTLP endpoint
+```
+
+### Cache Configuration
+
+```yaml
+cache:
+  provider: "memory"  # Options: memory, redis, memcache
+
+  redis:
+    host: "localhost"
+    port: 6379
+    password: ""
+    db: 0
+
+  memcache:
+    servers:
+      - "localhost:11211"
+    max_idle_conns: 10
+    timeout: 100ms
+```
+
+### Logger Configuration
+
+```yaml
+logger:
+  dev: false    # Development mode (human-readable output)
+  path: ""      # Log file path (empty = stdout)
+```
+
+### Middleware Configuration
+
+```yaml
+middleware:
+  rate_limit_rps: 100.0       # Requests per second
+  rate_limit_burst: 200        # Burst size
+  max_request_size: 10485760   # Max request size in bytes (10MB)
+```
+
+### CORS Configuration
+
+```yaml
+cors:
+  allowed_origins:
+    - "*"
+  allowed_methods:
+    - "GET"
+    - "POST"
+    - "PUT"
+    - "DELETE"
+    - "OPTIONS"
+  allowed_headers:
+    - "*"
+  max_age: 3600
+```
+
+### Database Configuration
+
+```yaml
+database:
+  url: "host=localhost user=postgres password=postgres dbname=mydb port=5432 sslmode=disable"
+```
+
+## Priority and Overrides
+
+Configuration sources are applied in this order (highest priority first):
+
+1. **Environment Variables** (highest priority)
+2. **Config File**
+3. **Defaults** (lowest priority)
+
+This allows you to:
+- Set defaults in code
+- Override with a config file
+- Override specific values with environment variables
+
+## Examples
+
+### Production Setup
+
+```yaml
+# config.yaml
+server:
+  addr: ":8080"
+
+tracing:
+  enabled: true
+  service_name: "myapi"
+  endpoint: "http://jaeger:4318/v1/traces"
+
+cache:
+  provider: "redis"
+  redis:
+    host: "redis"
+    port: 6379
+    password: "${REDIS_PASSWORD}"
+
+logger:
+  dev: false
+  path: "/var/log/myapi/app.log"
+```
+
+### Development Setup
+
+```bash
+# Use environment variables for development
+export RESOLVESPEC_LOGGER_DEV=true
+export RESOLVESPEC_TRACING_ENABLED=false
+export RESOLVESPEC_CACHE_PROVIDER=memory
+```
+
+### Testing Setup
+
+```go
+// Override config for tests
+mgr := config.NewManager()
+mgr.Set("cache.provider", "memory")
+mgr.Set("database.url", testDBURL)
+
+cfg, _ := mgr.GetConfig()
+```
+
+## Best Practices
+
+1. **Use config files for base configuration** - Define your standard settings
+2. **Use environment variables for secrets** - Never commit passwords/tokens
+3. **Use environment variables for deployment-specific values** - Different per environment
+4. **Keep defaults sensible** - Application should work with minimal configuration
+5. **Document your configuration** - Comment your config.yaml files
+
+## Integration with ResolveSpec Components
+
+The configuration system integrates seamlessly with ResolveSpec components:
+
+```go
+cfg, _ := config.NewManager().Load().GetConfig()
+
+// Server
+srv := server.NewGracefulServer(server.Config{
+    Addr:            cfg.Server.Addr,
+    ShutdownTimeout: cfg.Server.ShutdownTimeout,
+    // ... other fields
+})
+
+// Tracing
+if cfg.Tracing.Enabled {
+    tracer := tracing.Init(tracing.Config{
+        ServiceName:    cfg.Tracing.ServiceName,
+        ServiceVersion: cfg.Tracing.ServiceVersion,
+        Endpoint:       cfg.Tracing.Endpoint,
+    })
+    defer tracer.Shutdown(context.Background())
+}
+
+// Cache
+var cacheProvider cache.Provider
+switch cfg.Cache.Provider {
+case "redis":
+    cacheProvider = cache.NewRedisProvider(cfg.Cache.Redis.Host, cfg.Cache.Redis.Port, ...)
+case "memcache":
+    cacheProvider = cache.NewMemcacheProvider(cfg.Cache.Memcache.Servers, ...)
+default:
+    cacheProvider = cache.NewMemoryProvider()
+}
+
+// Logger
+logger.Init(cfg.Logger.Dev)
+if cfg.Logger.Path != "" {
+    logger.UpdateLoggerPath(cfg.Logger.Path, cfg.Logger.Dev)
+}
+```

pkg/config/config.go

@@ -0,0 +1,80 @@
+package config
+
+import "time"
+
+// Config represents the complete application configuration
+type Config struct {
+	Server     ServerConfig     `mapstructure:"server"`
+	Tracing    TracingConfig    `mapstructure:"tracing"`
+	Cache      CacheConfig      `mapstructure:"cache"`
+	Logger     LoggerConfig     `mapstructure:"logger"`
+	Middleware MiddlewareConfig `mapstructure:"middleware"`
+	CORS       CORSConfig       `mapstructure:"cors"`
+	Database   DatabaseConfig   `mapstructure:"database"`
+}
+
+// ServerConfig holds server-related configuration
+type ServerConfig struct {
+	Addr            string        `mapstructure:"addr"`
+	ShutdownTimeout time.Duration `mapstructure:"shutdown_timeout"`
+	DrainTimeout    time.Duration `mapstructure:"drain_timeout"`
+	ReadTimeout     time.Duration `mapstructure:"read_timeout"`
+	WriteTimeout    time.Duration `mapstructure:"write_timeout"`
+	IdleTimeout     time.Duration `mapstructure:"idle_timeout"`
+}
+
+// TracingConfig holds OpenTelemetry tracing configuration
+type TracingConfig struct {
+	Enabled        bool   `mapstructure:"enabled"`
+	ServiceName    string `mapstructure:"service_name"`
+	ServiceVersion string `mapstructure:"service_version"`
+	Endpoint       string `mapstructure:"endpoint"`
+}
+
+// CacheConfig holds cache provider configuration
+type CacheConfig struct {
+	Provider string         `mapstructure:"provider"` // memory, redis, memcache
+	Redis    RedisConfig    `mapstructure:"redis"`
+	Memcache MemcacheConfig `mapstructure:"memcache"`
+}
+
+// RedisConfig holds Redis-specific configuration
+type RedisConfig struct {
+	Host     string `mapstructure:"host"`
+	Port     int    `mapstructure:"port"`
+	Password string `mapstructure:"password"`
+	DB       int    `mapstructure:"db"`
+}
+
+// MemcacheConfig holds Memcache-specific configuration
+type MemcacheConfig struct {
+	Servers      []string      `mapstructure:"servers"`
+	MaxIdleConns int           `mapstructure:"max_idle_conns"`
+	Timeout      time.Duration `mapstructure:"timeout"`
+}
+
+// LoggerConfig holds logger configuration
+type LoggerConfig struct {
+	Dev  bool   `mapstructure:"dev"`
+	Path string `mapstructure:"path"`
+}
+
+// MiddlewareConfig holds middleware configuration
+type MiddlewareConfig struct {
+	RateLimitRPS   float64 `mapstructure:"rate_limit_rps"`
+	RateLimitBurst int     `mapstructure:"rate_limit_burst"`
+	MaxRequestSize int64   `mapstructure:"max_request_size"`
+}
+
+// CORSConfig holds CORS configuration
+type CORSConfig struct {
+	AllowedOrigins []string `mapstructure:"allowed_origins"`
+	AllowedMethods []string `mapstructure:"allowed_methods"`
+	AllowedHeaders []string `mapstructure:"allowed_headers"`
+	MaxAge         int      `mapstructure:"max_age"`
+}
+
+// DatabaseConfig holds database configuration (primarily for testing)
+type DatabaseConfig struct {
+	URL string `mapstructure:"url"`
+}

pkg/config/manager.go

@@ -0,0 +1,168 @@
+package config
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/spf13/viper"
+)
+
+// Manager handles configuration loading from multiple sources
+type Manager struct {
+	v *viper.Viper
+}
+
+// NewManager creates a new configuration manager with defaults
+func NewManager() *Manager {
+	v := viper.New()
+
+	// Set configuration file settings
+	v.SetConfigName("config")
+	v.SetConfigType("yaml")
+	v.AddConfigPath(".")
+	v.AddConfigPath("./config")
+	v.AddConfigPath("/etc/resolvespec")
+	v.AddConfigPath("$HOME/.resolvespec")
+
+	// Enable environment variable support
+	v.SetEnvPrefix("RESOLVESPEC")
+	v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
+	v.AutomaticEnv()
+
+	// Set default values
+	setDefaults(v)
+
+	return &Manager{v: v}
+}
+
+// NewManagerWithOptions creates a new configuration manager with custom options
+func NewManagerWithOptions(opts ...Option) *Manager {
+	m := NewManager()
+	for _, opt := range opts {
+		opt(m)
+	}
+	return m
+}
+
+// Option is a functional option for configuring the Manager
+type Option func(*Manager)
+
+// WithConfigFile sets a specific config file path
+func WithConfigFile(path string) Option {
+	return func(m *Manager) {
+		m.v.SetConfigFile(path)
+	}
+}
+
+// WithConfigName sets the config file name (without extension)
+func WithConfigName(name string) Option {
+	return func(m *Manager) {
+		m.v.SetConfigName(name)
+	}
+}
+
+// WithConfigPath adds a path to search for config files
+func WithConfigPath(path string) Option {
+	return func(m *Manager) {
+		m.v.AddConfigPath(path)
+	}
+}
+
+// WithEnvPrefix sets the environment variable prefix
+func WithEnvPrefix(prefix string) Option {
+	return func(m *Manager) {
+		m.v.SetEnvPrefix(prefix)
+	}
+}
+
+// Load attempts to load configuration from file and environment
+func (m *Manager) Load() error {
+	// Try to read config file (not an error if it doesn't exist)
+	if err := m.v.ReadInConfig(); err != nil {
+		if _, ok := err.(viper.ConfigFileNotFoundError); !ok {
+			return fmt.Errorf("error reading config file: %w", err)
+		}
+		// Config file not found; will rely on defaults and env vars
+	}
+
+	return nil
+}
+
+// GetConfig returns the complete configuration
+func (m *Manager) GetConfig() (*Config, error) {
+	var cfg Config
+	if err := m.v.Unmarshal(&cfg); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal config: %w", err)
+	}
+	return &cfg, nil
+}
+
+// Get returns a configuration value by key
+func (m *Manager) Get(key string) interface{} {
+	return m.v.Get(key)
+}
+
+// GetString returns a string configuration value
+func (m *Manager) GetString(key string) string {
+	return m.v.GetString(key)
+}
+
+// GetInt returns an int configuration value
+func (m *Manager) GetInt(key string) int {
+	return m.v.GetInt(key)
+}
+
+// GetBool returns a bool configuration value
+func (m *Manager) GetBool(key string) bool {
+	return m.v.GetBool(key)
+}
+
+// Set sets a configuration value
+func (m *Manager) Set(key string, value interface{}) {
+	m.v.Set(key, value)
+}
+
+// setDefaults sets default configuration values
+func setDefaults(v *viper.Viper) {
+	// Server defaults
+	v.SetDefault("server.addr", ":8080")
+	v.SetDefault("server.shutdown_timeout", "30s")
+	v.SetDefault("server.drain_timeout", "25s")
+	v.SetDefault("server.read_timeout", "10s")
+	v.SetDefault("server.write_timeout", "10s")
+	v.SetDefault("server.idle_timeout", "120s")
+
+	// Tracing defaults
+	v.SetDefault("tracing.enabled", false)
+	v.SetDefault("tracing.service_name", "resolvespec")
+	v.SetDefault("tracing.service_version", "1.0.0")
+	v.SetDefault("tracing.endpoint", "")
+
+	// Cache defaults
+	v.SetDefault("cache.provider", "memory")
+	v.SetDefault("cache.redis.host", "localhost")
+	v.SetDefault("cache.redis.port", 6379)
+	v.SetDefault("cache.redis.password", "")
+	v.SetDefault("cache.redis.db", 0)
+	v.SetDefault("cache.memcache.servers", []string{"localhost:11211"})
+	v.SetDefault("cache.memcache.max_idle_conns", 10)
+	v.SetDefault("cache.memcache.timeout", "100ms")
+
+	// Logger defaults
+	v.SetDefault("logger.dev", false)
+	v.SetDefault("logger.path", "")
+
+	// Middleware defaults
+	v.SetDefault("middleware.rate_limit_rps", 100.0)
+	v.SetDefault("middleware.rate_limit_burst", 200)
+	v.SetDefault("middleware.max_request_size", 10485760) // 10MB
+
+	// CORS defaults
+	v.SetDefault("cors.allowed_origins", []string{"*"})
+	v.SetDefault("cors.allowed_methods", []string{"GET", "POST", "PUT", "DELETE", "OPTIONS"})
+	v.SetDefault("cors.allowed_headers", []string{"*"})
+	v.SetDefault("cors.max_age", 3600)
+
+	// Database defaults
+	v.SetDefault("database.url", "")
+}

pkg/config/manager_test.go

@@ -0,0 +1,166 @@
+package config
+
+import (
+	"os"
+	"testing"
+	"time"
+)
+
+func TestNewManager(t *testing.T) {
+	mgr := NewManager()
+	if mgr == nil {
+		t.Fatal("Expected manager to be non-nil")
+	}
+
+	if mgr.v == nil {
+		t.Fatal("Expected viper instance to be non-nil")
+	}
+}
+
+func TestDefaultValues(t *testing.T) {
+	mgr := NewManager()
+	if err := mgr.Load(); err != nil {
+		t.Fatalf("Failed to load config: %v", err)
+	}
+
+	cfg, err := mgr.GetConfig()
+	if err != nil {
+		t.Fatalf("Failed to get config: %v", err)
+	}
+
+	// Test default values
+	tests := []struct {
+		name     string
+		got      interface{}
+		expected interface{}
+	}{
+		{"server.addr", cfg.Server.Addr, ":8080"},
+		{"server.shutdown_timeout", cfg.Server.ShutdownTimeout, 30 * time.Second},
+		{"tracing.enabled", cfg.Tracing.Enabled, false},
+		{"tracing.service_name", cfg.Tracing.ServiceName, "resolvespec"},
+		{"cache.provider", cfg.Cache.Provider, "memory"},
+		{"cache.redis.host", cfg.Cache.Redis.Host, "localhost"},
+		{"cache.redis.port", cfg.Cache.Redis.Port, 6379},
+		{"logger.dev", cfg.Logger.Dev, false},
+		{"middleware.rate_limit_rps", cfg.Middleware.RateLimitRPS, 100.0},
+		{"middleware.rate_limit_burst", cfg.Middleware.RateLimitBurst, 200},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if tt.got != tt.expected {
+				t.Errorf("%s: got %v, want %v", tt.name, tt.got, tt.expected)
+			}
+		})
+	}
+}
+
+func TestEnvironmentVariableOverrides(t *testing.T) {
+	// Set environment variables
+	os.Setenv("RESOLVESPEC_SERVER_ADDR", ":9090")
+	os.Setenv("RESOLVESPEC_TRACING_ENABLED", "true")
+	os.Setenv("RESOLVESPEC_CACHE_PROVIDER", "redis")
+	os.Setenv("RESOLVESPEC_LOGGER_DEV", "true")
+	defer func() {
+		os.Unsetenv("RESOLVESPEC_SERVER_ADDR")
+		os.Unsetenv("RESOLVESPEC_TRACING_ENABLED")
+		os.Unsetenv("RESOLVESPEC_CACHE_PROVIDER")
+		os.Unsetenv("RESOLVESPEC_LOGGER_DEV")
+	}()
+
+	mgr := NewManager()
+	if err := mgr.Load(); err != nil {
+		t.Fatalf("Failed to load config: %v", err)
+	}
+
+	cfg, err := mgr.GetConfig()
+	if err != nil {
+		t.Fatalf("Failed to get config: %v", err)
+	}
+
+	// Test environment variable overrides
+	tests := []struct {
+		name     string
+		got      interface{}
+		expected interface{}
+	}{
+		{"server.addr", cfg.Server.Addr, ":9090"},
+		{"tracing.enabled", cfg.Tracing.Enabled, true},
+		{"cache.provider", cfg.Cache.Provider, "redis"},
+		{"logger.dev", cfg.Logger.Dev, true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if tt.got != tt.expected {
+				t.Errorf("%s: got %v, want %v", tt.name, tt.got, tt.expected)
+			}
+		})
+	}
+}
+
+func TestProgrammaticConfiguration(t *testing.T) {
+	mgr := NewManager()
+	mgr.Set("server.addr", ":7070")
+	mgr.Set("tracing.service_name", "test-service")
+
+	cfg, err := mgr.GetConfig()
+	if err != nil {
+		t.Fatalf("Failed to get config: %v", err)
+	}
+
+	if cfg.Server.Addr != ":7070" {
+		t.Errorf("server.addr: got %s, want :7070", cfg.Server.Addr)
+	}
+
+	if cfg.Tracing.ServiceName != "test-service" {
+		t.Errorf("tracing.service_name: got %s, want test-service", cfg.Tracing.ServiceName)
+	}
+}
+
+func TestGetterMethods(t *testing.T) {
+	mgr := NewManager()
+	mgr.Set("test.string", "value")
+	mgr.Set("test.int", 42)
+	mgr.Set("test.bool", true)
+
+	if got := mgr.GetString("test.string"); got != "value" {
+		t.Errorf("GetString: got %s, want value", got)
+	}
+
+	if got := mgr.GetInt("test.int"); got != 42 {
+		t.Errorf("GetInt: got %d, want 42", got)
+	}
+
+	if got := mgr.GetBool("test.bool"); !got {
+		t.Errorf("GetBool: got %v, want true", got)
+	}
+}
+
+func TestWithOptions(t *testing.T) {
+	mgr := NewManagerWithOptions(
+		WithEnvPrefix("MYAPP"),
+		WithConfigName("myconfig"),
+	)
+
+	if mgr == nil {
+		t.Fatal("Expected manager to be non-nil")
+	}
+
+	// Set environment variable with custom prefix
+	os.Setenv("MYAPP_SERVER_ADDR", ":5000")
+	defer os.Unsetenv("MYAPP_SERVER_ADDR")
+
+	if err := mgr.Load(); err != nil {
+		t.Fatalf("Failed to load config: %v", err)
+	}
+
+	cfg, err := mgr.GetConfig()
+	if err != nil {
+		t.Fatalf("Failed to get config: %v", err)
+	}
+
+	if cfg.Server.Addr != ":5000" {
+		t.Errorf("server.addr: got %s, want :5000", cfg.Server.Addr)
+	}
+}

pkg/funcspec/function_api_test.go

@@ -0,0 +1,906 @@
+package funcspec
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"strings"
+	"testing"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+	"github.com/bitechdev/ResolveSpec/pkg/security"
+)
+
+// MockDatabase implements common.Database interface for testing
+type MockDatabase struct {
+	QueryFunc            func(ctx context.Context, dest interface{}, query string, args ...interface{}) error
+	ExecFunc             func(ctx context.Context, query string, args ...interface{}) (common.Result, error)
+	RunInTransactionFunc func(ctx context.Context, fn func(common.Database) error) error
+}
+
+func (m *MockDatabase) NewSelect() common.SelectQuery {
+	return nil
+}
+
+func (m *MockDatabase) NewInsert() common.InsertQuery {
+	return nil
+}
+
+func (m *MockDatabase) NewUpdate() common.UpdateQuery {
+	return nil
+}
+
+func (m *MockDatabase) NewDelete() common.DeleteQuery {
+	return nil
+}
+
+func (m *MockDatabase) Exec(ctx context.Context, query string, args ...interface{}) (common.Result, error) {
+	if m.ExecFunc != nil {
+		return m.ExecFunc(ctx, query, args...)
+	}
+	return &MockResult{rows: 0}, nil
+}
+
+func (m *MockDatabase) Query(ctx context.Context, dest interface{}, query string, args ...interface{}) error {
+	if m.QueryFunc != nil {
+		return m.QueryFunc(ctx, dest, query, args...)
+	}
+	return nil
+}
+
+func (m *MockDatabase) BeginTx(ctx context.Context) (common.Database, error) {
+	return m, nil
+}
+
+func (m *MockDatabase) CommitTx(ctx context.Context) error {
+	return nil
+}
+
+func (m *MockDatabase) RollbackTx(ctx context.Context) error {
+	return nil
+}
+
+func (m *MockDatabase) RunInTransaction(ctx context.Context, fn func(common.Database) error) error {
+	if m.RunInTransactionFunc != nil {
+		return m.RunInTransactionFunc(ctx, fn)
+	}
+	return fn(m)
+}
+
+// MockResult implements common.Result interface for testing
+type MockResult struct {
+	rows int64
+	id   int64
+}
+
+func (m *MockResult) RowsAffected() int64 {
+	return m.rows
+}
+
+func (m *MockResult) LastInsertId() (int64, error) {
+	return m.id, nil
+}
+
+// Helper function to create a test request with user context
+func createTestRequest(method, path string, queryParams map[string]string, headers map[string]string, body []byte) *http.Request {
+	u, _ := url.Parse(path)
+	if queryParams != nil {
+		q := u.Query()
+		for k, v := range queryParams {
+			q.Set(k, v)
+		}
+		u.RawQuery = q.Encode()
+	}
+
+	var bodyReader *bytes.Reader
+	if body != nil {
+		bodyReader = bytes.NewReader(body)
+	} else {
+		bodyReader = bytes.NewReader([]byte{})
+	}
+
+	req := httptest.NewRequest(method, u.String(), bodyReader)
+
+	if headers != nil {
+		for k, v := range headers {
+			req.Header.Set(k, v)
+		}
+	}
+
+	// Add user context
+	userCtx := &security.UserContext{
+		UserID:    1,
+		UserName:  "testuser",
+		SessionID: "test-session-123",
+	}
+	ctx := context.WithValue(req.Context(), security.UserContextKey, userCtx)
+	req = req.WithContext(ctx)
+
+	return req
+}
+
+// TestNewHandler tests handler creation
+func TestNewHandler(t *testing.T) {
+	db := &MockDatabase{}
+	handler := NewHandler(db)
+
+	if handler == nil {
+		t.Fatal("Expected handler to be created, got nil")
+	}
+
+	if handler.db != db {
+		t.Error("Expected handler to have the provided database")
+	}
+
+	if handler.hooks == nil {
+		t.Error("Expected handler to have a hook registry")
+	}
+}
+
+// TestHandlerHooks tests the Hooks method
+func TestHandlerHooks(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+	hooks := handler.Hooks()
+
+	if hooks == nil {
+		t.Fatal("Expected hooks registry to be non-nil")
+	}
+
+	// Should return the same instance
+	hooks2 := handler.Hooks()
+	if hooks != hooks2 {
+		t.Error("Expected Hooks() to return the same registry instance")
+	}
+}
+
+// TestExtractInputVariables tests the extractInputVariables function
+func TestExtractInputVariables(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+
+	tests := []struct {
+		name         string
+		sqlQuery     string
+		expectedVars []string
+	}{
+		{
+			name:         "No variables",
+			sqlQuery:     "SELECT * FROM users",
+			expectedVars: []string{},
+		},
+		{
+			name:         "Single variable",
+			sqlQuery:     "SELECT * FROM users WHERE id = [user_id]",
+			expectedVars: []string{"[user_id]"},
+		},
+		{
+			name:         "Multiple variables",
+			sqlQuery:     "SELECT * FROM users WHERE id = [user_id] AND name = [user_name]",
+			expectedVars: []string{"[user_id]", "[user_name]"},
+		},
+		{
+			name:         "Nested brackets",
+			sqlQuery:     "SELECT * FROM users WHERE data::jsonb @> '[field]'::jsonb AND id = [user_id]",
+			expectedVars: []string{"[field]", "[user_id]"},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			inputvars := make([]string, 0)
+			result := handler.extractInputVariables(tt.sqlQuery, &inputvars)
+
+			if result != tt.sqlQuery {
+				t.Errorf("Expected SQL query to be unchanged, got %s", result)
+			}
+
+			if len(inputvars) != len(tt.expectedVars) {
+				t.Errorf("Expected %d variables, got %d: %v", len(tt.expectedVars), len(inputvars), inputvars)
+				return
+			}
+
+			for i, expected := range tt.expectedVars {
+				if inputvars[i] != expected {
+					t.Errorf("Expected variable %d to be %s, got %s", i, expected, inputvars[i])
+				}
+			}
+		})
+	}
+}
+
+// TestValidSQL tests the SQL sanitization function
+func TestValidSQL(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		mode     string
+		expected string
+	}{
+		{
+			name:     "Column name with valid characters",
+			input:    "user_id",
+			mode:     "colname",
+			expected: "user_id",
+		},
+		{
+			name:     "Column name with dots (table.column)",
+			input:    "users.user_id",
+			mode:     "colname",
+			expected: "users.user_id",
+		},
+		{
+			name:     "Column name with SQL injection attempt",
+			input:    "id'; DROP TABLE users--",
+			mode:     "colname",
+			expected: "idDROPTABLEusers",
+		},
+		{
+			name:     "Column value with single quotes",
+			input:    "O'Brien",
+			mode:     "colvalue",
+			expected: "O''Brien",
+		},
+		{
+			name:     "Select with dangerous keywords",
+			input:    "name, email; DROP TABLE users",
+			mode:     "select",
+			expected: "name, email TABLE users",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := ValidSQL(tt.input, tt.mode)
+			if result != tt.expected {
+				t.Errorf("ValidSQL(%q, %q) = %q, expected %q", tt.input, tt.mode, result, tt.expected)
+			}
+		})
+	}
+}
+
+// TestIsNumeric tests the IsNumeric function
+func TestIsNumeric(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected bool
+	}{
+		{"123", true},
+		{"123.45", true},
+		{"-123", true},
+		{"-123.45", true},
+		{"0", true},
+		{"abc", false},
+		{"12.34.56", false},
+		{"", false},
+		{"123abc", false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			result := IsNumeric(tt.input)
+			if result != tt.expected {
+				t.Errorf("IsNumeric(%q) = %v, expected %v", tt.input, result, tt.expected)
+			}
+		})
+	}
+}
+
+// TestSqlQryWhere tests the WHERE clause manipulation
+func TestSqlQryWhere(t *testing.T) {
+	tests := []struct {
+		name      string
+		sqlQuery  string
+		condition string
+		expected  string
+	}{
+		{
+			name:      "Add WHERE to query without WHERE",
+			sqlQuery:  "SELECT * FROM users",
+			condition: "status = 'active'",
+			expected:  "SELECT * FROM users WHERE status = 'active' ",
+		},
+		{
+			name:      "Add AND to query with existing WHERE",
+			sqlQuery:  "SELECT * FROM users WHERE id > 0",
+			condition: "status = 'active'",
+			expected:  "SELECT * FROM users WHERE id > 0 AND status = 'active' ",
+		},
+		{
+			name:      "Add WHERE before ORDER BY",
+			sqlQuery:  "SELECT * FROM users ORDER BY name",
+			condition: "status = 'active'",
+			expected:  "SELECT * FROM users WHERE status = 'active'  ORDER BY name",
+		},
+		{
+			name:      "Add WHERE before GROUP BY",
+			sqlQuery:  "SELECT COUNT(*) FROM users GROUP BY department",
+			condition: "status = 'active'",
+			expected:  "SELECT COUNT(*) FROM users WHERE status = 'active'  GROUP BY department",
+		},
+		{
+			name:      "Add WHERE before LIMIT",
+			sqlQuery:  "SELECT * FROM users LIMIT 10",
+			condition: "status = 'active'",
+			expected:  "SELECT * FROM users WHERE status = 'active'  LIMIT 10",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := sqlQryWhere(tt.sqlQuery, tt.condition)
+			if result != tt.expected {
+				t.Errorf("sqlQryWhere() = %q, expected %q", result, tt.expected)
+			}
+		})
+	}
+}
+
+// TestGetIPAddress tests IP address extraction
+func TestGetIPAddress(t *testing.T) {
+	tests := []struct {
+		name     string
+		setupReq func() *http.Request
+		expected string
+	}{
+		{
+			name: "X-Forwarded-For header",
+			setupReq: func() *http.Request {
+				req := httptest.NewRequest("GET", "/test", nil)
+				req.Header.Set("X-Forwarded-For", "192.168.1.100, 10.0.0.1")
+				return req
+			},
+			expected: "192.168.1.100",
+		},
+		{
+			name: "X-Real-IP header",
+			setupReq: func() *http.Request {
+				req := httptest.NewRequest("GET", "/test", nil)
+				req.Header.Set("X-Real-IP", "192.168.1.200")
+				return req
+			},
+			expected: "192.168.1.200",
+		},
+		{
+			name: "RemoteAddr fallback",
+			setupReq: func() *http.Request {
+				req := httptest.NewRequest("GET", "/test", nil)
+				req.RemoteAddr = "192.168.1.1:12345"
+				return req
+			},
+			expected: "192.168.1.1:12345",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := tt.setupReq()
+			result := getIPAddress(req)
+			if result != tt.expected {
+				t.Errorf("getIPAddress() = %q, expected %q", result, tt.expected)
+			}
+		})
+	}
+}
+
+// TestParsePaginationParams tests pagination parameter parsing
+func TestParsePaginationParams(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+
+	tests := []struct {
+		name           string
+		queryParams    map[string]string
+		expectedSort   string
+		expectedLimit  int
+		expectedOffset int
+	}{
+		{
+			name:           "No parameters - defaults",
+			queryParams:    map[string]string{},
+			expectedSort:   "",
+			expectedLimit:  20,
+			expectedOffset: 0,
+		},
+		{
+			name: "All parameters provided",
+			queryParams: map[string]string{
+				"sort":   "name,-created_at",
+				"limit":  "100",
+				"offset": "50",
+			},
+			expectedSort:   "name,-created_at",
+			expectedLimit:  100,
+			expectedOffset: 50,
+		},
+		{
+			name: "Invalid limit - use default",
+			queryParams: map[string]string{
+				"limit": "invalid",
+			},
+			expectedSort:   "",
+			expectedLimit:  20,
+			expectedOffset: 0,
+		},
+		{
+			name: "Negative offset - use default",
+			queryParams: map[string]string{
+				"offset": "-10",
+			},
+			expectedSort:   "",
+			expectedLimit:  20,
+			expectedOffset: 0,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := createTestRequest("GET", "/test", tt.queryParams, nil, nil)
+			sort, limit, offset := handler.parsePaginationParams(req)
+
+			if sort != tt.expectedSort {
+				t.Errorf("Expected sort=%q, got %q", tt.expectedSort, sort)
+			}
+			if limit != tt.expectedLimit {
+				t.Errorf("Expected limit=%d, got %d", tt.expectedLimit, limit)
+			}
+			if offset != tt.expectedOffset {
+				t.Errorf("Expected offset=%d, got %d", tt.expectedOffset, offset)
+			}
+		})
+	}
+}
+
+// TestSqlQuery tests the SqlQuery handler for single record queries
+func TestSqlQuery(t *testing.T) {
+	tests := []struct {
+		name           string
+		sqlQuery       string
+		blankParams    bool
+		queryParams    map[string]string
+		headers        map[string]string
+		setupDB        func() *MockDatabase
+		expectedStatus int
+		validateResp   func(t *testing.T, body []byte)
+	}{
+		{
+			name:        "Basic query - returns single record",
+			sqlQuery:    "SELECT * FROM users WHERE id = 1",
+			blankParams: false,
+			setupDB: func() *MockDatabase {
+				return &MockDatabase{
+					RunInTransactionFunc: func(ctx context.Context, fn func(common.Database) error) error {
+						db := &MockDatabase{
+							QueryFunc: func(ctx context.Context, dest interface{}, query string, args ...interface{}) error {
+								rows := dest.(*[]map[string]interface{})
+								*rows = []map[string]interface{}{
+									{"id": float64(1), "name": "Test User", "email": "test@example.com"},
+								}
+								return nil
+							},
+						}
+						return fn(db)
+					},
+				}
+			},
+			expectedStatus: 200,
+			validateResp: func(t *testing.T, body []byte) {
+				var result map[string]interface{}
+				if err := json.Unmarshal(body, &result); err != nil {
+					t.Fatalf("Failed to unmarshal response: %v", err)
+				}
+				if result["name"] != "Test User" {
+					t.Errorf("Expected name='Test User', got %v", result["name"])
+				}
+			},
+		},
+		{
+			name:        "Query with no results",
+			sqlQuery:    "SELECT * FROM users WHERE id = 999",
+			blankParams: false,
+			setupDB: func() *MockDatabase {
+				return &MockDatabase{
+					RunInTransactionFunc: func(ctx context.Context, fn func(common.Database) error) error {
+						db := &MockDatabase{
+							QueryFunc: func(ctx context.Context, dest interface{}, query string, args ...interface{}) error {
+								// Return empty array
+								return nil
+							},
+						}
+						return fn(db)
+					},
+				}
+			},
+			expectedStatus: 200,
+			validateResp: func(t *testing.T, body []byte) {
+				var result map[string]interface{}
+				if err := json.Unmarshal(body, &result); err != nil {
+					t.Fatalf("Failed to unmarshal response: %v", err)
+				}
+				if len(result) != 0 {
+					t.Errorf("Expected empty result, got %v", result)
+				}
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			db := tt.setupDB()
+			handler := NewHandler(db)
+
+			req := createTestRequest("GET", "/test", tt.queryParams, tt.headers, nil)
+			w := httptest.NewRecorder()
+
+			handlerFunc := handler.SqlQuery(tt.sqlQuery, tt.blankParams)
+			handlerFunc(w, req)
+
+			if w.Code != tt.expectedStatus {
+				t.Errorf("Expected status %d, got %d", tt.expectedStatus, w.Code)
+			}
+
+			if tt.validateResp != nil {
+				tt.validateResp(t, w.Body.Bytes())
+			}
+		})
+	}
+}
+
+// TestSqlQueryList tests the SqlQueryList handler for list queries
+func TestSqlQueryList(t *testing.T) {
+	tests := []struct {
+		name           string
+		sqlQuery       string
+		noCount        bool
+		blankParams    bool
+		allowFilter    bool
+		queryParams    map[string]string
+		headers        map[string]string
+		setupDB        func() *MockDatabase
+		expectedStatus int
+		validateResp   func(t *testing.T, w *httptest.ResponseRecorder)
+	}{
+		{
+			name:        "Basic list query",
+			sqlQuery:    "SELECT * FROM users",
+			noCount:     false,
+			blankParams: false,
+			allowFilter: false,
+			setupDB: func() *MockDatabase {
+				return &MockDatabase{
+					RunInTransactionFunc: func(ctx context.Context, fn func(common.Database) error) error {
+						callCount := 0
+						db := &MockDatabase{
+							QueryFunc: func(ctx context.Context, dest interface{}, query string, args ...interface{}) error {
+								callCount++
+								if strings.Contains(query, "COUNT") {
+									// Count query
+									countResult := dest.(*struct{ Count int64 })
+									countResult.Count = 2
+								} else {
+									// Main query
+									rows := dest.(*[]map[string]interface{})
+									*rows = []map[string]interface{}{
+										{"id": float64(1), "name": "User 1"},
+										{"id": float64(2), "name": "User 2"},
+									}
+								}
+								return nil
+							},
+						}
+						return fn(db)
+					},
+				}
+			},
+			expectedStatus: 200,
+			validateResp: func(t *testing.T, w *httptest.ResponseRecorder) {
+				var result []map[string]interface{}
+				if err := json.Unmarshal(w.Body.Bytes(), &result); err != nil {
+					t.Fatalf("Failed to unmarshal response: %v", err)
+				}
+				if len(result) != 2 {
+					t.Errorf("Expected 2 results, got %d", len(result))
+				}
+
+				// Check Content-Range header
+				contentRange := w.Header().Get("Content-Range")
+				if !strings.Contains(contentRange, "2") {
+					t.Errorf("Expected Content-Range to contain total count, got: %s", contentRange)
+				}
+			},
+		},
+		{
+			name:        "List query with noCount",
+			sqlQuery:    "SELECT * FROM users",
+			noCount:     true,
+			blankParams: false,
+			allowFilter: false,
+			setupDB: func() *MockDatabase {
+				return &MockDatabase{
+					RunInTransactionFunc: func(ctx context.Context, fn func(common.Database) error) error {
+						db := &MockDatabase{
+							QueryFunc: func(ctx context.Context, dest interface{}, query string, args ...interface{}) error {
+								if strings.Contains(query, "COUNT") {
+									t.Error("Count query should not be executed when noCount is true")
+								}
+								rows := dest.(*[]map[string]interface{})
+								*rows = []map[string]interface{}{
+									{"id": float64(1), "name": "User 1"},
+								}
+								return nil
+							},
+						}
+						return fn(db)
+					},
+				}
+			},
+			expectedStatus: 200,
+			validateResp: func(t *testing.T, w *httptest.ResponseRecorder) {
+				var result []map[string]interface{}
+				if err := json.Unmarshal(w.Body.Bytes(), &result); err != nil {
+					t.Fatalf("Failed to unmarshal response: %v", err)
+				}
+				if len(result) != 1 {
+					t.Errorf("Expected 1 result, got %d", len(result))
+				}
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			db := tt.setupDB()
+			handler := NewHandler(db)
+
+			req := createTestRequest("GET", "/test", tt.queryParams, tt.headers, nil)
+			w := httptest.NewRecorder()
+
+			handlerFunc := handler.SqlQueryList(tt.sqlQuery, tt.noCount, tt.blankParams, tt.allowFilter)
+			handlerFunc(w, req)
+
+			if w.Code != tt.expectedStatus {
+				t.Errorf("Expected status %d, got %d. Body: %s", tt.expectedStatus, w.Code, w.Body.String())
+			}
+
+			if tt.validateResp != nil {
+				tt.validateResp(t, w)
+			}
+		})
+	}
+}
+
+// TestMergeQueryParams tests query parameter merging
+func TestMergeQueryParams(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+
+	tests := []struct {
+		name          string
+		sqlQuery      string
+		queryParams   map[string]string
+		allowFilter   bool
+		expectedQuery string
+		checkVars     func(t *testing.T, vars map[string]interface{})
+	}{
+		{
+			name:        "Replace placeholder with parameter",
+			sqlQuery:    "SELECT * FROM users WHERE id = [user_id]",
+			queryParams: map[string]string{"p-user_id": "123"},
+			allowFilter: false,
+			checkVars: func(t *testing.T, vars map[string]interface{}) {
+				if vars["p-user_id"] != "123" {
+					t.Errorf("Expected p-user_id=123, got %v", vars["p-user_id"])
+				}
+			},
+		},
+		{
+			name:        "Add filter when allowed",
+			sqlQuery:    "SELECT * FROM users",
+			queryParams: map[string]string{"status": "active"},
+			allowFilter: true,
+			checkVars: func(t *testing.T, vars map[string]interface{}) {
+				if vars["status"] != "active" {
+					t.Errorf("Expected status=active, got %v", vars["status"])
+				}
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := createTestRequest("GET", "/test", tt.queryParams, nil, nil)
+			variables := make(map[string]interface{})
+			propQry := make(map[string]string)
+
+			result := handler.mergeQueryParams(req, tt.sqlQuery, variables, tt.allowFilter, propQry)
+
+			if result == "" {
+				t.Error("Expected non-empty SQL query result")
+			}
+
+			if tt.checkVars != nil {
+				tt.checkVars(t, variables)
+			}
+		})
+	}
+}
+
+// TestMergeHeaderParams tests header parameter merging
+func TestMergeHeaderParams(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+
+	tests := []struct {
+		name          string
+		sqlQuery      string
+		headers       map[string]string
+		expectedQuery string
+		checkVars     func(t *testing.T, vars map[string]interface{})
+	}{
+		{
+			name:     "Field filter header",
+			sqlQuery: "SELECT * FROM users",
+			headers:  map[string]string{"X-FieldFilter-Status": "1"},
+			checkVars: func(t *testing.T, vars map[string]interface{}) {
+				if vars["x-fieldfilter-status"] != "1" {
+					t.Errorf("Expected x-fieldfilter-status=1, got %v", vars["x-fieldfilter-status"])
+				}
+			},
+		},
+		{
+			name:     "Search filter header",
+			sqlQuery: "SELECT * FROM users",
+			headers:  map[string]string{"X-SearchFilter-Name": "john"},
+			checkVars: func(t *testing.T, vars map[string]interface{}) {
+				if vars["x-searchfilter-name"] != "john" {
+					t.Errorf("Expected x-searchfilter-name=john, got %v", vars["x-searchfilter-name"])
+				}
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := createTestRequest("GET", "/test", nil, tt.headers, nil)
+			variables := make(map[string]interface{})
+			propQry := make(map[string]string)
+			complexAPI := false
+
+			result := handler.mergeHeaderParams(req, tt.sqlQuery, variables, propQry, &complexAPI)
+
+			if result == "" {
+				t.Error("Expected non-empty SQL query result")
+			}
+
+			if tt.checkVars != nil {
+				tt.checkVars(t, variables)
+			}
+		})
+	}
+}
+
+// TestReplaceMetaVariables tests meta variable replacement
+func TestReplaceMetaVariables(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+
+	userCtx := &security.UserContext{
+		UserID:     123,
+		UserName:   "testuser",
+		SessionID:  "ABC456",
+		SessionRID: 456,
+	}
+
+	metainfo := map[string]interface{}{
+		"ipaddress": "192.168.1.1",
+		"url":       "/api/test",
+	}
+
+	variables := map[string]interface{}{
+		"param1": "value1",
+	}
+
+	tests := []struct {
+		name          string
+		sqlQuery      string
+		expectedCheck func(result string) bool
+	}{
+		{
+			name:     "Replace [rid_user]",
+			sqlQuery: "SELECT * FROM users WHERE created_by = [rid_user]",
+			expectedCheck: func(result string) bool {
+				return strings.Contains(result, "123")
+			},
+		},
+		{
+			name:     "Replace [user]",
+			sqlQuery: "SELECT * FROM audit WHERE username = [user]",
+			expectedCheck: func(result string) bool {
+				return strings.Contains(result, "'testuser'")
+			},
+		},
+		{
+			name:     "Replace [rid_session]",
+			sqlQuery: "SELECT * FROM sessions WHERE session_id = [rid_session]",
+			expectedCheck: func(result string) bool {
+				return strings.Contains(result, "456")
+			},
+		}, {
+			name:     "Replace [id_session]",
+			sqlQuery: "SELECT * FROM sessions WHERE session_id = [id_session]",
+			expectedCheck: func(result string) bool {
+				return strings.Contains(result, "ABC456")
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := createTestRequest("GET", "/test", nil, nil, nil)
+			result := handler.replaceMetaVariables(tt.sqlQuery, req, userCtx, metainfo, variables)
+
+			if !tt.expectedCheck(result) {
+				t.Errorf("Meta variable replacement failed. Query: %s", result)
+			}
+		})
+	}
+}
+
+// TestGetReplacementForBlankParam tests the blank parameter replacement logic
+func TestGetReplacementForBlankParam(t *testing.T) {
+	tests := []struct {
+		name     string
+		sqlQuery string
+		param    string
+		expected string
+	}{
+		{
+			name:     "Parameter in single quotes",
+			sqlQuery: "SELECT * FROM users WHERE name = '[username]'",
+			param:    "[username]",
+			expected: "",
+		},
+		{
+			name:     "Parameter in dollar quotes",
+			sqlQuery: "SELECT * FROM users WHERE data = $[jsondata]$",
+			param:    "[jsondata]",
+			expected: "",
+		},
+		{
+			name:     "Parameter not in quotes",
+			sqlQuery: "SELECT * FROM users WHERE id = [user_id]",
+			param:    "[user_id]",
+			expected: "NULL",
+		},
+		{
+			name:     "Parameter not in quotes with AND",
+			sqlQuery: "SELECT * FROM users WHERE id = [user_id] AND status = 1",
+			param:    "[user_id]",
+			expected: "NULL",
+		},
+		{
+			name:     "Parameter in mixed quote context - before quote",
+			sqlQuery: "SELECT * FROM users WHERE id = [user_id] AND name = 'test'",
+			param:    "[user_id]",
+			expected: "NULL",
+		},
+		{
+			name:     "Parameter in mixed quote context - in quotes",
+			sqlQuery: "SELECT * FROM users WHERE name = '[username]' AND id = 1",
+			param:    "[username]",
+			expected: "",
+		},
+		{
+			name:     "Parameter with dollar quote tag",
+			sqlQuery: "SELECT * FROM users WHERE body = $tag$[content]$tag$",
+			param:    "[content]",
+			expected: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := getReplacementForBlankParam(tt.sqlQuery, tt.param)
+			if result != tt.expected {
+				t.Errorf("Expected replacement '%s', got '%s' for query: %s", tt.expected, result, tt.sqlQuery)
+			}
+		})
+	}
+}

pkg/funcspec/hooks.go

@@ -0,0 +1,160 @@
+package funcspec
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
+	"github.com/bitechdev/ResolveSpec/pkg/security"
+)
+
+// HookType defines the type of hook to execute
+type HookType string
+
+const (
+	// Query operation hooks (for SqlQuery - single record)
+	BeforeQuery HookType = "before_query"
+	AfterQuery  HookType = "after_query"
+
+	// Query list operation hooks (for SqlQueryList - multiple records)
+	BeforeQueryList HookType = "before_query_list"
+	AfterQueryList  HookType = "after_query_list"
+
+	// SQL execution hooks (just before SQL is executed)
+	BeforeSQLExec HookType = "before_sql_exec"
+	AfterSQLExec  HookType = "after_sql_exec"
+
+	// Response hooks (before response is sent)
+	BeforeResponse HookType = "before_response"
+)
+
+// HookContext contains all the data available to a hook
+type HookContext struct {
+	Context context.Context
+	Handler *Handler // Reference to the handler for accessing database
+	Request *http.Request
+	Writer  http.ResponseWriter
+
+	// SQL query and variables
+	SQLQuery  string                 // The SQL query being executed (can be modified by hooks)
+	Variables map[string]interface{} // Variables extracted from request
+	InputVars []string               // Input variable placeholders found in query
+	MetaInfo  map[string]interface{} // Metadata about the request
+	PropQry   map[string]string      // Property query parameters
+
+	// User context
+	UserContext *security.UserContext
+
+	// Pagination and filtering (for list queries)
+	SortColumns string
+	Limit       int
+	Offset      int
+
+	// Results
+	Result      interface{} // Query result (single record or list)
+	Total       int64       // Total count (for list queries)
+	Error       error       // Error if operation failed
+	ComplexAPI  bool        // Whether complex API response format is requested
+	NoCount     bool        // Whether count query should be skipped
+	BlankParams bool        // Whether blank parameters should be removed
+	AllowFilter bool        // Whether filtering is allowed
+
+	// Allow hooks to abort the operation
+	Abort        bool   // If set to true, the operation will be aborted
+	AbortMessage string // Message to return if aborted
+	AbortCode    int    // HTTP status code if aborted
+}
+
+// HookFunc is the signature for hook functions
+// It receives a HookContext and can modify it or return an error
+// If an error is returned, the operation will be aborted
+type HookFunc func(*HookContext) error
+
+// HookRegistry manages all registered hooks
+type HookRegistry struct {
+	hooks map[HookType][]HookFunc
+}
+
+// NewHookRegistry creates a new hook registry
+func NewHookRegistry() *HookRegistry {
+	return &HookRegistry{
+		hooks: make(map[HookType][]HookFunc),
+	}
+}
+
+// Register adds a new hook for the specified hook type
+func (r *HookRegistry) Register(hookType HookType, hook HookFunc) {
+	if r.hooks == nil {
+		r.hooks = make(map[HookType][]HookFunc)
+	}
+	r.hooks[hookType] = append(r.hooks[hookType], hook)
+	logger.Info("Registered funcspec hook for %s (total: %d)", hookType, len(r.hooks[hookType]))
+}
+
+// RegisterMultiple registers a hook for multiple hook types
+func (r *HookRegistry) RegisterMultiple(hookTypes []HookType, hook HookFunc) {
+	for _, hookType := range hookTypes {
+		r.Register(hookType, hook)
+	}
+}
+
+// Execute runs all hooks for the specified type in order
+// If any hook returns an error, execution stops and the error is returned
+func (r *HookRegistry) Execute(hookType HookType, ctx *HookContext) error {
+	hooks, exists := r.hooks[hookType]
+	if !exists || len(hooks) == 0 {
+		return nil
+	}
+
+	logger.Debug("Executing %d funcspec hook(s) for %s", len(hooks), hookType)
+
+	for i, hook := range hooks {
+		if err := hook(ctx); err != nil {
+			logger.Error("Funcspec hook %d for %s failed: %v", i+1, hookType, err)
+			return fmt.Errorf("hook execution failed: %w", err)
+		}
+
+		// Check if hook requested abort
+		if ctx.Abort {
+			logger.Warn("Funcspec hook %d for %s requested abort: %s", i+1, hookType, ctx.AbortMessage)
+			return fmt.Errorf("operation aborted by hook: %s", ctx.AbortMessage)
+		}
+	}
+
+	return nil
+}
+
+// Clear removes all hooks for the specified type
+func (r *HookRegistry) Clear(hookType HookType) {
+	delete(r.hooks, hookType)
+	logger.Info("Cleared all funcspec hooks for %s", hookType)
+}
+
+// ClearAll removes all registered hooks
+func (r *HookRegistry) ClearAll() {
+	r.hooks = make(map[HookType][]HookFunc)
+	logger.Info("Cleared all funcspec hooks")
+}
+
+// Count returns the number of hooks registered for a specific type
+func (r *HookRegistry) Count(hookType HookType) int {
+	if hooks, exists := r.hooks[hookType]; exists {
+		return len(hooks)
+	}
+	return 0
+}
+
+// HasHooks returns true if there are any hooks registered for the specified type
+func (r *HookRegistry) HasHooks(hookType HookType) bool {
+	return r.Count(hookType) > 0
+}
+
+// GetAllHookTypes returns all hook types that have registered hooks
+func (r *HookRegistry) GetAllHookTypes() []HookType {
+	types := make([]HookType, 0, len(r.hooks))
+	for hookType := range r.hooks {
+		types = append(types, hookType)
+	}
+	return types
+}

pkg/funcspec/hooks_example.go

@@ -0,0 +1,137 @@
+package funcspec
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
+)
+
+// Example hook functions demonstrating various use cases
+
+// ExampleLoggingHook logs all SQL queries before execution
+func ExampleLoggingHook(ctx *HookContext) error {
+	logger.Info("Executing SQL query for user %s: %s", ctx.UserContext.UserName, ctx.SQLQuery)
+	return nil
+}
+
+// ExampleSecurityHook validates user permissions before executing queries
+func ExampleSecurityHook(ctx *HookContext) error {
+	// Example: Block queries that try to access sensitive tables
+	if strings.Contains(strings.ToLower(ctx.SQLQuery), "sensitive_table") {
+		if ctx.UserContext.UserID != 1 { // Only admin can access
+			ctx.Abort = true
+			ctx.AbortCode = 403
+			ctx.AbortMessage = "Access denied: insufficient permissions"
+			return fmt.Errorf("access denied to sensitive_table")
+		}
+	}
+	return nil
+}
+
+// ExampleQueryModificationHook modifies SQL queries to add user-specific filtering
+func ExampleQueryModificationHook(ctx *HookContext) error {
+	// Example: Automatically add user_id filter for non-admin users
+	if ctx.UserContext.UserID != 1 { // Not admin
+		// Add WHERE clause to filter by user_id
+		if !strings.Contains(strings.ToLower(ctx.SQLQuery), "where") {
+			ctx.SQLQuery = fmt.Sprintf("%s WHERE user_id = %d", ctx.SQLQuery, ctx.UserContext.UserID)
+		} else {
+			ctx.SQLQuery = strings.Replace(
+				ctx.SQLQuery,
+				"WHERE",
+				fmt.Sprintf("WHERE user_id = %d AND", ctx.UserContext.UserID),
+				1,
+			)
+		}
+		logger.Debug("Modified query for user %d: %s", ctx.UserContext.UserID, ctx.SQLQuery)
+	}
+	return nil
+}
+
+// ExampleResultFilterHook filters results after query execution
+func ExampleResultFilterHook(ctx *HookContext) error {
+	// Example: Remove sensitive fields from results for non-admin users
+	if ctx.UserContext.UserID != 1 { // Not admin
+		switch result := ctx.Result.(type) {
+		case []map[string]interface{}:
+			// Filter list results
+			for i := range result {
+				delete(result[i], "password")
+				delete(result[i], "ssn")
+				delete(result[i], "credit_card")
+			}
+		case map[string]interface{}:
+			// Filter single record
+			delete(result, "password")
+			delete(result, "ssn")
+			delete(result, "credit_card")
+		}
+	}
+	return nil
+}
+
+// ExampleAuditHook logs all queries and results for audit purposes
+func ExampleAuditHook(ctx *HookContext) error {
+	// Log to audit table or external system
+	logger.Info("AUDIT: User %s (%d) executed query from %s",
+		ctx.UserContext.UserName,
+		ctx.UserContext.UserID,
+		ctx.Request.RemoteAddr,
+	)
+
+	// In a real implementation, you might:
+	// - Insert into an audit log table
+	// - Send to a logging service
+	// - Write to a file
+
+	return nil
+}
+
+// ExampleCacheHook implements simple response caching
+func ExampleCacheHook(ctx *HookContext) error {
+	// This is a simplified example - real caching would use a proper cache store
+	// Check if we have a cached result for this query
+	// cacheKey := fmt.Sprintf("%s:%s", ctx.UserContext.UserName, ctx.SQLQuery)
+	// if cachedResult := checkCache(cacheKey); cachedResult != nil {
+	//     ctx.Result = cachedResult
+	//     ctx.Abort = true // Skip query execution
+	//     ctx.AbortMessage = "Serving from cache"
+	// }
+	return nil
+}
+
+// ExampleErrorHandlingHook provides custom error handling
+func ExampleErrorHandlingHook(ctx *HookContext) error {
+	if ctx.Error != nil {
+		// Log error with context
+		logger.Error("Query failed for user %s: %v\nQuery: %s",
+			ctx.UserContext.UserName,
+			ctx.Error,
+			ctx.SQLQuery,
+		)
+
+		// You could send notifications, update metrics, etc.
+	}
+	return nil
+}
+
+// Example of registering hooks:
+//
+// func SetupHooks(handler *Handler) {
+//     hooks := handler.Hooks()
+//
+//     // Register security hook before query execution
+//     hooks.Register(BeforeQuery, ExampleSecurityHook)
+//     hooks.Register(BeforeQueryList, ExampleSecurityHook)
+//
+//     // Register logging hook before SQL execution
+//     hooks.Register(BeforeSQLExec, ExampleLoggingHook)
+//
+//     // Register result filtering after query
+//     hooks.Register(AfterQuery, ExampleResultFilterHook)
+//     hooks.Register(AfterQueryList, ExampleResultFilterHook)
+//
+//     // Register audit hook after execution
+//     hooks.RegisterMultiple([]HookType{AfterQuery, AfterQueryList}, ExampleAuditHook)
+// }

pkg/funcspec/hooks_test.go

@@ -0,0 +1,589 @@
+package funcspec
+
+import (
+	"context"
+	"fmt"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+	"github.com/bitechdev/ResolveSpec/pkg/security"
+)
+
+// TestNewHookRegistry tests hook registry creation
+func TestNewHookRegistry(t *testing.T) {
+	registry := NewHookRegistry()
+
+	if registry == nil {
+		t.Fatal("Expected registry to be created, got nil")
+	}
+
+	if registry.hooks == nil {
+		t.Error("Expected hooks map to be initialized")
+	}
+}
+
+// TestRegisterHook tests registering a single hook
+func TestRegisterHook(t *testing.T) {
+	registry := NewHookRegistry()
+
+	hookCalled := false
+	testHook := func(ctx *HookContext) error {
+		hookCalled = true
+		return nil
+	}
+
+	registry.Register(BeforeQuery, testHook)
+
+	if !registry.HasHooks(BeforeQuery) {
+		t.Error("Expected hook to be registered")
+	}
+
+	if registry.Count(BeforeQuery) != 1 {
+		t.Errorf("Expected 1 hook, got %d", registry.Count(BeforeQuery))
+	}
+
+	// Execute the hook
+	ctx := &HookContext{}
+	err := registry.Execute(BeforeQuery, ctx)
+	if err != nil {
+		t.Errorf("Hook execution failed: %v", err)
+	}
+
+	if !hookCalled {
+		t.Error("Expected hook to be called")
+	}
+}
+
+// TestRegisterMultipleHooks tests registering multiple hooks for same type
+func TestRegisterMultipleHooks(t *testing.T) {
+	registry := NewHookRegistry()
+
+	callOrder := []int{}
+
+	hook1 := func(ctx *HookContext) error {
+		callOrder = append(callOrder, 1)
+		return nil
+	}
+
+	hook2 := func(ctx *HookContext) error {
+		callOrder = append(callOrder, 2)
+		return nil
+	}
+
+	hook3 := func(ctx *HookContext) error {
+		callOrder = append(callOrder, 3)
+		return nil
+	}
+
+	registry.Register(BeforeQuery, hook1)
+	registry.Register(BeforeQuery, hook2)
+	registry.Register(BeforeQuery, hook3)
+
+	if registry.Count(BeforeQuery) != 3 {
+		t.Errorf("Expected 3 hooks, got %d", registry.Count(BeforeQuery))
+	}
+
+	// Execute hooks
+	ctx := &HookContext{}
+	err := registry.Execute(BeforeQuery, ctx)
+	if err != nil {
+		t.Errorf("Hook execution failed: %v", err)
+	}
+
+	// Verify hooks were called in order
+	if len(callOrder) != 3 {
+		t.Errorf("Expected 3 hooks to be called, got %d", len(callOrder))
+	}
+
+	for i, expected := range []int{1, 2, 3} {
+		if callOrder[i] != expected {
+			t.Errorf("Expected hook %d at position %d, got %d", expected, i, callOrder[i])
+		}
+	}
+}
+
+// TestRegisterMultipleHookTypes tests registering a hook for multiple types
+func TestRegisterMultipleHookTypes(t *testing.T) {
+	registry := NewHookRegistry()
+
+	callCount := 0
+	testHook := func(ctx *HookContext) error {
+		callCount++
+		return nil
+	}
+
+	hookTypes := []HookType{BeforeQuery, AfterQuery, BeforeSQLExec}
+	registry.RegisterMultiple(hookTypes, testHook)
+
+	// Verify hook is registered for all types
+	for _, hookType := range hookTypes {
+		if !registry.HasHooks(hookType) {
+			t.Errorf("Expected hook to be registered for %s", hookType)
+		}
+
+		if registry.Count(hookType) != 1 {
+			t.Errorf("Expected 1 hook for %s, got %d", hookType, registry.Count(hookType))
+		}
+	}
+
+	// Execute each hook type
+	ctx := &HookContext{}
+	for _, hookType := range hookTypes {
+		if err := registry.Execute(hookType, ctx); err != nil {
+			t.Errorf("Hook execution failed for %s: %v", hookType, err)
+		}
+	}
+
+	if callCount != 3 {
+		t.Errorf("Expected hook to be called 3 times, got %d", callCount)
+	}
+}
+
+// TestHookError tests hook error handling
+func TestHookError(t *testing.T) {
+	registry := NewHookRegistry()
+
+	expectedError := fmt.Errorf("test error")
+	errorHook := func(ctx *HookContext) error {
+		return expectedError
+	}
+
+	registry.Register(BeforeQuery, errorHook)
+
+	ctx := &HookContext{}
+	err := registry.Execute(BeforeQuery, ctx)
+
+	if err == nil {
+		t.Error("Expected error from hook, got nil")
+	}
+
+	if err.Error() != fmt.Sprintf("hook execution failed: %v", expectedError) {
+		t.Errorf("Expected error message to contain hook error, got: %v", err)
+	}
+}
+
+// TestHookAbort tests hook abort functionality
+func TestHookAbort(t *testing.T) {
+	registry := NewHookRegistry()
+
+	abortHook := func(ctx *HookContext) error {
+		ctx.Abort = true
+		ctx.AbortMessage = "Operation aborted by hook"
+		ctx.AbortCode = 403
+		return nil
+	}
+
+	registry.Register(BeforeQuery, abortHook)
+
+	ctx := &HookContext{}
+	err := registry.Execute(BeforeQuery, ctx)
+
+	if err == nil {
+		t.Error("Expected error when hook aborts, got nil")
+	}
+
+	if !ctx.Abort {
+		t.Error("Expected Abort to be true")
+	}
+
+	if ctx.AbortMessage != "Operation aborted by hook" {
+		t.Errorf("Expected abort message, got: %s", ctx.AbortMessage)
+	}
+
+	if ctx.AbortCode != 403 {
+		t.Errorf("Expected abort code 403, got: %d", ctx.AbortCode)
+	}
+}
+
+// TestHookChainWithError tests that hook chain stops on first error
+func TestHookChainWithError(t *testing.T) {
+	registry := NewHookRegistry()
+
+	callOrder := []int{}
+
+	hook1 := func(ctx *HookContext) error {
+		callOrder = append(callOrder, 1)
+		return nil
+	}
+
+	hook2 := func(ctx *HookContext) error {
+		callOrder = append(callOrder, 2)
+		return fmt.Errorf("error in hook 2")
+	}
+
+	hook3 := func(ctx *HookContext) error {
+		callOrder = append(callOrder, 3)
+		return nil
+	}
+
+	registry.Register(BeforeQuery, hook1)
+	registry.Register(BeforeQuery, hook2)
+	registry.Register(BeforeQuery, hook3)
+
+	ctx := &HookContext{}
+	err := registry.Execute(BeforeQuery, ctx)
+
+	if err == nil {
+		t.Error("Expected error from hook chain")
+	}
+
+	// Only first two hooks should have been called
+	if len(callOrder) != 2 {
+		t.Errorf("Expected 2 hooks to be called, got %d", len(callOrder))
+	}
+
+	if callOrder[0] != 1 || callOrder[1] != 2 {
+		t.Errorf("Expected hooks 1 and 2 to be called, got: %v", callOrder)
+	}
+}
+
+// TestClearHooks tests clearing hooks
+func TestClearHooks(t *testing.T) {
+	registry := NewHookRegistry()
+
+	testHook := func(ctx *HookContext) error {
+		return nil
+	}
+
+	registry.Register(BeforeQuery, testHook)
+	registry.Register(AfterQuery, testHook)
+
+	if !registry.HasHooks(BeforeQuery) {
+		t.Error("Expected BeforeQuery hook to be registered")
+	}
+
+	registry.Clear(BeforeQuery)
+
+	if registry.HasHooks(BeforeQuery) {
+		t.Error("Expected BeforeQuery hooks to be cleared")
+	}
+
+	if !registry.HasHooks(AfterQuery) {
+		t.Error("Expected AfterQuery hook to still be registered")
+	}
+}
+
+// TestClearAllHooks tests clearing all hooks
+func TestClearAllHooks(t *testing.T) {
+	registry := NewHookRegistry()
+
+	testHook := func(ctx *HookContext) error {
+		return nil
+	}
+
+	registry.Register(BeforeQuery, testHook)
+	registry.Register(AfterQuery, testHook)
+	registry.Register(BeforeSQLExec, testHook)
+
+	registry.ClearAll()
+
+	if registry.HasHooks(BeforeQuery) || registry.HasHooks(AfterQuery) || registry.HasHooks(BeforeSQLExec) {
+		t.Error("Expected all hooks to be cleared")
+	}
+}
+
+// TestGetAllHookTypes tests getting all registered hook types
+func TestGetAllHookTypes(t *testing.T) {
+	registry := NewHookRegistry()
+
+	testHook := func(ctx *HookContext) error {
+		return nil
+	}
+
+	registry.Register(BeforeQuery, testHook)
+	registry.Register(AfterQuery, testHook)
+
+	types := registry.GetAllHookTypes()
+
+	if len(types) != 2 {
+		t.Errorf("Expected 2 hook types, got %d", len(types))
+	}
+
+	// Verify the types are present
+	foundBefore := false
+	foundAfter := false
+	for _, hookType := range types {
+		if hookType == BeforeQuery {
+			foundBefore = true
+		}
+		if hookType == AfterQuery {
+			foundAfter = true
+		}
+	}
+
+	if !foundBefore || !foundAfter {
+		t.Error("Expected both BeforeQuery and AfterQuery hook types")
+	}
+}
+
+// TestHookContextModification tests that hooks can modify the context
+func TestHookContextModification(t *testing.T) {
+	registry := NewHookRegistry()
+
+	// Hook that modifies SQL query
+	modifyHook := func(ctx *HookContext) error {
+		ctx.SQLQuery = "SELECT * FROM modified_table"
+		ctx.Variables["new_var"] = "new_value"
+		return nil
+	}
+
+	registry.Register(BeforeQuery, modifyHook)
+
+	ctx := &HookContext{
+		SQLQuery:  "SELECT * FROM original_table",
+		Variables: make(map[string]interface{}),
+	}
+
+	err := registry.Execute(BeforeQuery, ctx)
+	if err != nil {
+		t.Errorf("Hook execution failed: %v", err)
+	}
+
+	if ctx.SQLQuery != "SELECT * FROM modified_table" {
+		t.Errorf("Expected SQL query to be modified, got: %s", ctx.SQLQuery)
+	}
+
+	if ctx.Variables["new_var"] != "new_value" {
+		t.Errorf("Expected variable to be added, got: %v", ctx.Variables)
+	}
+}
+
+// TestExampleHooks tests the example hooks
+func TestExampleLoggingHook(t *testing.T) {
+	ctx := &HookContext{
+		Context:  context.Background(),
+		SQLQuery: "SELECT * FROM test",
+		UserContext: &security.UserContext{
+			UserName: "testuser",
+		},
+	}
+
+	err := ExampleLoggingHook(ctx)
+	if err != nil {
+		t.Errorf("ExampleLoggingHook failed: %v", err)
+	}
+}
+
+func TestExampleSecurityHook(t *testing.T) {
+	tests := []struct {
+		name        string
+		sqlQuery    string
+		userID      int
+		shouldAbort bool
+	}{
+		{
+			name:        "Admin accessing sensitive table",
+			sqlQuery:    "SELECT * FROM sensitive_table",
+			userID:      1,
+			shouldAbort: false,
+		},
+		{
+			name:        "Non-admin accessing sensitive table",
+			sqlQuery:    "SELECT * FROM sensitive_table",
+			userID:      2,
+			shouldAbort: true,
+		},
+		{
+			name:        "Non-admin accessing normal table",
+			sqlQuery:    "SELECT * FROM users",
+			userID:      2,
+			shouldAbort: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := &HookContext{
+				Context:  context.Background(),
+				SQLQuery: tt.sqlQuery,
+				UserContext: &security.UserContext{
+					UserID: tt.userID,
+				},
+			}
+
+			_ = ExampleSecurityHook(ctx)
+
+			if tt.shouldAbort {
+				if !ctx.Abort {
+					t.Error("Expected security hook to abort operation")
+				}
+				if ctx.AbortCode != 403 {
+					t.Errorf("Expected abort code 403, got %d", ctx.AbortCode)
+				}
+			} else {
+				if ctx.Abort {
+					t.Error("Expected security hook not to abort operation")
+				}
+			}
+		})
+	}
+}
+
+func TestExampleResultFilterHook(t *testing.T) {
+	tests := []struct {
+		name     string
+		userID   int
+		result   interface{}
+		validate func(t *testing.T, result interface{})
+	}{
+		{
+			name:   "Admin user - no filtering",
+			userID: 1,
+			result: map[string]interface{}{
+				"id":       1,
+				"name":     "Test",
+				"password": "secret",
+			},
+			validate: func(t *testing.T, result interface{}) {
+				m := result.(map[string]interface{})
+				if _, exists := m["password"]; !exists {
+					t.Error("Expected password field to remain for admin")
+				}
+			},
+		},
+		{
+			name:   "Regular user - sensitive fields removed",
+			userID: 2,
+			result: map[string]interface{}{
+				"id":       1,
+				"name":     "Test",
+				"password": "secret",
+				"ssn":      "123-45-6789",
+			},
+			validate: func(t *testing.T, result interface{}) {
+				m := result.(map[string]interface{})
+				if _, exists := m["password"]; exists {
+					t.Error("Expected password field to be removed")
+				}
+				if _, exists := m["ssn"]; exists {
+					t.Error("Expected ssn field to be removed")
+				}
+				if _, exists := m["name"]; !exists {
+					t.Error("Expected name field to remain")
+				}
+			},
+		},
+		{
+			name:   "Regular user - list results filtered",
+			userID: 2,
+			result: []map[string]interface{}{
+				{"id": 1, "name": "User 1", "password": "secret1"},
+				{"id": 2, "name": "User 2", "password": "secret2"},
+			},
+			validate: func(t *testing.T, result interface{}) {
+				list := result.([]map[string]interface{})
+				for _, m := range list {
+					if _, exists := m["password"]; exists {
+						t.Error("Expected password field to be removed from list")
+					}
+				}
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := &HookContext{
+				Context: context.Background(),
+				Result:  tt.result,
+				UserContext: &security.UserContext{
+					UserID: tt.userID,
+				},
+			}
+
+			err := ExampleResultFilterHook(ctx)
+			if err != nil {
+				t.Errorf("Hook failed: %v", err)
+			}
+
+			if tt.validate != nil {
+				tt.validate(t, ctx.Result)
+			}
+		})
+	}
+}
+
+func TestExampleAuditHook(t *testing.T) {
+	req := httptest.NewRequest("GET", "/api/test", nil)
+	req.RemoteAddr = "192.168.1.1:12345"
+
+	ctx := &HookContext{
+		Context: context.Background(),
+		Request: req,
+		UserContext: &security.UserContext{
+			UserID:   123,
+			UserName: "testuser",
+		},
+	}
+
+	err := ExampleAuditHook(ctx)
+	if err != nil {
+		t.Errorf("ExampleAuditHook failed: %v", err)
+	}
+}
+
+func TestExampleErrorHandlingHook(t *testing.T) {
+	ctx := &HookContext{
+		Context:  context.Background(),
+		SQLQuery: "SELECT * FROM test",
+		Error:    fmt.Errorf("test error"),
+		UserContext: &security.UserContext{
+			UserName: "testuser",
+		},
+	}
+
+	err := ExampleErrorHandlingHook(ctx)
+	if err != nil {
+		t.Errorf("ExampleErrorHandlingHook failed: %v", err)
+	}
+}
+
+// TestHookIntegrationWithHandler tests hooks integrated with the handler
+func TestHookIntegrationWithHandler(t *testing.T) {
+	db := &MockDatabase{
+		RunInTransactionFunc: func(ctx context.Context, fn func(common.Database) error) error {
+			queryDB := &MockDatabase{
+				QueryFunc: func(ctx context.Context, dest interface{}, query string, args ...interface{}) error {
+					rows := dest.(*[]map[string]interface{})
+					*rows = []map[string]interface{}{
+						{"id": float64(1), "name": "Test User"},
+					}
+					return nil
+				},
+			}
+			return fn(queryDB)
+		},
+	}
+
+	handler := NewHandler(db)
+
+	// Register a hook that modifies the SQL query
+	hookCalled := false
+	handler.Hooks().Register(BeforeSQLExec, func(ctx *HookContext) error {
+		hookCalled = true
+		// Verify we can access context data
+		if ctx.SQLQuery == "" {
+			t.Error("Expected SQL query to be set")
+		}
+		if ctx.UserContext == nil {
+			t.Error("Expected user context to be set")
+		}
+		return nil
+	})
+
+	// Execute a query
+	req := createTestRequest("GET", "/test", nil, nil, nil)
+	w := httptest.NewRecorder()
+
+	handlerFunc := handler.SqlQuery("SELECT * FROM users WHERE id = 1", false)
+	handlerFunc(w, req)
+
+	if !hookCalled {
+		t.Error("Expected hook to be called during query execution")
+	}
+
+	if w.Code != 200 {
+		t.Errorf("Expected status 200, got %d", w.Code)
+	}
+}

pkg/funcspec/parameters.go

@@ -0,0 +1,411 @@
+package funcspec
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
+	"github.com/bitechdev/ResolveSpec/pkg/restheadspec"
+)
+
+// RequestParameters holds parsed parameters from headers and query string
+type RequestParameters struct {
+	// Field selection
+	SelectFields    []string
+	NotSelectFields []string
+	Distinct        bool
+
+	// Filtering
+	FieldFilters   map[string]string         // column -> value (exact match)
+	SearchFilters  map[string]string         // column -> value (ILIKE)
+	SearchOps      map[string]FilterOperator // column -> {operator, value, logic}
+	CustomSQLWhere string
+	CustomSQLOr    string
+
+	// Sorting & Pagination
+	SortColumns string
+	Limit       int
+	Offset      int
+
+	// Advanced features
+	SkipCount bool
+	SkipCache bool
+
+	// Response format
+	ResponseFormat string // "simple", "detail", "syncfusion"
+	ComplexAPI     bool   // true if NOT simple API
+}
+
+// FilterOperator represents a filter with operator
+type FilterOperator struct {
+	Operator string // eq, neq, gt, lt, gte, lte, like, ilike, in, between, etc.
+	Value    string
+	Logic    string // AND or OR
+}
+
+// ParseParameters parses all parameters from request headers and query string
+func (h *Handler) ParseParameters(r *http.Request) *RequestParameters {
+	params := &RequestParameters{
+		FieldFilters:   make(map[string]string),
+		SearchFilters:  make(map[string]string),
+		SearchOps:      make(map[string]FilterOperator),
+		Limit:          20,       // Default limit
+		Offset:         0,        // Default offset
+		ResponseFormat: "simple", // Default format
+		ComplexAPI:     false,    // Default to simple API
+	}
+
+	// Merge headers and query parameters
+	combined := make(map[string]string)
+
+	// Add all headers (normalize to lowercase)
+	for key, values := range r.Header {
+		if len(values) > 0 {
+			combined[strings.ToLower(key)] = values[0]
+		}
+	}
+
+	// Add all query parameters (override headers)
+	for key, values := range r.URL.Query() {
+		if len(values) > 0 {
+			combined[strings.ToLower(key)] = values[0]
+		}
+	}
+
+	// Parse each parameter
+	for key, value := range combined {
+		// Decode value if base64 encoded
+		decodedValue := h.decodeValue(value)
+
+		switch {
+		// Field Selection
+		case strings.HasPrefix(key, "x-select-fields"):
+			params.SelectFields = h.parseCommaSeparated(decodedValue)
+		case strings.HasPrefix(key, "x-not-select-fields"):
+			params.NotSelectFields = h.parseCommaSeparated(decodedValue)
+		case strings.HasPrefix(key, "x-distinct"):
+			params.Distinct = strings.EqualFold(decodedValue, "true")
+
+		// Filtering
+		case strings.HasPrefix(key, "x-fieldfilter-"):
+			colName := strings.TrimPrefix(key, "x-fieldfilter-")
+			params.FieldFilters[colName] = decodedValue
+		case strings.HasPrefix(key, "x-searchfilter-"):
+			colName := strings.TrimPrefix(key, "x-searchfilter-")
+			params.SearchFilters[colName] = decodedValue
+		case strings.HasPrefix(key, "x-searchop-"):
+			h.parseSearchOp(params, key, decodedValue, "AND")
+		case strings.HasPrefix(key, "x-searchor-"):
+			h.parseSearchOp(params, key, decodedValue, "OR")
+		case strings.HasPrefix(key, "x-searchand-"):
+			h.parseSearchOp(params, key, decodedValue, "AND")
+		case strings.HasPrefix(key, "x-custom-sql-w"):
+			if params.CustomSQLWhere != "" {
+				params.CustomSQLWhere = fmt.Sprintf("%s AND (%s)", params.CustomSQLWhere, decodedValue)
+			} else {
+				params.CustomSQLWhere = decodedValue
+			}
+		case strings.HasPrefix(key, "x-custom-sql-or"):
+			if params.CustomSQLOr != "" {
+				params.CustomSQLOr = fmt.Sprintf("%s OR (%s)", params.CustomSQLOr, decodedValue)
+			} else {
+				params.CustomSQLOr = decodedValue
+			}
+
+		// Sorting & Pagination
+		case key == "sort" || strings.HasPrefix(key, "x-sort"):
+			params.SortColumns = decodedValue
+		case strings.HasPrefix(key, "sort(") && strings.Contains(key, ")"):
+			// Handle sort(col1,-col2) syntax
+			sortValue := key[strings.Index(key, "(")+1 : strings.Index(key, ")")]
+			params.SortColumns = sortValue
+		case key == "limit" || strings.HasPrefix(key, "x-limit"):
+			if limit, err := strconv.Atoi(decodedValue); err == nil && limit > 0 {
+				params.Limit = limit
+			}
+		case strings.HasPrefix(key, "limit(") && strings.Contains(key, ")"):
+			// Handle limit(offset,limit) or limit(limit) syntax
+			limitValue := key[strings.Index(key, "(")+1 : strings.Index(key, ")")]
+			parts := strings.Split(limitValue, ",")
+			if len(parts) > 1 {
+				if offset, err := strconv.Atoi(parts[0]); err == nil {
+					params.Offset = offset
+				}
+				if limit, err := strconv.Atoi(parts[1]); err == nil {
+					params.Limit = limit
+				}
+			} else {
+				if limit, err := strconv.Atoi(parts[0]); err == nil {
+					params.Limit = limit
+				}
+			}
+		case key == "offset" || strings.HasPrefix(key, "x-offset"):
+			if offset, err := strconv.Atoi(decodedValue); err == nil && offset >= 0 {
+				params.Offset = offset
+			}
+
+		// Advanced features
+		case strings.HasPrefix(key, "x-skipcount"):
+			params.SkipCount = strings.EqualFold(decodedValue, "true")
+		case strings.HasPrefix(key, "x-skipcache"):
+			params.SkipCache = strings.EqualFold(decodedValue, "true")
+
+		// Response Format
+		case strings.HasPrefix(key, "x-simpleapi"):
+			params.ResponseFormat = "simple"
+			params.ComplexAPI = decodedValue != "1" && !strings.EqualFold(decodedValue, "true")
+		case strings.HasPrefix(key, "x-detailapi"):
+			params.ResponseFormat = "detail"
+			params.ComplexAPI = true
+		case strings.HasPrefix(key, "x-syncfusion"):
+			params.ResponseFormat = "syncfusion"
+			params.ComplexAPI = true
+		}
+	}
+
+	return params
+}
+
+// parseSearchOp parses x-searchop-{operator}-{column} or x-searchor-{operator}-{column}
+func (h *Handler) parseSearchOp(params *RequestParameters, headerKey, value, logic string) {
+	var prefix string
+	if logic == "OR" {
+		prefix = "x-searchor-"
+	} else {
+		prefix = "x-searchop-"
+		if strings.HasPrefix(headerKey, "x-searchand-") {
+			prefix = "x-searchand-"
+		}
+	}
+
+	rest := strings.TrimPrefix(headerKey, prefix)
+	parts := strings.SplitN(rest, "-", 2)
+	if len(parts) != 2 {
+		logger.Warn("Invalid search operator header format: %s", headerKey)
+		return
+	}
+
+	operator := parts[0]
+	colName := parts[1]
+
+	params.SearchOps[colName] = FilterOperator{
+		Operator: operator,
+		Value:    value,
+		Logic:    logic,
+	}
+
+	logger.Debug("%s search operator: %s %s %s", logic, colName, operator, value)
+}
+
+// decodeValue decodes base64 encoded values (ZIP_ or __ prefix)
+func (h *Handler) decodeValue(value string) string {
+	decoded, _ := restheadspec.DecodeParam(value)
+	return decoded
+}
+
+// parseCommaSeparated parses comma-separated values
+func (h *Handler) parseCommaSeparated(value string) []string {
+	if value == "" {
+		return nil
+	}
+
+	parts := strings.Split(value, ",")
+	result := make([]string, 0, len(parts))
+	for _, part := range parts {
+		part = strings.TrimSpace(part)
+		if part != "" {
+			result = append(result, part)
+		}
+	}
+	return result
+}
+
+// ApplyFieldSelection applies column selection to SQL query
+func (h *Handler) ApplyFieldSelection(sqlQuery string, params *RequestParameters) string {
+	if len(params.SelectFields) == 0 && len(params.NotSelectFields) == 0 {
+		return sqlQuery
+	}
+
+	// This is a simplified implementation
+	// A full implementation would parse the SQL and replace the SELECT clause
+	// For now, we log a warning that this feature needs manual implementation
+	if len(params.SelectFields) > 0 {
+		logger.Debug("Field selection requested: %v (manual SQL adjustment may be needed)", params.SelectFields)
+	}
+	if len(params.NotSelectFields) > 0 {
+		logger.Debug("Field exclusion requested: %v (manual SQL adjustment may be needed)", params.NotSelectFields)
+	}
+
+	return sqlQuery
+}
+
+// ApplyFilters applies all filters to the SQL query
+func (h *Handler) ApplyFilters(sqlQuery string, params *RequestParameters) string {
+	// Apply field filters (exact match)
+	for colName, value := range params.FieldFilters {
+		condition := ""
+		if value == "" || value == "0" {
+			condition = fmt.Sprintf("COALESCE(%s, 0) = %s", ValidSQL(colName, "colname"), ValidSQL(value, "colvalue"))
+		} else {
+			condition = fmt.Sprintf("%s = %s", ValidSQL(colName, "colname"), ValidSQL(value, "colvalue"))
+		}
+		sqlQuery = sqlQryWhere(sqlQuery, condition)
+		logger.Debug("Applied field filter: %s", condition)
+	}
+
+	// Apply search filters (ILIKE)
+	for colName, value := range params.SearchFilters {
+		sval := strings.ReplaceAll(value, "'", "")
+		if sval != "" {
+			condition := fmt.Sprintf("%s ILIKE '%%%s%%'", ValidSQL(colName, "colname"), ValidSQL(sval, "colvalue"))
+			sqlQuery = sqlQryWhere(sqlQuery, condition)
+			logger.Debug("Applied search filter: %s", condition)
+		}
+	}
+
+	// Apply search operators
+	for colName, filterOp := range params.SearchOps {
+		condition := h.buildFilterCondition(colName, filterOp)
+		if condition != "" {
+			if filterOp.Logic == "OR" {
+				sqlQuery = sqlQryWhereOr(sqlQuery, condition)
+			} else {
+				sqlQuery = sqlQryWhere(sqlQuery, condition)
+			}
+			logger.Debug("Applied search operator: %s", condition)
+		}
+	}
+
+	// Apply custom SQL WHERE
+	if params.CustomSQLWhere != "" {
+		colval := ValidSQL(params.CustomSQLWhere, "select")
+		if colval != "" {
+			sqlQuery = sqlQryWhere(sqlQuery, colval)
+			logger.Debug("Applied custom SQL WHERE: %s", colval)
+		}
+	}
+
+	// Apply custom SQL OR
+	if params.CustomSQLOr != "" {
+		colval := ValidSQL(params.CustomSQLOr, "select")
+		if colval != "" {
+			sqlQuery = sqlQryWhereOr(sqlQuery, colval)
+			logger.Debug("Applied custom SQL OR: %s", colval)
+		}
+	}
+
+	return sqlQuery
+}
+
+// buildFilterCondition builds a SQL condition from a FilterOperator
+func (h *Handler) buildFilterCondition(colName string, op FilterOperator) string {
+	safCol := ValidSQL(colName, "colname")
+	operator := strings.ToLower(op.Operator)
+	value := op.Value
+
+	switch operator {
+	case "contains", "contain", "like":
+		return fmt.Sprintf("%s ILIKE '%%%s%%'", safCol, ValidSQL(value, "colvalue"))
+	case "beginswith", "startswith":
+		return fmt.Sprintf("%s ILIKE '%s%%'", safCol, ValidSQL(value, "colvalue"))
+	case "endswith":
+		return fmt.Sprintf("%s ILIKE '%%%s'", safCol, ValidSQL(value, "colvalue"))
+	case "equals", "eq", "=":
+		if IsNumeric(value) {
+			return fmt.Sprintf("%s = %s", safCol, ValidSQL(value, "colvalue"))
+		}
+		return fmt.Sprintf("%s = '%s'", safCol, ValidSQL(value, "colvalue"))
+	case "notequals", "neq", "ne", "!=", "<>":
+		if IsNumeric(value) {
+			return fmt.Sprintf("%s != %s", safCol, ValidSQL(value, "colvalue"))
+		}
+		return fmt.Sprintf("%s != '%s'", safCol, ValidSQL(value, "colvalue"))
+	case "greaterthan", "gt", ">":
+		return fmt.Sprintf("%s > %s", safCol, ValidSQL(value, "colvalue"))
+	case "lessthan", "lt", "<":
+		return fmt.Sprintf("%s < %s", safCol, ValidSQL(value, "colvalue"))
+	case "greaterthanorequal", "gte", "ge", ">=":
+		return fmt.Sprintf("%s >= %s", safCol, ValidSQL(value, "colvalue"))
+	case "lessthanorequal", "lte", "le", "<=":
+		return fmt.Sprintf("%s <= %s", safCol, ValidSQL(value, "colvalue"))
+	case "between":
+		parts := strings.Split(value, ",")
+		if len(parts) == 2 {
+			return fmt.Sprintf("%s > %s AND %s < %s", safCol, ValidSQL(parts[0], "colvalue"), safCol, ValidSQL(parts[1], "colvalue"))
+		}
+	case "betweeninclusive":
+		parts := strings.Split(value, ",")
+		if len(parts) == 2 {
+			return fmt.Sprintf("%s >= %s AND %s <= %s", safCol, ValidSQL(parts[0], "colvalue"), safCol, ValidSQL(parts[1], "colvalue"))
+		}
+	case "in":
+		values := strings.Split(value, ",")
+		safeValues := make([]string, len(values))
+		for i, v := range values {
+			safeValues[i] = fmt.Sprintf("'%s'", ValidSQL(v, "colvalue"))
+		}
+		return fmt.Sprintf("%s IN (%s)", safCol, strings.Join(safeValues, ", "))
+	case "empty", "isnull", "null":
+		return fmt.Sprintf("(%s IS NULL OR %s = '')", safCol, safCol)
+	case "notempty", "isnotnull", "notnull":
+		return fmt.Sprintf("(%s IS NOT NULL AND %s != '')", safCol, safCol)
+	default:
+		logger.Warn("Unknown filter operator: %s, defaulting to equals", operator)
+		return fmt.Sprintf("%s = '%s'", safCol, ValidSQL(value, "colvalue"))
+	}
+
+	return ""
+}
+
+// ApplyDistinct adds DISTINCT to SQL query if requested
+func (h *Handler) ApplyDistinct(sqlQuery string, params *RequestParameters) string {
+	if !params.Distinct {
+		return sqlQuery
+	}
+
+	// Add DISTINCT after SELECT
+	selectPos := strings.Index(strings.ToUpper(sqlQuery), "SELECT")
+	if selectPos >= 0 {
+		beforeSelect := sqlQuery[:selectPos+6] // "SELECT"
+		afterSelect := sqlQuery[selectPos+6:]
+		sqlQuery = beforeSelect + " DISTINCT" + afterSelect
+		logger.Debug("Applied DISTINCT to query")
+	}
+
+	return sqlQuery
+}
+
+// sqlQryWhereOr adds a WHERE clause with OR logic
+func sqlQryWhereOr(sqlquery, condition string) string {
+	lowerQuery := strings.ToLower(sqlquery)
+	wherePos := strings.Index(lowerQuery, " where ")
+	groupPos := strings.Index(lowerQuery, " group by")
+	orderPos := strings.Index(lowerQuery, " order by")
+	limitPos := strings.Index(lowerQuery, " limit ")
+
+	// Find the insertion point
+	insertPos := len(sqlquery)
+	if groupPos > 0 && groupPos < insertPos {
+		insertPos = groupPos
+	}
+	if orderPos > 0 && orderPos < insertPos {
+		insertPos = orderPos
+	}
+	if limitPos > 0 && limitPos < insertPos {
+		insertPos = limitPos
+	}
+
+	if wherePos > 0 {
+		// WHERE exists, add OR condition
+		before := sqlquery[:insertPos]
+		after := sqlquery[insertPos:]
+		return fmt.Sprintf("%s OR (%s) %s", before, condition, after)
+	} else {
+		// No WHERE exists, add it
+		before := sqlquery[:insertPos]
+		after := sqlquery[insertPos:]
+		return fmt.Sprintf("%s WHERE %s %s", before, condition, after)
+	}
+}

pkg/funcspec/parameters_test.go

@@ -0,0 +1,549 @@
+package funcspec
+
+import (
+	"strings"
+	"testing"
+)
+
+// TestParseParameters tests the comprehensive parameter parsing
+func TestParseParameters(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+
+	tests := []struct {
+		name        string
+		queryParams map[string]string
+		headers     map[string]string
+		validate    func(t *testing.T, params *RequestParameters)
+	}{
+		{
+			name: "Parse field selection",
+			headers: map[string]string{
+				"X-Select-Fields":     "id,name,email",
+				"X-Not-Select-Fields": "password,ssn",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if len(params.SelectFields) != 3 {
+					t.Errorf("Expected 3 select fields, got %d", len(params.SelectFields))
+				}
+				if len(params.NotSelectFields) != 2 {
+					t.Errorf("Expected 2 not-select fields, got %d", len(params.NotSelectFields))
+				}
+			},
+		},
+		{
+			name: "Parse distinct flag",
+			headers: map[string]string{
+				"X-Distinct": "true",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if !params.Distinct {
+					t.Error("Expected Distinct to be true")
+				}
+			},
+		},
+		{
+			name: "Parse field filters",
+			headers: map[string]string{
+				"X-FieldFilter-Status": "active",
+				"X-FieldFilter-Type":   "admin",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if len(params.FieldFilters) != 2 {
+					t.Errorf("Expected 2 field filters, got %d", len(params.FieldFilters))
+				}
+				if params.FieldFilters["status"] != "active" {
+					t.Errorf("Expected status filter=active, got %s", params.FieldFilters["status"])
+				}
+			},
+		},
+		{
+			name: "Parse search filters",
+			headers: map[string]string{
+				"X-SearchFilter-Name":  "john",
+				"X-SearchFilter-Email": "test",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if len(params.SearchFilters) != 2 {
+					t.Errorf("Expected 2 search filters, got %d", len(params.SearchFilters))
+				}
+			},
+		},
+		{
+			name: "Parse sort columns",
+			queryParams: map[string]string{
+				"sort": "-created_at,name",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if params.SortColumns != "-created_at,name" {
+					t.Errorf("Expected sort columns=-created_at,name, got %s", params.SortColumns)
+				}
+			},
+		},
+		{
+			name: "Parse limit and offset",
+			queryParams: map[string]string{
+				"limit":  "100",
+				"offset": "50",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if params.Limit != 100 {
+					t.Errorf("Expected limit=100, got %d", params.Limit)
+				}
+				if params.Offset != 50 {
+					t.Errorf("Expected offset=50, got %d", params.Offset)
+				}
+			},
+		},
+		{
+			name: "Parse skip count",
+			headers: map[string]string{
+				"X-SkipCount": "true",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if !params.SkipCount {
+					t.Error("Expected SkipCount to be true")
+				}
+			},
+		},
+		{
+			name: "Parse response format - syncfusion",
+			headers: map[string]string{
+				"X-Syncfusion": "true",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if params.ResponseFormat != "syncfusion" {
+					t.Errorf("Expected ResponseFormat=syncfusion, got %s", params.ResponseFormat)
+				}
+				if !params.ComplexAPI {
+					t.Error("Expected ComplexAPI to be true for syncfusion format")
+				}
+			},
+		},
+		{
+			name: "Parse response format - detail",
+			headers: map[string]string{
+				"X-DetailAPI": "true",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if params.ResponseFormat != "detail" {
+					t.Errorf("Expected ResponseFormat=detail, got %s", params.ResponseFormat)
+				}
+			},
+		},
+		{
+			name: "Parse simple API",
+			headers: map[string]string{
+				"X-SimpleAPI": "true",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if params.ResponseFormat != "simple" {
+					t.Errorf("Expected ResponseFormat=simple, got %s", params.ResponseFormat)
+				}
+				if params.ComplexAPI {
+					t.Error("Expected ComplexAPI to be false for simple API")
+				}
+			},
+		},
+		{
+			name: "Parse custom SQL WHERE",
+			headers: map[string]string{
+				"X-Custom-SQL-W": "status = 'active' AND deleted = false",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if params.CustomSQLWhere == "" {
+					t.Error("Expected CustomSQLWhere to be set")
+				}
+			},
+		},
+		{
+			name: "Parse search operators - AND",
+			headers: map[string]string{
+				"X-SearchOp-Eq-Name":  "john",
+				"X-SearchOp-Gt-Age":   "18",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if len(params.SearchOps) != 2 {
+					t.Errorf("Expected 2 search operators, got %d", len(params.SearchOps))
+				}
+				if op, exists := params.SearchOps["name"]; exists {
+					if op.Operator != "eq" {
+						t.Errorf("Expected operator=eq for name, got %s", op.Operator)
+					}
+					if op.Logic != "AND" {
+						t.Errorf("Expected logic=AND, got %s", op.Logic)
+					}
+				} else {
+					t.Error("Expected name search operator to exist")
+				}
+			},
+		},
+		{
+			name: "Parse search operators - OR",
+			headers: map[string]string{
+				"X-SearchOr-Like-Description": "test",
+			},
+			validate: func(t *testing.T, params *RequestParameters) {
+				if op, exists := params.SearchOps["description"]; exists {
+					if op.Logic != "OR" {
+						t.Errorf("Expected logic=OR, got %s", op.Logic)
+					}
+				} else {
+					t.Error("Expected description search operator to exist")
+				}
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := createTestRequest("GET", "/test", tt.queryParams, tt.headers, nil)
+			params := handler.ParseParameters(req)
+
+			if tt.validate != nil {
+				tt.validate(t, params)
+			}
+		})
+	}
+}
+
+// TestBuildFilterCondition tests the filter condition builder
+func TestBuildFilterCondition(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+
+	tests := []struct {
+		name      string
+		colName   string
+		operator  FilterOperator
+		expected  string
+	}{
+		{
+			name:    "Equals operator - numeric",
+			colName: "age",
+			operator: FilterOperator{
+				Operator: "eq",
+				Value:    "25",
+				Logic:    "AND",
+			},
+			expected: "age = 25",
+		},
+		{
+			name:    "Equals operator - string",
+			colName: "name",
+			operator: FilterOperator{
+				Operator: "eq",
+				Value:    "john",
+				Logic:    "AND",
+			},
+			expected: "name = 'john'",
+		},
+		{
+			name:    "Not equals operator",
+			colName: "status",
+			operator: FilterOperator{
+				Operator: "neq",
+				Value:    "inactive",
+				Logic:    "AND",
+			},
+			expected: "status != 'inactive'",
+		},
+		{
+			name:    "Greater than operator",
+			colName: "age",
+			operator: FilterOperator{
+				Operator: "gt",
+				Value:    "18",
+				Logic:    "AND",
+			},
+			expected: "age > 18",
+		},
+		{
+			name:    "Less than operator",
+			colName: "price",
+			operator: FilterOperator{
+				Operator: "lt",
+				Value:    "100",
+				Logic:    "AND",
+			},
+			expected: "price < 100",
+		},
+		{
+			name:    "Contains operator",
+			colName: "description",
+			operator: FilterOperator{
+				Operator: "contains",
+				Value:    "test",
+				Logic:    "AND",
+			},
+			expected: "description ILIKE '%test%'",
+		},
+		{
+			name:    "Starts with operator",
+			colName: "name",
+			operator: FilterOperator{
+				Operator: "startswith",
+				Value:    "john",
+				Logic:    "AND",
+			},
+			expected: "name ILIKE 'john%'",
+		},
+		{
+			name:    "Ends with operator",
+			colName: "email",
+			operator: FilterOperator{
+				Operator: "endswith",
+				Value:    "@example.com",
+				Logic:    "AND",
+			},
+			expected: "email ILIKE '%@example.com'",
+		},
+		{
+			name:    "Between operator",
+			colName: "age",
+			operator: FilterOperator{
+				Operator: "between",
+				Value:    "18,65",
+				Logic:    "AND",
+			},
+			expected: "age > 18 AND age < 65",
+		},
+		{
+			name:    "IN operator",
+			colName: "status",
+			operator: FilterOperator{
+				Operator: "in",
+				Value:    "active,pending,approved",
+				Logic:    "AND",
+			},
+			expected: "status IN ('active', 'pending', 'approved')",
+		},
+		{
+			name:    "IS NULL operator",
+			colName: "deleted_at",
+			operator: FilterOperator{
+				Operator: "null",
+				Value:    "",
+				Logic:    "AND",
+			},
+			expected: "(deleted_at IS NULL OR deleted_at = '')",
+		},
+		{
+			name:    "IS NOT NULL operator",
+			colName: "created_at",
+			operator: FilterOperator{
+				Operator: "notnull",
+				Value:    "",
+				Logic:    "AND",
+			},
+			expected: "(created_at IS NOT NULL AND created_at != '')",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := handler.buildFilterCondition(tt.colName, tt.operator)
+			if result != tt.expected {
+				t.Errorf("Expected: %s\nGot: %s", tt.expected, result)
+			}
+		})
+	}
+}
+
+// TestApplyFilters tests the filter application to SQL queries
+func TestApplyFilters(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+
+	tests := []struct {
+		name         string
+		sqlQuery     string
+		params       *RequestParameters
+		expectedSQL  string
+		shouldContain []string
+	}{
+		{
+			name:     "Apply field filter",
+			sqlQuery: "SELECT * FROM users",
+			params: &RequestParameters{
+				FieldFilters: map[string]string{
+					"status": "active",
+				},
+			},
+			shouldContain: []string{"WHERE", "status"},
+		},
+		{
+			name:     "Apply search filter",
+			sqlQuery: "SELECT * FROM users",
+			params: &RequestParameters{
+				SearchFilters: map[string]string{
+					"name": "john",
+				},
+			},
+			shouldContain: []string{"WHERE", "name", "ILIKE"},
+		},
+		{
+			name:     "Apply search operators",
+			sqlQuery: "SELECT * FROM users",
+			params: &RequestParameters{
+				SearchOps: map[string]FilterOperator{
+					"age": {
+						Operator: "gt",
+						Value:    "18",
+						Logic:    "AND",
+					},
+				},
+			},
+			shouldContain: []string{"WHERE", "age", ">", "18"},
+		},
+		{
+			name:     "Apply custom SQL WHERE",
+			sqlQuery: "SELECT * FROM users",
+			params: &RequestParameters{
+				CustomSQLWhere: "deleted = false",
+			},
+			shouldContain: []string{"WHERE", "deleted"},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := handler.ApplyFilters(tt.sqlQuery, tt.params)
+
+			for _, expected := range tt.shouldContain {
+				if !strings.Contains(result, expected) {
+					t.Errorf("Expected SQL to contain %q, got: %s", expected, result)
+				}
+			}
+		})
+	}
+}
+
+// TestApplyDistinct tests DISTINCT application
+func TestApplyDistinct(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+
+	tests := []struct {
+		name        string
+		sqlQuery    string
+		distinct    bool
+		shouldHave  string
+	}{
+		{
+			name:       "Apply DISTINCT",
+			sqlQuery:   "SELECT id, name FROM users",
+			distinct:   true,
+			shouldHave: "SELECT DISTINCT",
+		},
+		{
+			name:       "Do not apply DISTINCT",
+			sqlQuery:   "SELECT id, name FROM users",
+			distinct:   false,
+			shouldHave: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			params := &RequestParameters{Distinct: tt.distinct}
+			result := handler.ApplyDistinct(tt.sqlQuery, params)
+
+			if tt.shouldHave != "" {
+				if !strings.Contains(result, tt.shouldHave) {
+					t.Errorf("Expected SQL to contain %q, got: %s", tt.shouldHave, result)
+				}
+			} else {
+				// Should not have DISTINCT when not requested
+				if strings.Contains(result, "DISTINCT") && !tt.distinct {
+					t.Errorf("SQL should not contain DISTINCT when not requested: %s", result)
+				}
+			}
+		})
+	}
+}
+
+// TestParseCommaSeparated tests comma-separated value parsing
+func TestParseCommaSeparated(t *testing.T) {
+	handler := NewHandler(&MockDatabase{})
+
+	tests := []struct {
+		name     string
+		input    string
+		expected []string
+	}{
+		{
+			name:     "Simple comma-separated",
+			input:    "id,name,email",
+			expected: []string{"id", "name", "email"},
+		},
+		{
+			name:     "With spaces",
+			input:    "id, name, email",
+			expected: []string{"id", "name", "email"},
+		},
+		{
+			name:     "Empty string",
+			input:    "",
+			expected: nil,
+		},
+		{
+			name:     "Single value",
+			input:    "id",
+			expected: []string{"id"},
+		},
+		{
+			name:     "With extra commas",
+			input:    "id,,name,,email",
+			expected: []string{"id", "name", "email"},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := handler.parseCommaSeparated(tt.input)
+
+			if len(result) != len(tt.expected) {
+				t.Errorf("Expected %d values, got %d", len(tt.expected), len(result))
+				return
+			}
+
+			for i, expected := range tt.expected {
+				if result[i] != expected {
+					t.Errorf("Expected value %d to be %s, got %s", i, expected, result[i])
+				}
+			}
+		})
+	}
+}
+
+// TestSqlQryWhereOr tests OR WHERE clause manipulation
+func TestSqlQryWhereOr(t *testing.T) {
+	tests := []struct {
+		name          string
+		sqlQuery      string
+		condition     string
+		shouldContain []string
+	}{
+		{
+			name:          "Add WHERE with OR to query without WHERE",
+			sqlQuery:      "SELECT * FROM users",
+			condition:     "status = 'inactive'",
+			shouldContain: []string{"WHERE", "status = 'inactive'"},
+		},
+		{
+			name:          "Add OR to query with existing WHERE",
+			sqlQuery:      "SELECT * FROM users WHERE id > 0",
+			condition:     "status = 'inactive'",
+			shouldContain: []string{"WHERE", "OR", "(status = 'inactive')"},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := sqlQryWhereOr(tt.sqlQuery, tt.condition)
+
+			for _, expected := range tt.shouldContain {
+				if !strings.Contains(result, expected) {
+					t.Errorf("Expected SQL to contain %q, got: %s", expected, result)
+				}
+			}
+		})
+	}
+}

pkg/funcspec/security_adapter.go

@@ -0,0 +1,83 @@
+package funcspec
+
+import (
+	"context"
+
+	"github.com/bitechdev/ResolveSpec/pkg/security"
+)
+
+// RegisterSecurityHooks registers security hooks for funcspec handlers
+// Note: funcspec operates on SQL queries directly, so row-level security is not directly applicable
+// We provide audit logging for data access tracking
+func RegisterSecurityHooks(handler *Handler, securityList *security.SecurityList) {
+	// Hook 1: BeforeQueryList - Audit logging before query list execution
+	handler.Hooks().Register(BeforeQueryList, func(hookCtx *HookContext) error {
+		secCtx := newFuncSpecSecurityContext(hookCtx)
+		return security.LogDataAccess(secCtx)
+	})
+
+	// Hook 2: BeforeQuery - Audit logging before single query execution
+	handler.Hooks().Register(BeforeQuery, func(hookCtx *HookContext) error {
+		secCtx := newFuncSpecSecurityContext(hookCtx)
+		return security.LogDataAccess(secCtx)
+	})
+
+	// Note: Row-level security and column masking are challenging in funcspec
+	// because the SQL query is fully user-defined. Security should be implemented
+	// at the SQL function level or through database policies (RLS).
+}
+
+// funcSpecSecurityContext adapts funcspec.HookContext to security.SecurityContext interface
+type funcSpecSecurityContext struct {
+	ctx *HookContext
+}
+
+func newFuncSpecSecurityContext(ctx *HookContext) security.SecurityContext {
+	return &funcSpecSecurityContext{ctx: ctx}
+}
+
+func (f *funcSpecSecurityContext) GetContext() context.Context {
+	return f.ctx.Context
+}
+
+func (f *funcSpecSecurityContext) GetUserID() (int, bool) {
+	if f.ctx.UserContext == nil {
+		return 0, false
+	}
+	return int(f.ctx.UserContext.UserID), true
+}
+
+func (f *funcSpecSecurityContext) GetSchema() string {
+	// funcspec doesn't have a schema concept, extract from SQL query or use default
+	return "public"
+}
+
+func (f *funcSpecSecurityContext) GetEntity() string {
+	// funcspec doesn't have an entity concept, could parse from SQL or use a placeholder
+	return "sql_query"
+}
+
+func (f *funcSpecSecurityContext) GetModel() interface{} {
+	// funcspec doesn't use models in the same way as restheadspec
+	return nil
+}
+
+func (f *funcSpecSecurityContext) GetQuery() interface{} {
+	// In funcspec, the query is a string, not a query builder object
+	return f.ctx.SQLQuery
+}
+
+func (f *funcSpecSecurityContext) SetQuery(query interface{}) {
+	// In funcspec, we could modify the SQL string, but this should be done cautiously
+	if sqlQuery, ok := query.(string); ok {
+		f.ctx.SQLQuery = sqlQuery
+	}
+}
+
+func (f *funcSpecSecurityContext) GetResult() interface{} {
+	return f.ctx.Result
+}
+
+func (f *funcSpecSecurityContext) SetResult(result interface{}) {
+	f.ctx.Result = result
+}

pkg/logger/logger.go

@@ -23,6 +23,15 @@ func Init(dev bool) {
 
 }
 
+func UpdateLoggerPath(path string, dev bool) {
+	defaultConfig := zap.NewProductionConfig()
+	if dev {
+		defaultConfig = zap.NewDevelopmentConfig()
+	}
+	defaultConfig.OutputPaths = []string{path}
+	UpdateLogger(&defaultConfig)
+}
+
 func UpdateLogger(config *zap.Config) {
 	defaultConfig := zap.NewProductionConfig()
 	defaultConfig.OutputPaths = []string{"resolvespec.log"}
@@ -103,3 +112,18 @@ func CatchPanicCallback(location string, cb func(err any)) {
 func CatchPanic(location string) {
 	CatchPanicCallback(location, nil)
 }
+
+// HandlePanic logs a panic and returns it as an error
+// This should be called with the result of recover() from a deferred function
+// Example usage:
+//
+//	defer func() {
+//	    if r := recover(); r != nil {
+//	        err = logger.HandlePanic("MethodName", r)
+//	    }
+//	}()
+func HandlePanic(methodName string, r any) error {
+	stack := debug.Stack()
+	Error("Panic in %s: %v\nStack trace:\n%s", methodName, r, string(stack))
+	return fmt.Errorf("panic in %s: %v", methodName, r)
+}

pkg/metrics/README.md

@@ -0,0 +1,259 @@
+# Metrics Package
+
+A pluggable metrics collection system with Prometheus implementation.
+
+## Quick Start
+
+```go
+import "github.com/bitechdev/ResolveSpec/pkg/metrics"
+
+// Initialize Prometheus provider
+provider := metrics.NewPrometheusProvider()
+metrics.SetProvider(provider)
+
+// Apply middleware to your router
+router.Use(provider.Middleware)
+
+// Expose metrics endpoint
+http.Handle("/metrics", provider.Handler())
+```
+
+## Provider Interface
+
+The package uses a provider interface, allowing you to plug in different metric systems:
+
+```go
+type Provider interface {
+    RecordHTTPRequest(method, path, status string, duration time.Duration)
+    IncRequestsInFlight()
+    DecRequestsInFlight()
+    RecordDBQuery(operation, table string, duration time.Duration, err error)
+    RecordCacheHit(provider string)
+    RecordCacheMiss(provider string)
+    UpdateCacheSize(provider string, size int64)
+    Handler() http.Handler
+}
+```
+
+## Recording Metrics
+
+### HTTP Metrics (Automatic)
+
+When using the middleware, HTTP metrics are recorded automatically:
+
+```go
+router.Use(provider.Middleware)
+```
+
+**Collected:**
+- Request duration (histogram)
+- Request count by method, path, and status
+- Requests in flight (gauge)
+
+### Database Metrics
+
+```go
+start := time.Now()
+rows, err := db.Query("SELECT * FROM users WHERE id = ?", userID)
+duration := time.Since(start)
+
+metrics.GetProvider().RecordDBQuery("SELECT", "users", duration, err)
+```
+
+### Cache Metrics
+
+```go
+// Record cache hit
+metrics.GetProvider().RecordCacheHit("memory")
+
+// Record cache miss
+metrics.GetProvider().RecordCacheMiss("memory")
+
+// Update cache size
+metrics.GetProvider().UpdateCacheSize("memory", 1024)
+```
+
+## Prometheus Metrics
+
+When using `PrometheusProvider`, the following metrics are available:
+
+| Metric Name | Type | Labels | Description |
+|-------------|------|--------|-------------|
+| `http_request_duration_seconds` | Histogram | method, path, status | HTTP request duration |
+| `http_requests_total` | Counter | method, path, status | Total HTTP requests |
+| `http_requests_in_flight` | Gauge | - | Current in-flight requests |
+| `db_query_duration_seconds` | Histogram | operation, table | Database query duration |
+| `db_queries_total` | Counter | operation, table, status | Total database queries |
+| `cache_hits_total` | Counter | provider | Total cache hits |
+| `cache_misses_total` | Counter | provider | Total cache misses |
+| `cache_size_items` | Gauge | provider | Current cache size |
+
+## Prometheus Queries
+
+### HTTP Request Rate
+
+```promql
+rate(http_requests_total[5m])
+```
+
+### HTTP Request Duration (95th percentile)
+
+```promql
+histogram_quantile(0.95, rate(http_request_duration_seconds_bucket[5m]))
+```
+
+### Database Query Error Rate
+
+```promql
+rate(db_queries_total{status="error"}[5m])
+```
+
+### Cache Hit Rate
+
+```promql
+rate(cache_hits_total[5m]) / (rate(cache_hits_total[5m]) + rate(cache_misses_total[5m]))
+```
+
+## No-Op Provider
+
+If metrics are disabled:
+
+```go
+// No provider set - uses no-op provider automatically
+metrics.GetProvider().RecordHTTPRequest(...) // Does nothing
+```
+
+## Custom Provider
+
+Implement your own metrics provider:
+
+```go
+type CustomProvider struct{}
+
+func (c *CustomProvider) RecordHTTPRequest(method, path, status string, duration time.Duration) {
+    // Send to your metrics system
+}
+
+// Implement other Provider interface methods...
+
+func (c *CustomProvider) Handler() http.Handler {
+    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+        // Return your metrics format
+    })
+}
+
+// Use it
+metrics.SetProvider(&CustomProvider{})
+```
+
+## Complete Example
+
+```go
+package main
+
+import (
+    "database/sql"
+    "log"
+    "net/http"
+    "time"
+
+    "github.com/bitechdev/ResolveSpec/pkg/metrics"
+    "github.com/gorilla/mux"
+)
+
+func main() {
+    // Initialize metrics
+    provider := metrics.NewPrometheusProvider()
+    metrics.SetProvider(provider)
+
+    // Create router
+    router := mux.NewRouter()
+
+    // Apply metrics middleware
+    router.Use(provider.Middleware)
+
+    // Expose metrics endpoint
+    router.Handle("/metrics", provider.Handler())
+
+    // Your API routes
+    router.HandleFunc("/api/users", getUsersHandler)
+
+    log.Fatal(http.ListenAndServe(":8080", router))
+}
+
+func getUsersHandler(w http.ResponseWriter, r *http.Request) {
+    // Record database query
+    start := time.Now()
+    users, err := fetchUsers()
+    duration := time.Since(start)
+
+    metrics.GetProvider().RecordDBQuery("SELECT", "users", duration, err)
+
+    if err != nil {
+        http.Error(w, "Internal Server Error", 500)
+        return
+    }
+
+    // Return users...
+}
+```
+
+## Docker Compose Example
+
+```yaml
+version: '3'
+services:
+  app:
+    build: .
+    ports:
+      - "8080:8080"
+
+  prometheus:
+    image: prom/prometheus
+    ports:
+      - "9090:9090"
+    volumes:
+      - ./prometheus.yml:/etc/prometheus/prometheus.yml
+    command:
+      - '--config.file=/etc/prometheus/prometheus.yml'
+
+  grafana:
+    image: grafana/grafana
+    ports:
+      - "3000:3000"
+    depends_on:
+      - prometheus
+```
+
+**prometheus.yml:**
+
+```yaml
+global:
+  scrape_interval: 15s
+
+scrape_configs:
+  - job_name: 'resolvespec'
+    static_configs:
+      - targets: ['app:8080']
+```
+
+## Best Practices
+
+1. **Label Cardinality**: Keep labels low-cardinality
+   - ✅ Good: `method`, `status_code`
+   - ❌ Bad: `user_id`, `timestamp`
+
+2. **Path Normalization**: Normalize dynamic paths
+   ```go
+   // Instead of /api/users/123
+   // Use /api/users/:id
+   ```
+
+3. **Metric Naming**: Follow Prometheus conventions
+   - Use `_total` suffix for counters
+   - Use `_seconds` suffix for durations
+   - Use base units (seconds, not milliseconds)
+
+4. **Performance**: Metrics collection is lock-free and highly performant
+   - Safe for high-throughput applications
+   - Minimal overhead (<1% in most cases)

pkg/metrics/interfaces.go

@@ -0,0 +1,73 @@
+package metrics
+
+import (
+	"net/http"
+	"time"
+
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
+)
+
+// Provider defines the interface for metric collection
+type Provider interface {
+	// RecordHTTPRequest records metrics for an HTTP request
+	RecordHTTPRequest(method, path, status string, duration time.Duration)
+
+	// IncRequestsInFlight increments the in-flight requests counter
+	IncRequestsInFlight()
+
+	// DecRequestsInFlight decrements the in-flight requests counter
+	DecRequestsInFlight()
+
+	// RecordDBQuery records metrics for a database query
+	RecordDBQuery(operation, table string, duration time.Duration, err error)
+
+	// RecordCacheHit records a cache hit
+	RecordCacheHit(provider string)
+
+	// RecordCacheMiss records a cache miss
+	RecordCacheMiss(provider string)
+
+	// UpdateCacheSize updates the cache size metric
+	UpdateCacheSize(provider string, size int64)
+
+	// Handler returns an HTTP handler for exposing metrics (e.g., /metrics endpoint)
+	Handler() http.Handler
+}
+
+// globalProvider is the global metrics provider
+var globalProvider Provider
+
+// SetProvider sets the global metrics provider
+func SetProvider(p Provider) {
+	globalProvider = p
+}
+
+// GetProvider returns the current metrics provider
+func GetProvider() Provider {
+	if globalProvider == nil {
+		// Return no-op provider if none is set
+		return &NoOpProvider{}
+	}
+	return globalProvider
+}
+
+// NoOpProvider is a no-op implementation of Provider
+type NoOpProvider struct{}
+
+func (n *NoOpProvider) RecordHTTPRequest(method, path, status string, duration time.Duration) {}
+func (n *NoOpProvider) IncRequestsInFlight()                                                  {}
+func (n *NoOpProvider) DecRequestsInFlight()                                                  {}
+func (n *NoOpProvider) RecordDBQuery(operation, table string, duration time.Duration, err error) {
+}
+func (n *NoOpProvider) RecordCacheHit(provider string)              {}
+func (n *NoOpProvider) RecordCacheMiss(provider string)             {}
+func (n *NoOpProvider) UpdateCacheSize(provider string, size int64) {}
+func (n *NoOpProvider) Handler() http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusNotFound)
+		_, err := w.Write([]byte("Metrics provider not configured"))
+		if err != nil {
+			logger.Warn("Failed to write. %v", err)
+		}
+	})
+}

pkg/metrics/prometheus.go

@@ -0,0 +1,174 @@
+package metrics
+
+import (
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+// PrometheusProvider implements the Provider interface using Prometheus
+type PrometheusProvider struct {
+	requestDuration  *prometheus.HistogramVec
+	requestTotal     *prometheus.CounterVec
+	requestsInFlight prometheus.Gauge
+	dbQueryDuration  *prometheus.HistogramVec
+	dbQueryTotal     *prometheus.CounterVec
+	cacheHits        *prometheus.CounterVec
+	cacheMisses      *prometheus.CounterVec
+	cacheSize        *prometheus.GaugeVec
+}
+
+// NewPrometheusProvider creates a new Prometheus metrics provider
+func NewPrometheusProvider() *PrometheusProvider {
+	return &PrometheusProvider{
+		requestDuration: promauto.NewHistogramVec(
+			prometheus.HistogramOpts{
+				Name:    "http_request_duration_seconds",
+				Help:    "HTTP request duration in seconds",
+				Buckets: prometheus.DefBuckets,
+			},
+			[]string{"method", "path", "status"},
+		),
+		requestTotal: promauto.NewCounterVec(
+			prometheus.CounterOpts{
+				Name: "http_requests_total",
+				Help: "Total number of HTTP requests",
+			},
+			[]string{"method", "path", "status"},
+		),
+
+		requestsInFlight: promauto.NewGauge(
+			prometheus.GaugeOpts{
+				Name: "http_requests_in_flight",
+				Help: "Current number of HTTP requests being processed",
+			},
+		),
+		dbQueryDuration: promauto.NewHistogramVec(
+			prometheus.HistogramOpts{
+				Name:    "db_query_duration_seconds",
+				Help:    "Database query duration in seconds",
+				Buckets: prometheus.DefBuckets,
+			},
+			[]string{"operation", "table"},
+		),
+		dbQueryTotal: promauto.NewCounterVec(
+			prometheus.CounterOpts{
+				Name: "db_queries_total",
+				Help: "Total number of database queries",
+			},
+			[]string{"operation", "table", "status"},
+		),
+		cacheHits: promauto.NewCounterVec(
+			prometheus.CounterOpts{
+				Name: "cache_hits_total",
+				Help: "Total number of cache hits",
+			},
+			[]string{"provider"},
+		),
+		cacheMisses: promauto.NewCounterVec(
+			prometheus.CounterOpts{
+				Name: "cache_misses_total",
+				Help: "Total number of cache misses",
+			},
+			[]string{"provider"},
+		),
+		cacheSize: promauto.NewGaugeVec(
+			prometheus.GaugeOpts{
+				Name: "cache_size_items",
+				Help: "Number of items in cache",
+			},
+			[]string{"provider"},
+		),
+	}
+}
+
+// ResponseWriter wraps http.ResponseWriter to capture status code
+type ResponseWriter struct {
+	http.ResponseWriter
+	statusCode int
+}
+
+func NewResponseWriter(w http.ResponseWriter) *ResponseWriter {
+	return &ResponseWriter{
+		ResponseWriter: w,
+		statusCode:     http.StatusOK,
+	}
+}
+
+func (rw *ResponseWriter) WriteHeader(code int) {
+	rw.statusCode = code
+	rw.ResponseWriter.WriteHeader(code)
+}
+
+// RecordHTTPRequest implements Provider interface
+func (p *PrometheusProvider) RecordHTTPRequest(method, path, status string, duration time.Duration) {
+	p.requestDuration.WithLabelValues(method, path, status).Observe(duration.Seconds())
+	p.requestTotal.WithLabelValues(method, path, status).Inc()
+}
+
+// IncRequestsInFlight implements Provider interface
+func (p *PrometheusProvider) IncRequestsInFlight() {
+	p.requestsInFlight.Inc()
+}
+
+// DecRequestsInFlight implements Provider interface
+func (p *PrometheusProvider) DecRequestsInFlight() {
+	p.requestsInFlight.Dec()
+}
+
+// RecordDBQuery implements Provider interface
+func (p *PrometheusProvider) RecordDBQuery(operation, table string, duration time.Duration, err error) {
+	status := "success"
+	if err != nil {
+		status = "error"
+	}
+	p.dbQueryDuration.WithLabelValues(operation, table).Observe(duration.Seconds())
+	p.dbQueryTotal.WithLabelValues(operation, table, status).Inc()
+}
+
+// RecordCacheHit implements Provider interface
+func (p *PrometheusProvider) RecordCacheHit(provider string) {
+	p.cacheHits.WithLabelValues(provider).Inc()
+}
+
+// RecordCacheMiss implements Provider interface
+func (p *PrometheusProvider) RecordCacheMiss(provider string) {
+	p.cacheMisses.WithLabelValues(provider).Inc()
+}
+
+// UpdateCacheSize implements Provider interface
+func (p *PrometheusProvider) UpdateCacheSize(provider string, size int64) {
+	p.cacheSize.WithLabelValues(provider).Set(float64(size))
+}
+
+// Handler implements Provider interface
+func (p *PrometheusProvider) Handler() http.Handler {
+	return promhttp.Handler()
+}
+
+// Middleware returns an HTTP middleware that collects metrics
+func (p *PrometheusProvider) Middleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		start := time.Now()
+
+		// Increment in-flight requests
+		p.IncRequestsInFlight()
+		defer p.DecRequestsInFlight()
+
+		// Wrap response writer to capture status code
+		rw := NewResponseWriter(w)
+
+		// Call next handler
+		next.ServeHTTP(rw, r)
+
+		// Record metrics
+		duration := time.Since(start)
+		status := strconv.Itoa(rw.statusCode)
+
+		p.RecordHTTPRequest(r.Method, r.URL.Path, status, duration)
+	})
+}

pkg/middleware/README.md

@@ -0,0 +1,806 @@
+# Middleware Package
+
+HTTP middleware utilities for security and performance.
+
+## Table of Contents
+
+1. [Rate Limiting](#rate-limiting)
+2. [Request Size Limits](#request-size-limits)
+3. [Input Sanitization](#input-sanitization)
+
+---
+
+## Rate Limiting
+
+Production-grade rate limiting using token bucket algorithm.
+
+### Quick Start
+
+```go
+import "github.com/bitechdev/ResolveSpec/pkg/middleware"
+
+// Create rate limiter: 100 requests per second, burst of 20
+rateLimiter := middleware.NewRateLimiter(100, 20)
+
+// Apply to all routes
+router.Use(rateLimiter.Middleware)
+```
+
+### Basic Usage
+
+```go
+package main
+
+import (
+    "log"
+    "net/http"
+
+    "github.com/bitechdev/ResolveSpec/pkg/middleware"
+    "github.com/gorilla/mux"
+)
+
+func main() {
+    router := mux.NewRouter()
+
+    // Rate limit: 10 requests per second, burst of 5
+    rateLimiter := middleware.NewRateLimiter(10, 5)
+    router.Use(rateLimiter.Middleware)
+
+    router.HandleFunc("/api/data", dataHandler)
+
+    log.Fatal(http.ListenAndServe(":8080", router))
+}
+```
+
+### Custom Key Extraction
+
+By default, rate limiting is per IP address. Customize the key:
+
+```go
+// Rate limit by User ID from header
+keyFunc := func(r *http.Request) string {
+    userID := r.Header.Get("X-User-ID")
+    if userID == "" {
+        return r.RemoteAddr // Fallback to IP
+    }
+    return "user:" + userID
+}
+
+router.Use(rateLimiter.MiddlewareWithKeyFunc(keyFunc))
+```
+
+### Advanced Key Functions
+
+**By API Key:**
+
+```go
+keyFunc := func(r *http.Request) string {
+    apiKey := r.Header.Get("X-API-Key")
+    if apiKey == "" {
+        return r.RemoteAddr
+    }
+    return "api:" + apiKey
+}
+```
+
+**By Authenticated User:**
+
+```go
+keyFunc := func(r *http.Request) string {
+    // Extract from JWT or session
+    user := getUserFromContext(r.Context())
+    if user != nil {
+        return "user:" + user.ID
+    }
+    return r.RemoteAddr
+}
+```
+
+**By Path + User:**
+
+```go
+keyFunc := func(r *http.Request) string {
+    user := getUserFromContext(r.Context())
+    if user != nil {
+        return fmt.Sprintf("user:%s:path:%s", user.ID, r.URL.Path)
+    }
+    return r.URL.Path + ":" + r.RemoteAddr
+}
+```
+
+### Different Limits Per Route
+
+```go
+func main() {
+    router := mux.NewRouter()
+
+    // Public endpoints: 10 rps
+    publicLimiter := middleware.NewRateLimiter(10, 5)
+
+    // API endpoints: 100 rps
+    apiLimiter := middleware.NewRateLimiter(100, 20)
+
+    // Admin endpoints: 1000 rps
+    adminLimiter := middleware.NewRateLimiter(1000, 50)
+
+    // Apply different limiters to subrouters
+    publicRouter := router.PathPrefix("/public").Subrouter()
+    publicRouter.Use(publicLimiter.Middleware)
+
+    apiRouter := router.PathPrefix("/api").Subrouter()
+    apiRouter.Use(apiLimiter.Middleware)
+
+    adminRouter := router.PathPrefix("/admin").Subrouter()
+    adminRouter.Use(adminLimiter.Middleware)
+}
+```
+
+### Rate Limit Response
+
+When rate limited, clients receive:
+
+```http
+HTTP/1.1 429 Too Many Requests
+Content-Type: text/plain
+
+```
+
+### Configuration Examples
+
+**Tight Rate Limit (Anti-abuse):**
+
+```go
+// 1 request per second, burst of 3
+rateLimiter := middleware.NewRateLimiter(1, 3)
+```
+
+**Moderate Rate Limit (Standard API):**
+
+```go
+// 100 requests per second, burst of 20
+rateLimiter := middleware.NewRateLimiter(100, 20)
+```
+
+**Generous Rate Limit (Internal Services):**
+
+```go
+// 1000 requests per second, burst of 100
+rateLimiter := middleware.NewRateLimiter(1000, 100)
+```
+
+**Time-based Limits:**
+
+```go
+// 60 requests per minute = 1 request per second
+rateLimiter := middleware.NewRateLimiter(1, 10)
+
+// 1000 requests per hour ≈ 0.28 requests per second
+rateLimiter := middleware.NewRateLimiter(0.28, 50)
+```
+
+### Understanding Burst
+
+The burst parameter allows short bursts above the rate:
+
+```go
+// Rate: 10 rps, Burst: 5
+// Allows up to 5 requests immediately, then 10/second
+rateLimiter := middleware.NewRateLimiter(10, 5)
+```
+
+**Bucket fills at rate:** 10 tokens/second
+**Bucket capacity:** 5 tokens
+**Request consumes:** 1 token
+
+**Example traffic pattern:**
+- T=0s: 5 requests → ✅ All allowed (burst)
+- T=0.1s: 1 request → ❌ Denied (bucket empty)
+- T=0.5s: 1 request → ✅ Allowed (bucket refilled 0.5 tokens)
+- T=1s: 1 request → ✅ Allowed (bucket has ~1 token)
+
+### Cleanup Behavior
+
+The rate limiter automatically cleans up inactive limiters every 5 minutes to prevent memory leaks.
+
+### Performance Characteristics
+
+- **Memory**: ~100 bytes per active limiter
+- **Throughput**: >1M requests/second
+- **Latency**: <1μs per request
+- **Concurrency**: Lock-free for rate checks
+
+### Production Deployment
+
+**With Reverse Proxy:**
+
+```go
+// Use X-Forwarded-For or X-Real-IP
+keyFunc := func(r *http.Request) string {
+    // Check proxy headers first
+    if ip := r.Header.Get("X-Forwarded-For"); ip != "" {
+        return strings.Split(ip, ",")[0]
+    }
+    if ip := r.Header.Get("X-Real-IP"); ip != "" {
+        return ip
+    }
+    return r.RemoteAddr
+}
+
+router.Use(rateLimiter.MiddlewareWithKeyFunc(keyFunc))
+```
+
+**Environment-based Configuration:**
+
+```go
+import "os"
+
+func getRateLimiter() *middleware.RateLimiter {
+    rps := getEnvFloat("RATE_LIMIT_RPS", 100)
+    burst := getEnvInt("RATE_LIMIT_BURST", 20)
+    return middleware.NewRateLimiter(rps, burst)
+}
+```
+
+### Testing Rate Limits
+
+```bash
+# Send 10 requests rapidly
+for i in {1..10}; do
+  curl -w "Status: %{http_code}\n" http://localhost:8080/api/data
+done
+```
+
+**Expected output:**
+```
+Status: 200  # Request 1-5 (within burst)
+Status: 200
+Status: 200
+Status: 200
+Status: 200
+Status: 429  # Request 6-10 (rate limited)
+Status: 429
+Status: 429
+Status: 429
+Status: 429
+```
+
+### Complete Example
+
+```go
+package main
+
+import (
+    "encoding/json"
+    "log"
+    "net/http"
+    "os"
+    "strconv"
+
+    "github.com/bitechdev/ResolveSpec/pkg/middleware"
+    "github.com/gorilla/mux"
+)
+
+func main() {
+    // Configuration from environment
+    rps, _ := strconv.ParseFloat(os.Getenv("RATE_LIMIT_RPS"), 64)
+    if rps == 0 {
+        rps = 100 // Default
+    }
+
+    burst, _ := strconv.Atoi(os.Getenv("RATE_LIMIT_BURST"))
+    if burst == 0 {
+        burst = 20 // Default
+    }
+
+    // Create rate limiter
+    rateLimiter := middleware.NewRateLimiter(rps, burst)
+
+    // Custom key extraction
+    keyFunc := func(r *http.Request) string {
+        // Try API key first
+        if apiKey := r.Header.Get("X-API-Key"); apiKey != "" {
+            return "api:" + apiKey
+        }
+        // Try authenticated user
+        if userID := r.Header.Get("X-User-ID"); userID != "" {
+            return "user:" + userID
+        }
+        // Fall back to IP
+        if ip := r.Header.Get("X-Forwarded-For"); ip != "" {
+            return ip
+        }
+        return r.RemoteAddr
+    }
+
+    // Create router
+    router := mux.NewRouter()
+
+    // Apply rate limiting
+    router.Use(rateLimiter.MiddlewareWithKeyFunc(keyFunc))
+
+    // Routes
+    router.HandleFunc("/api/data", dataHandler)
+    router.HandleFunc("/health", healthHandler)
+
+    log.Printf("Starting server with rate limit: %.1f rps, burst: %d", rps, burst)
+    log.Fatal(http.ListenAndServe(":8080", router))
+}
+
+func dataHandler(w http.ResponseWriter, r *http.Request) {
+    json.NewEncoder(w).Encode(map[string]string{
+        "message": "Data endpoint",
+    })
+}
+
+func healthHandler(w http.ResponseWriter, r *http.Request) {
+    w.WriteHeader(http.StatusOK)
+    w.Write([]byte("OK"))
+}
+```
+
+## Best Practices
+
+1. **Set Appropriate Limits**: Consider your backend capacity
+   - Database: Can it handle X queries/second?
+   - External APIs: What are their rate limits?
+   - Server resources: CPU, memory, connections
+
+2. **Use Burst Wisely**: Allow legitimate traffic spikes
+   - Too low: Reject valid bursts
+   - Too high: Allow abuse
+
+3. **Monitor Rate Limits**: Track how often limits are hit
+   ```go
+   // Log rate limit events
+   if rateLimited {
+       log.Printf("Rate limited: %s", clientKey)
+   }
+   ```
+
+4. **Provide Feedback**: Include rate limit headers (future enhancement)
+   ```http
+   X-RateLimit-Limit: 100
+   X-RateLimit-Remaining: 95
+   X-RateLimit-Reset: 1640000000
+   ```
+
+5. **Tiered Limits**: Different limits for different user tiers
+   ```go
+   func getRateLimiter(userTier string) *middleware.RateLimiter {
+       switch userTier {
+       case "premium":
+           return middleware.NewRateLimiter(1000, 100)
+       case "standard":
+           return middleware.NewRateLimiter(100, 20)
+       default:
+           return middleware.NewRateLimiter(10, 5)
+       }
+   }
+   ```
+
+---
+
+## Request Size Limits
+
+Protect against oversized request bodies with configurable size limits.
+
+### Quick Start
+
+```go
+import "github.com/bitechdev/ResolveSpec/pkg/middleware"
+
+// Default: 10MB limit
+sizeLimiter := middleware.NewRequestSizeLimiter(0)
+router.Use(sizeLimiter.Middleware)
+```
+
+### Custom Size Limit
+
+```go
+// 5MB limit
+sizeLimiter := middleware.NewRequestSizeLimiter(5 * 1024 * 1024)
+router.Use(sizeLimiter.Middleware)
+
+// Or use constants
+sizeLimiter := middleware.NewRequestSizeLimiter(middleware.Size5MB)
+```
+
+### Available Size Constants
+
+```go
+middleware.Size1MB    // 1 MB
+middleware.Size5MB    // 5 MB
+middleware.Size10MB   // 10 MB (default)
+middleware.Size50MB   // 50 MB
+middleware.Size100MB  // 100 MB
+```
+
+### Different Limits Per Route
+
+```go
+func main() {
+    router := mux.NewRouter()
+
+    // File upload endpoint: 50MB
+    uploadLimiter := middleware.NewRequestSizeLimiter(middleware.Size50MB)
+    uploadRouter := router.PathPrefix("/upload").Subrouter()
+    uploadRouter.Use(uploadLimiter.Middleware)
+
+    // API endpoints: 1MB
+    apiLimiter := middleware.NewRequestSizeLimiter(middleware.Size1MB)
+    apiRouter := router.PathPrefix("/api").Subrouter()
+    apiRouter.Use(apiLimiter.Middleware)
+}
+```
+
+### Dynamic Size Limits
+
+```go
+// Custom size based on request
+sizeFunc := func(r *http.Request) int64 {
+    // Premium users get 50MB
+    if isPremiumUser(r) {
+        return middleware.Size50MB
+    }
+    // Free users get 5MB
+    return middleware.Size5MB
+}
+
+router.Use(sizeLimiter.MiddlewareWithCustomSize(sizeFunc))
+```
+
+**By Content-Type:**
+
+```go
+sizeFunc := func(r *http.Request) int64 {
+    contentType := r.Header.Get("Content-Type")
+
+    switch {
+    case strings.Contains(contentType, "multipart/form-data"):
+        return middleware.Size50MB // File uploads
+    case strings.Contains(contentType, "application/json"):
+        return middleware.Size1MB // JSON APIs
+    default:
+        return middleware.Size10MB // Default
+    }
+}
+```
+
+### Error Response
+
+When size limit exceeded:
+
+```http
+HTTP/1.1 413 Request Entity Too Large
+X-Max-Request-Size: 10485760
+
+http: request body too large
+```
+
+### Complete Example
+
+```go
+package main
+
+import (
+    "log"
+    "net/http"
+
+    "github.com/bitechdev/ResolveSpec/pkg/middleware"
+    "github.com/gorilla/mux"
+)
+
+func main() {
+    router := mux.NewRouter()
+
+    // API routes: 1MB limit
+    api := router.PathPrefix("/api").Subrouter()
+    apiLimiter := middleware.NewRequestSizeLimiter(middleware.Size1MB)
+    api.Use(apiLimiter.Middleware)
+    api.HandleFunc("/users", createUserHandler).Methods("POST")
+
+    // Upload routes: 50MB limit
+    upload := router.PathPrefix("/upload").Subrouter()
+    uploadLimiter := middleware.NewRequestSizeLimiter(middleware.Size50MB)
+    upload.Use(uploadLimiter.Middleware)
+    upload.HandleFunc("/file", uploadFileHandler).Methods("POST")
+
+    log.Fatal(http.ListenAndServe(":8080", router))
+}
+```
+
+---
+
+## Input Sanitization
+
+Protect against XSS, injection attacks, and malicious input.
+
+### Quick Start
+
+```go
+import "github.com/bitechdev/ResolveSpec/pkg/middleware"
+
+// Default sanitizer (safe defaults)
+sanitizer := middleware.DefaultSanitizer()
+router.Use(sanitizer.Middleware)
+```
+
+### Sanitizer Types
+
+**Default Sanitizer (Recommended):**
+
+```go
+sanitizer := middleware.DefaultSanitizer()
+// ✓ Escapes HTML entities
+// ✓ Removes null bytes
+// ✓ Removes control characters
+// ✓ Blocks XSS patterns (script tags, event handlers)
+// ✗ Does not strip HTML (allows legitimate content)
+```
+
+**Strict Sanitizer:**
+
+```go
+sanitizer := middleware.StrictSanitizer()
+// ✓ All default features
+// ✓ Strips ALL HTML tags
+// ✓ Max string length: 10,000 chars
+```
+
+### Custom Configuration
+
+```go
+sanitizer := &middleware.Sanitizer{
+    StripHTML:          true,  // Remove HTML tags
+    EscapeHTML:         false, // Don't escape (already stripped)
+    RemoveNullBytes:    true,  // Remove \x00
+    RemoveControlChars: true,  // Remove dangerous control chars
+    MaxStringLength:    5000,  // Limit to 5000 chars
+
+    // Block patterns (regex)
+    BlockPatterns: []*regexp.Regexp{
+        regexp.MustCompile(`(?i)<script`),
+        regexp.MustCompile(`(?i)javascript:`),
+    },
+
+    // Custom sanitization function
+    CustomSanitizer: func(s string) string {
+        // Your custom logic
+        return strings.ToLower(s)
+    },
+}
+
+router.Use(sanitizer.Middleware)
+```
+
+### What Gets Sanitized
+
+**Automatic (via middleware):**
+- Query parameters
+- Headers (User-Agent, Referer, X-Forwarded-For, X-Real-IP)
+
+**Manual (in your handler):**
+- Request body (JSON, form data)
+- Database queries
+- File names
+
+### Manual Sanitization
+
+**String Values:**
+
+```go
+sanitizer := middleware.DefaultSanitizer()
+
+// Sanitize user input
+username := sanitizer.Sanitize(r.FormValue("username"))
+email := sanitizer.Sanitize(r.FormValue("email"))
+```
+
+**Map/JSON Data:**
+
+```go
+var data map[string]interface{}
+json.Unmarshal(body, &data)
+
+// Sanitize all string values recursively
+sanitizedData := sanitizer.SanitizeMap(data)
+```
+
+**Nested Structures:**
+
+```go
+type User struct {
+    Name    string
+    Email   string
+    Bio     string
+    Profile map[string]interface{}
+}
+
+// After unmarshaling
+user.Name = sanitizer.Sanitize(user.Name)
+user.Email = sanitizer.Sanitize(user.Email)
+user.Bio = sanitizer.Sanitize(user.Bio)
+user.Profile = sanitizer.SanitizeMap(user.Profile)
+```
+
+### Specialized Sanitizers
+
+**Filenames:**
+
+```go
+import "github.com/bitechdev/ResolveSpec/pkg/middleware"
+
+filename := middleware.SanitizeFilename(uploadedFilename)
+// Removes: .., /, \, null bytes
+// Limits: 255 characters
+```
+
+**Emails:**
+
+```go
+email := middleware.SanitizeEmail(" USER@EXAMPLE.COM ")
+// Result: "user@example.com"
+// Trims, lowercases, removes null bytes
+```
+
+**URLs:**
+
+```go
+url := middleware.SanitizeURL(userInput)
+// Blocks: javascript:, data: protocols
+// Removes: null bytes
+```
+
+### Blocked Patterns (Default)
+
+The default sanitizer blocks:
+
+1. **Script tags**: `<script>...</script>`
+2. **JavaScript protocol**: `javascript:alert(1)`
+3. **Event handlers**: `onclick="..."`, `onerror="..."`
+4. **Iframes**: `<iframe src="...">`
+5. **Objects**: `<object data="...">`
+6. **Embeds**: `<embed src="...">`
+
+### Security Best Practices
+
+**1. Layer Defense:**
+
+```go
+// Layer 1: Middleware (query params, headers)
+router.Use(sanitizer.Middleware)
+
+// Layer 2: Input validation (in handler)
+func createUserHandler(w http.ResponseWriter, r *http.Request) {
+    var user User
+    json.NewDecoder(r.Body).Decode(&user)
+
+    // Sanitize
+    user.Name = sanitizer.Sanitize(user.Name)
+    user.Email = middleware.SanitizeEmail(user.Email)
+
+    // Validate
+    if !isValidEmail(user.Email) {
+        http.Error(w, "Invalid email", 400)
+        return
+    }
+
+    // Use parameterized queries (prevents SQL injection)
+    db.Exec("INSERT INTO users (name, email) VALUES (?, ?)",
+        user.Name, user.Email)
+}
+```
+
+**2. Context-Aware Sanitization:**
+
+```go
+// HTML content (user posts, comments)
+sanitizer := middleware.StrictSanitizer()
+post.Content = sanitizer.Sanitize(post.Content)
+
+// Structured data (JSON API)
+sanitizer := middleware.DefaultSanitizer()
+data = sanitizer.SanitizeMap(jsonData)
+
+// Search queries (preserve special chars)
+query = middleware.SanitizeFilename(searchTerm) // Light sanitization
+```
+
+**3. Output Encoding:**
+
+```go
+// When rendering HTML
+import "html/template"
+
+tmpl := template.Must(template.New("page").Parse(`
+    <h1>{{.Title}}</h1>
+    <p>{{.Content}}</p>
+`))
+
+// template.HTML automatically escapes
+tmpl.Execute(w, data)
+```
+
+### Complete Example
+
+```go
+package main
+
+import (
+    "encoding/json"
+    "log"
+    "net/http"
+
+    "github.com/bitechdev/ResolveSpec/pkg/middleware"
+    "github.com/gorilla/mux"
+)
+
+func main() {
+    router := mux.NewRouter()
+
+    // Apply sanitization middleware
+    sanitizer := middleware.DefaultSanitizer()
+    router.Use(sanitizer.Middleware)
+
+    router.HandleFunc("/api/users", createUserHandler).Methods("POST")
+
+    log.Fatal(http.ListenAndServe(":8080", router))
+}
+
+func createUserHandler(w http.ResponseWriter, r *http.Request) {
+    sanitizer := middleware.DefaultSanitizer()
+
+    var user struct {
+        Name  string `json:"name"`
+        Email string `json:"email"`
+        Bio   string `json:"bio"`
+    }
+
+    if err := json.NewDecoder(r.Body).Decode(&user); err != nil {
+        http.Error(w, "Invalid JSON", 400)
+        return
+    }
+
+    // Sanitize inputs
+    user.Name = sanitizer.Sanitize(user.Name)
+    user.Email = middleware.SanitizeEmail(user.Email)
+    user.Bio = sanitizer.Sanitize(user.Bio)
+
+    // Validate
+    if len(user.Name) == 0 || len(user.Email) == 0 {
+        http.Error(w, "Name and email required", 400)
+        return
+    }
+
+    // Save to database (use parameterized queries!)
+    // db.Exec("INSERT INTO users (name, email, bio) VALUES (?, ?, ?)",
+    //     user.Name, user.Email, user.Bio)
+
+    w.WriteHeader(http.StatusCreated)
+    json.NewEncoder(w).Encode(map[string]string{
+        "status": "created",
+    })
+}
+```
+
+### Testing Sanitization
+
+```bash
+# Test XSS prevention
+curl -X POST http://localhost:8080/api/users \
+  -H "Content-Type: application/json" \
+  -d '{
+    "name": "<script>alert(1)</script>John",
+    "email": "test@example.com",
+    "bio": "My bio with <iframe src=\"evil.com\"></iframe>"
+  }'
+
+# Script tags and iframes should be removed
+```
+
+### Performance
+
+- **Overhead**: <1ms per request for typical payloads
+- **Regex compilation**: Done once at initialization
+- **Safe for production**: Minimal performance impact
+- **Safe for production**: Minimal performance impact

pkg/middleware/blacklist.go

@@ -0,0 +1,212 @@
+package middleware
+
+import (
+	"encoding/json"
+	"net"
+	"net/http"
+	"strings"
+	"sync"
+
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
+)
+
+// IPBlacklist provides IP blocking functionality
+type IPBlacklist struct {
+	mu       sync.RWMutex
+	ips      map[string]bool // Individual IPs
+	cidrs    []*net.IPNet    // CIDR ranges
+	reason   map[string]string
+	useProxy bool // Whether to check X-Forwarded-For headers
+}
+
+// BlacklistConfig configures the IP blacklist
+type BlacklistConfig struct {
+	// UseProxy indicates whether to extract IP from X-Forwarded-For/X-Real-IP headers
+	UseProxy bool
+}
+
+// NewIPBlacklist creates a new IP blacklist
+func NewIPBlacklist(config BlacklistConfig) *IPBlacklist {
+	return &IPBlacklist{
+		ips:      make(map[string]bool),
+		cidrs:    make([]*net.IPNet, 0),
+		reason:   make(map[string]string),
+		useProxy: config.UseProxy,
+	}
+}
+
+// BlockIP blocks a single IP address
+func (bl *IPBlacklist) BlockIP(ip string, reason string) error {
+	// Validate IP
+	if net.ParseIP(ip) == nil {
+		return &net.ParseError{Type: "IP address", Text: ip}
+	}
+
+	bl.mu.Lock()
+	defer bl.mu.Unlock()
+
+	bl.ips[ip] = true
+	if reason != "" {
+		bl.reason[ip] = reason
+	}
+	return nil
+}
+
+// BlockCIDR blocks an IP range using CIDR notation
+func (bl *IPBlacklist) BlockCIDR(cidr string, reason string) error {
+	_, ipNet, err := net.ParseCIDR(cidr)
+	if err != nil {
+		return err
+	}
+
+	bl.mu.Lock()
+	defer bl.mu.Unlock()
+
+	bl.cidrs = append(bl.cidrs, ipNet)
+	if reason != "" {
+		bl.reason[cidr] = reason
+	}
+	return nil
+}
+
+// UnblockIP removes an IP from the blacklist
+func (bl *IPBlacklist) UnblockIP(ip string) {
+	bl.mu.Lock()
+	defer bl.mu.Unlock()
+
+	delete(bl.ips, ip)
+	delete(bl.reason, ip)
+}
+
+// UnblockCIDR removes a CIDR range from the blacklist
+func (bl *IPBlacklist) UnblockCIDR(cidr string) {
+	bl.mu.Lock()
+	defer bl.mu.Unlock()
+
+	// Find and remove the CIDR
+	for i, ipNet := range bl.cidrs {
+		if ipNet.String() == cidr {
+			bl.cidrs = append(bl.cidrs[:i], bl.cidrs[i+1:]...)
+			break
+		}
+	}
+	delete(bl.reason, cidr)
+}
+
+// IsBlocked checks if an IP is blacklisted
+func (bl *IPBlacklist) IsBlocked(ip string) (blacklist bool, reason string) {
+	bl.mu.RLock()
+	defer bl.mu.RUnlock()
+
+	// Check individual IPs
+	if bl.ips[ip] {
+		return true, bl.reason[ip]
+	}
+
+	// Check CIDR ranges
+	parsedIP := net.ParseIP(ip)
+	if parsedIP == nil {
+		return false, ""
+	}
+
+	for i, ipNet := range bl.cidrs {
+		if ipNet.Contains(parsedIP) {
+			cidr := ipNet.String()
+			// Try to find reason by CIDR or by index
+			if reason, ok := bl.reason[cidr]; ok {
+				return true, reason
+			}
+			// Check if reason was stored by original CIDR string
+			for key, reason := range bl.reason {
+				if strings.Contains(key, "/") && key == cidr {
+					return true, reason
+				}
+			}
+			// Return true even if no reason found
+			if i < len(bl.cidrs) {
+				return true, ""
+			}
+		}
+	}
+
+	return false, ""
+}
+
+// GetBlacklist returns all blacklisted IPs and CIDRs
+func (bl *IPBlacklist) GetBlacklist() (ips []string, cidrs []string) {
+	bl.mu.RLock()
+	defer bl.mu.RUnlock()
+
+	ips = make([]string, 0, len(bl.ips))
+	for ip := range bl.ips {
+		ips = append(ips, ip)
+	}
+
+	cidrs = make([]string, 0, len(bl.cidrs))
+	for _, ipNet := range bl.cidrs {
+		cidrs = append(cidrs, ipNet.String())
+	}
+
+	return ips, cidrs
+}
+
+// Middleware returns an HTTP middleware that blocks blacklisted IPs
+func (bl *IPBlacklist) Middleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var clientIP string
+		if bl.useProxy {
+			clientIP = getClientIP(r)
+			// Clean up IPv6 brackets if present
+			clientIP = strings.Trim(clientIP, "[]")
+		} else {
+			// Extract IP from RemoteAddr
+			if idx := strings.LastIndex(r.RemoteAddr, ":"); idx != -1 {
+				clientIP = r.RemoteAddr[:idx]
+			} else {
+				clientIP = r.RemoteAddr
+			}
+			clientIP = strings.Trim(clientIP, "[]")
+		}
+
+		blocked, reason := bl.IsBlocked(clientIP)
+		if blocked {
+			response := map[string]interface{}{
+				"error":   "forbidden",
+				"message": "Access denied",
+			}
+			if reason != "" {
+				response["reason"] = reason
+			}
+
+			w.Header().Set("Content-Type", "application/json")
+			w.WriteHeader(http.StatusForbidden)
+			err := json.NewEncoder(w).Encode(response)
+			if err != nil {
+				logger.Debug("Failed to write blacklist response: %v", err)
+			}
+			return
+		}
+
+		next.ServeHTTP(w, r)
+	})
+}
+
+// StatsHandler returns an HTTP handler that shows blacklist statistics
+func (bl *IPBlacklist) StatsHandler() http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		ips, cidrs := bl.GetBlacklist()
+
+		stats := map[string]interface{}{
+			"blocked_ips":   ips,
+			"blocked_cidrs": cidrs,
+			"total_ips":     len(ips),
+			"total_cidrs":   len(cidrs),
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		err := json.NewEncoder(w).Encode(stats)
+		if err != nil {
+			logger.Debug("Failed to encode stats: %v", err)
+		}
+	})
+}

pkg/middleware/blacklist_test.go

@@ -0,0 +1,254 @@
+package middleware
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestIPBlacklist_BlockIP(t *testing.T) {
+	bl := NewIPBlacklist(BlacklistConfig{UseProxy: false})
+
+	// Block an IP
+	err := bl.BlockIP("192.168.1.100", "Suspicious activity")
+	if err != nil {
+		t.Fatalf("BlockIP() error = %v", err)
+	}
+
+	// Check if IP is blocked
+	blocked, reason := bl.IsBlocked("192.168.1.100")
+	if !blocked {
+		t.Error("IP should be blocked")
+	}
+	if reason != "Suspicious activity" {
+		t.Errorf("Reason = %q, want %q", reason, "Suspicious activity")
+	}
+
+	// Check non-blocked IP
+	blocked, _ = bl.IsBlocked("192.168.1.1")
+	if blocked {
+		t.Error("IP should not be blocked")
+	}
+}
+
+func TestIPBlacklist_BlockCIDR(t *testing.T) {
+	bl := NewIPBlacklist(BlacklistConfig{UseProxy: false})
+
+	// Block a CIDR range
+	err := bl.BlockCIDR("10.0.0.0/24", "Internal network blocked")
+	if err != nil {
+		t.Fatalf("BlockCIDR() error = %v", err)
+	}
+
+	// Check IPs in range
+	testIPs := []string{
+		"10.0.0.1",
+		"10.0.0.100",
+		"10.0.0.254",
+	}
+
+	for _, ip := range testIPs {
+		blocked, _ := bl.IsBlocked(ip)
+		if !blocked {
+			t.Errorf("IP %s should be blocked by CIDR", ip)
+		}
+	}
+
+	// Check IP outside range
+	blocked, _ := bl.IsBlocked("10.0.1.1")
+	if blocked {
+		t.Error("IP outside CIDR range should not be blocked")
+	}
+}
+
+func TestIPBlacklist_UnblockIP(t *testing.T) {
+	bl := NewIPBlacklist(BlacklistConfig{UseProxy: false})
+
+	// Block and then unblock
+	bl.BlockIP("192.168.1.100", "Test")
+
+	blocked, _ := bl.IsBlocked("192.168.1.100")
+	if !blocked {
+		t.Error("IP should be blocked")
+	}
+
+	bl.UnblockIP("192.168.1.100")
+
+	blocked, _ = bl.IsBlocked("192.168.1.100")
+	if blocked {
+		t.Error("IP should be unblocked")
+	}
+}
+
+func TestIPBlacklist_UnblockCIDR(t *testing.T) {
+	bl := NewIPBlacklist(BlacklistConfig{UseProxy: false})
+
+	// Block and then unblock CIDR
+	bl.BlockCIDR("10.0.0.0/24", "Test")
+
+	blocked, _ := bl.IsBlocked("10.0.0.1")
+	if !blocked {
+		t.Error("IP should be blocked by CIDR")
+	}
+
+	bl.UnblockCIDR("10.0.0.0/24")
+
+	blocked, _ = bl.IsBlocked("10.0.0.1")
+	if blocked {
+		t.Error("IP should be unblocked after CIDR removal")
+	}
+}
+
+func TestIPBlacklist_Middleware(t *testing.T) {
+	bl := NewIPBlacklist(BlacklistConfig{UseProxy: false})
+	bl.BlockIP("192.168.1.100", "Banned")
+
+	handler := bl.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte("OK"))
+	}))
+
+	// Blocked IP should get 403
+	t.Run("BlockedIP", func(t *testing.T) {
+		req := httptest.NewRequest("GET", "/test", nil)
+		req.RemoteAddr = "192.168.1.100:12345"
+		w := httptest.NewRecorder()
+
+		handler.ServeHTTP(w, req)
+
+		if w.Code != http.StatusForbidden {
+			t.Errorf("Status = %d, want %d", w.Code, http.StatusForbidden)
+		}
+
+		var response map[string]interface{}
+		if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+			t.Fatalf("Failed to parse response: %v", err)
+		}
+
+		if response["error"] != "forbidden" {
+			t.Errorf("Error = %v, want %q", response["error"], "forbidden")
+		}
+	})
+
+	// Allowed IP should succeed
+	t.Run("AllowedIP", func(t *testing.T) {
+		req := httptest.NewRequest("GET", "/test", nil)
+		req.RemoteAddr = "192.168.1.1:12345"
+		w := httptest.NewRecorder()
+
+		handler.ServeHTTP(w, req)
+
+		if w.Code != http.StatusOK {
+			t.Errorf("Status = %d, want %d", w.Code, http.StatusOK)
+		}
+	})
+}
+
+func TestIPBlacklist_MiddlewareWithProxy(t *testing.T) {
+	bl := NewIPBlacklist(BlacklistConfig{UseProxy: true})
+	bl.BlockIP("203.0.113.1", "Blocked via proxy")
+
+	handler := bl.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	// Test X-Forwarded-For
+	t.Run("X-Forwarded-For", func(t *testing.T) {
+		req := httptest.NewRequest("GET", "/test", nil)
+		req.RemoteAddr = "10.0.0.1:12345"
+		req.Header.Set("X-Forwarded-For", "203.0.113.1")
+		w := httptest.NewRecorder()
+
+		handler.ServeHTTP(w, req)
+
+		if w.Code != http.StatusForbidden {
+			t.Errorf("Status = %d, want %d", w.Code, http.StatusForbidden)
+		}
+	})
+
+	// Test X-Real-IP
+	t.Run("X-Real-IP", func(t *testing.T) {
+		req := httptest.NewRequest("GET", "/test", nil)
+		req.RemoteAddr = "10.0.0.1:12345"
+		req.Header.Set("X-Real-IP", "203.0.113.1")
+		w := httptest.NewRecorder()
+
+		handler.ServeHTTP(w, req)
+
+		if w.Code != http.StatusForbidden {
+			t.Errorf("Status = %d, want %d", w.Code, http.StatusForbidden)
+		}
+	})
+}
+
+func TestIPBlacklist_StatsHandler(t *testing.T) {
+	bl := NewIPBlacklist(BlacklistConfig{UseProxy: false})
+	bl.BlockIP("192.168.1.100", "Test1")
+	bl.BlockIP("192.168.1.101", "Test2")
+	bl.BlockCIDR("10.0.0.0/24", "Test CIDR")
+
+	handler := bl.StatsHandler()
+
+	req := httptest.NewRequest("GET", "/blacklist-stats", nil)
+	w := httptest.NewRecorder()
+
+	handler.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Status = %d, want %d", w.Code, http.StatusOK)
+	}
+
+	var stats map[string]interface{}
+	if err := json.Unmarshal(w.Body.Bytes(), &stats); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if int(stats["total_ips"].(float64)) != 2 {
+		t.Errorf("total_ips = %v, want 2", stats["total_ips"])
+	}
+
+	if int(stats["total_cidrs"].(float64)) != 1 {
+		t.Errorf("total_cidrs = %v, want 1", stats["total_cidrs"])
+	}
+}
+
+func TestIPBlacklist_GetBlacklist(t *testing.T) {
+	bl := NewIPBlacklist(BlacklistConfig{UseProxy: false})
+	bl.BlockIP("192.168.1.100", "")
+	bl.BlockIP("192.168.1.101", "")
+	bl.BlockCIDR("10.0.0.0/24", "")
+
+	ips, cidrs := bl.GetBlacklist()
+
+	if len(ips) != 2 {
+		t.Errorf("len(ips) = %d, want 2", len(ips))
+	}
+
+	if len(cidrs) != 1 {
+		t.Errorf("len(cidrs) = %d, want 1", len(cidrs))
+	}
+
+	// Verify CIDR format
+	if cidrs[0] != "10.0.0.0/24" {
+		t.Errorf("CIDR = %q, want %q", cidrs[0], "10.0.0.0/24")
+	}
+}
+
+func TestIPBlacklist_InvalidIP(t *testing.T) {
+	bl := NewIPBlacklist(BlacklistConfig{UseProxy: false})
+
+	err := bl.BlockIP("invalid-ip", "Test")
+	if err == nil {
+		t.Error("BlockIP() should return error for invalid IP")
+	}
+}
+
+func TestIPBlacklist_InvalidCIDR(t *testing.T) {
+	bl := NewIPBlacklist(BlacklistConfig{UseProxy: false})
+
+	err := bl.BlockCIDR("invalid-cidr", "Test")
+	if err == nil {
+		t.Error("BlockCIDR() should return error for invalid CIDR")
+	}
+}

pkg/middleware/ratelimit.go

@@ -0,0 +1,233 @@
+// Package middleware provides HTTP middleware functionalities such as rate limiting and IP blacklisting.
+package middleware
+
+//nolint:all
+import (
+	"encoding/json"
+	"net/http"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
+	"golang.org/x/time/rate"
+)
+
+// RateLimiter provides rate limiting functionality
+type RateLimiter struct {
+	mu       sync.RWMutex
+	limiters map[string]*rate.Limiter
+	rate     rate.Limit
+	burst    int
+	cleanup  time.Duration
+}
+
+// NewRateLimiter creates a new rate limiter
+// rps is requests per second, burst is the maximum burst size
+func NewRateLimiter(rps float64, burst int) *RateLimiter {
+	rl := &RateLimiter{
+		limiters: make(map[string]*rate.Limiter),
+		rate:     rate.Limit(rps),
+		burst:    burst,
+		cleanup:  5 * time.Minute, // Clean up stale limiters every 5 minutes
+	}
+
+	// Start cleanup goroutine
+	go rl.cleanupRoutine()
+
+	return rl
+}
+
+// getLimiter returns the rate limiter for a given key (e.g., IP address)
+func (rl *RateLimiter) getLimiter(key string) *rate.Limiter {
+	rl.mu.RLock()
+	limiter, exists := rl.limiters[key]
+	rl.mu.RUnlock()
+
+	if exists {
+		return limiter
+	}
+
+	rl.mu.Lock()
+	defer rl.mu.Unlock()
+
+	// Double-check after acquiring write lock
+	if limiter, exists := rl.limiters[key]; exists {
+		return limiter
+	}
+
+	limiter = rate.NewLimiter(rl.rate, rl.burst)
+	rl.limiters[key] = limiter
+	return limiter
+}
+
+// cleanupRoutine periodically removes inactive limiters
+func (rl *RateLimiter) cleanupRoutine() {
+	ticker := time.NewTicker(rl.cleanup)
+	defer ticker.Stop()
+
+	for range ticker.C {
+		rl.mu.Lock()
+		// Simple cleanup: remove all limiters
+		// In production, you might want to track last access time
+		rl.limiters = make(map[string]*rate.Limiter)
+		rl.mu.Unlock()
+	}
+}
+
+// Middleware returns an HTTP middleware that applies rate limiting
+// Automatically handles X-Forwarded-For headers when behind a proxy
+func (rl *RateLimiter) Middleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Extract client IP, handling proxy headers
+		key := getClientIP(r)
+
+		limiter := rl.getLimiter(key)
+
+		if !limiter.Allow() {
+			http.Error(w, `{"error":"rate_limit_exceeded","message":"Too many requests"}`, http.StatusTooManyRequests)
+			return
+		}
+
+		next.ServeHTTP(w, r)
+	})
+}
+
+// MiddlewareWithKeyFunc returns an HTTP middleware with a custom key extraction function
+func (rl *RateLimiter) MiddlewareWithKeyFunc(keyFunc func(*http.Request) string) func(http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			key := keyFunc(r)
+			if key == "" {
+				key = r.RemoteAddr
+			}
+
+			limiter := rl.getLimiter(key)
+
+			if !limiter.Allow() {
+				http.Error(w, `{"error":"rate_limit_exceeded","message":"Too many requests"}`, http.StatusTooManyRequests)
+				return
+			}
+
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
+// RateLimitInfo contains information about a specific IP's rate limit status
+type RateLimitInfo struct {
+	IP              string  `json:"ip"`
+	TokensRemaining float64 `json:"tokens_remaining"`
+	Limit           float64 `json:"limit"`
+	Burst           int     `json:"burst"`
+}
+
+// GetTrackedIPs returns all IPs currently being tracked by the rate limiter
+func (rl *RateLimiter) GetTrackedIPs() []string {
+	rl.mu.RLock()
+	defer rl.mu.RUnlock()
+
+	ips := make([]string, 0, len(rl.limiters))
+	for ip := range rl.limiters {
+		ips = append(ips, ip)
+	}
+	return ips
+}
+
+// GetRateLimitInfo returns rate limit information for a specific IP
+func (rl *RateLimiter) GetRateLimitInfo(ip string) *RateLimitInfo {
+	rl.mu.RLock()
+	limiter, exists := rl.limiters[ip]
+	rl.mu.RUnlock()
+
+	if !exists {
+		// Return default info for untracked IP
+		return &RateLimitInfo{
+			IP:              ip,
+			TokensRemaining: float64(rl.burst),
+			Limit:           float64(rl.rate),
+			Burst:           rl.burst,
+		}
+	}
+
+	return &RateLimitInfo{
+		IP:              ip,
+		TokensRemaining: limiter.Tokens(),
+		Limit:           float64(rl.rate),
+		Burst:           rl.burst,
+	}
+}
+
+// GetAllRateLimitInfo returns rate limit information for all tracked IPs
+func (rl *RateLimiter) GetAllRateLimitInfo() []*RateLimitInfo {
+	ips := rl.GetTrackedIPs()
+	info := make([]*RateLimitInfo, 0, len(ips))
+
+	for _, ip := range ips {
+		info = append(info, rl.GetRateLimitInfo(ip))
+	}
+
+	return info
+}
+
+// StatsHandler returns an HTTP handler that exposes rate limit statistics
+// Example: GET /rate-limit-stats
+func (rl *RateLimiter) StatsHandler() http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Support querying specific IP via ?ip=x.x.x.x
+		if ip := r.URL.Query().Get("ip"); ip != "" {
+			info := rl.GetRateLimitInfo(ip)
+			w.Header().Set("Content-Type", "application/json")
+			err := json.NewEncoder(w).Encode(info)
+			if err != nil {
+				logger.Debug("Failed to encode json: %v", err)
+			}
+			return
+		}
+
+		// Return all tracked IPs
+		allInfo := rl.GetAllRateLimitInfo()
+
+		stats := map[string]interface{}{
+			"total_tracked_ips": len(allInfo),
+			"rate_limit_config": map[string]interface{}{
+				"requests_per_second": float64(rl.rate),
+				"burst":               rl.burst,
+			},
+			"tracked_ips": allInfo,
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		err := json.NewEncoder(w).Encode(stats)
+		if err != nil {
+			logger.Debug("Failed to encode json: %v", err)
+		}
+	})
+}
+
+// getClientIP extracts the real client IP from the request
+// Handles X-Forwarded-For, X-Real-IP, and falls back to RemoteAddr
+func getClientIP(r *http.Request) string {
+	// Check X-Forwarded-For header (most common in production)
+	// Format: X-Forwarded-For: client, proxy1, proxy2
+	if xff := r.Header.Get("X-Forwarded-For"); xff != "" {
+		// Take the first IP (the original client)
+		if idx := strings.Index(xff, ","); idx != -1 {
+			return strings.TrimSpace(xff[:idx])
+		}
+		return strings.TrimSpace(xff)
+	}
+
+	// Check X-Real-IP header (used by some proxies like nginx)
+	if xri := r.Header.Get("X-Real-IP"); xri != "" {
+		return strings.TrimSpace(xri)
+	}
+
+	// Fall back to RemoteAddr
+	// Remove port if present (format: "ip:port")
+	if idx := strings.LastIndex(r.RemoteAddr, ":"); idx != -1 {
+		return r.RemoteAddr[:idx]
+	}
+
+	return r.RemoteAddr
+}

pkg/middleware/ratelimit_test.go

@@ -0,0 +1,388 @@
+package middleware
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+)
+
+func TestRateLimiter(t *testing.T) {
+	// Create rate limiter: 2 requests per second, burst of 2
+	rl := NewRateLimiter(2, 2)
+
+	handler := rl.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte("OK"))
+	}))
+
+	// First request should succeed
+	req := httptest.NewRequest("GET", "/test", nil)
+	req.RemoteAddr = "192.168.1.1:12345"
+	w := httptest.NewRecorder()
+	handler.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("First request failed: got %d, want %d", w.Code, http.StatusOK)
+	}
+
+	// Second request should succeed (within burst)
+	w = httptest.NewRecorder()
+	handler.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Second request failed: got %d, want %d", w.Code, http.StatusOK)
+	}
+
+	// Third request should be rate limited
+	w = httptest.NewRecorder()
+	handler.ServeHTTP(w, req)
+
+	if w.Code != http.StatusTooManyRequests {
+		t.Errorf("Third request should be rate limited: got %d, want %d", w.Code, http.StatusTooManyRequests)
+	}
+
+	// Wait for rate limiter to refill
+	time.Sleep(600 * time.Millisecond)
+
+	// Request should succeed again
+	w = httptest.NewRecorder()
+	handler.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Request after wait failed: got %d, want %d", w.Code, http.StatusOK)
+	}
+}
+
+func TestRateLimiterDifferentIPs(t *testing.T) {
+	rl := NewRateLimiter(1, 1)
+
+	handler := rl.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	// First IP
+	req1 := httptest.NewRequest("GET", "/test", nil)
+	req1.RemoteAddr = "192.168.1.1:12345"
+
+	// Second IP
+	req2 := httptest.NewRequest("GET", "/test", nil)
+	req2.RemoteAddr = "192.168.1.2:12345"
+
+	// Both should succeed (different IPs)
+	w1 := httptest.NewRecorder()
+	handler.ServeHTTP(w1, req1)
+
+	w2 := httptest.NewRecorder()
+	handler.ServeHTTP(w2, req2)
+
+	if w1.Code != http.StatusOK {
+		t.Errorf("First IP request failed: got %d, want %d", w1.Code, http.StatusOK)
+	}
+
+	if w2.Code != http.StatusOK {
+		t.Errorf("Second IP request failed: got %d, want %d", w2.Code, http.StatusOK)
+	}
+}
+
+func TestGetClientIP(t *testing.T) {
+	tests := []struct {
+		name          string
+		remoteAddr    string
+		xForwardedFor string
+		xRealIP       string
+		expectedIP    string
+	}{
+		{
+			name:       "RemoteAddr only",
+			remoteAddr: "192.168.1.1:12345",
+			expectedIP: "192.168.1.1",
+		},
+		{
+			name:          "X-Forwarded-For single IP",
+			remoteAddr:    "10.0.0.1:12345",
+			xForwardedFor: "203.0.113.1",
+			expectedIP:    "203.0.113.1",
+		},
+		{
+			name:          "X-Forwarded-For multiple IPs",
+			remoteAddr:    "10.0.0.1:12345",
+			xForwardedFor: "203.0.113.1, 10.0.0.2, 10.0.0.3",
+			expectedIP:    "203.0.113.1",
+		},
+		{
+			name:       "X-Real-IP",
+			remoteAddr: "10.0.0.1:12345",
+			xRealIP:    "203.0.113.1",
+			expectedIP: "203.0.113.1",
+		},
+		{
+			name:          "X-Forwarded-For takes precedence over X-Real-IP",
+			remoteAddr:    "10.0.0.1:12345",
+			xForwardedFor: "203.0.113.1",
+			xRealIP:       "203.0.113.2",
+			expectedIP:    "203.0.113.1",
+		},
+		{
+			name:       "IPv6 address",
+			remoteAddr: "[2001:db8::1]:12345",
+			expectedIP: "[2001:db8::1]",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := httptest.NewRequest("GET", "/test", nil)
+			req.RemoteAddr = tt.remoteAddr
+
+			if tt.xForwardedFor != "" {
+				req.Header.Set("X-Forwarded-For", tt.xForwardedFor)
+			}
+			if tt.xRealIP != "" {
+				req.Header.Set("X-Real-IP", tt.xRealIP)
+			}
+
+			ip := getClientIP(req)
+			if ip != tt.expectedIP {
+				t.Errorf("getClientIP() = %q, want %q", ip, tt.expectedIP)
+			}
+		})
+	}
+}
+
+func TestRateLimiterWithCustomKeyFunc(t *testing.T) {
+	rl := NewRateLimiter(1, 1)
+
+	// Use user ID as key
+	keyFunc := func(r *http.Request) string {
+		userID := r.Header.Get("X-User-ID")
+		if userID == "" {
+			return r.RemoteAddr
+		}
+		return "user:" + userID
+	}
+
+	handler := rl.MiddlewareWithKeyFunc(keyFunc)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	// User 1
+	req1 := httptest.NewRequest("GET", "/test", nil)
+	req1.Header.Set("X-User-ID", "user1")
+
+	// User 2
+	req2 := httptest.NewRequest("GET", "/test", nil)
+	req2.Header.Set("X-User-ID", "user2")
+
+	// Both users should succeed (different keys)
+	w1 := httptest.NewRecorder()
+	handler.ServeHTTP(w1, req1)
+
+	w2 := httptest.NewRecorder()
+	handler.ServeHTTP(w2, req2)
+
+	if w1.Code != http.StatusOK {
+		t.Errorf("User 1 request failed: got %d, want %d", w1.Code, http.StatusOK)
+	}
+
+	if w2.Code != http.StatusOK {
+		t.Errorf("User 2 request failed: got %d, want %d", w2.Code, http.StatusOK)
+	}
+
+	// User 1 second request should be rate limited
+	w1 = httptest.NewRecorder()
+	handler.ServeHTTP(w1, req1)
+
+	if w1.Code != http.StatusTooManyRequests {
+		t.Errorf("User 1 second request should be rate limited: got %d, want %d", w1.Code, http.StatusTooManyRequests)
+	}
+}
+
+func TestRateLimiter_GetTrackedIPs(t *testing.T) {
+	rl := NewRateLimiter(10, 10)
+
+	handler := rl.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	// Make requests from different IPs
+	ips := []string{"192.168.1.1", "192.168.1.2", "192.168.1.3"}
+	for _, ip := range ips {
+		req := httptest.NewRequest("GET", "/test", nil)
+		req.RemoteAddr = ip + ":12345"
+		w := httptest.NewRecorder()
+		handler.ServeHTTP(w, req)
+	}
+
+	// Check tracked IPs
+	trackedIPs := rl.GetTrackedIPs()
+	if len(trackedIPs) != len(ips) {
+		t.Errorf("len(trackedIPs) = %d, want %d", len(trackedIPs), len(ips))
+	}
+
+	// Verify all IPs are tracked
+	ipMap := make(map[string]bool)
+	for _, ip := range trackedIPs {
+		ipMap[ip] = true
+	}
+
+	for _, ip := range ips {
+		if !ipMap[ip] {
+			t.Errorf("IP %s should be tracked", ip)
+		}
+	}
+}
+
+func TestRateLimiter_GetRateLimitInfo(t *testing.T) {
+	rl := NewRateLimiter(10, 5)
+
+	handler := rl.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	// Make a request
+	req := httptest.NewRequest("GET", "/test", nil)
+	req.RemoteAddr = "192.168.1.1:12345"
+	w := httptest.NewRecorder()
+	handler.ServeHTTP(w, req)
+
+	// Get rate limit info
+	info := rl.GetRateLimitInfo("192.168.1.1")
+
+	if info.IP != "192.168.1.1" {
+		t.Errorf("IP = %q, want %q", info.IP, "192.168.1.1")
+	}
+
+	if info.Limit != 10.0 {
+		t.Errorf("Limit = %f, want 10.0", info.Limit)
+	}
+
+	if info.Burst != 5 {
+		t.Errorf("Burst = %d, want 5", info.Burst)
+	}
+
+	// Tokens should be less than burst after one request
+	if info.TokensRemaining >= float64(info.Burst) {
+		t.Errorf("TokensRemaining = %f, should be less than %d", info.TokensRemaining, info.Burst)
+	}
+}
+
+func TestRateLimiter_GetRateLimitInfo_UntrackedIP(t *testing.T) {
+	rl := NewRateLimiter(10, 5)
+
+	// Get info for untracked IP (should return default)
+	info := rl.GetRateLimitInfo("192.168.1.1")
+
+	if info.IP != "192.168.1.1" {
+		t.Errorf("IP = %q, want %q", info.IP, "192.168.1.1")
+	}
+
+	if info.TokensRemaining != float64(rl.burst) {
+		t.Errorf("TokensRemaining = %f, want %d (full burst)", info.TokensRemaining, rl.burst)
+	}
+}
+
+func TestRateLimiter_GetAllRateLimitInfo(t *testing.T) {
+	rl := NewRateLimiter(10, 10)
+
+	handler := rl.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	// Make requests from different IPs
+	ips := []string{"192.168.1.1", "192.168.1.2"}
+	for _, ip := range ips {
+		req := httptest.NewRequest("GET", "/test", nil)
+		req.RemoteAddr = ip + ":12345"
+		w := httptest.NewRecorder()
+		handler.ServeHTTP(w, req)
+	}
+
+	// Get all rate limit info
+	allInfo := rl.GetAllRateLimitInfo()
+
+	if len(allInfo) != len(ips) {
+		t.Errorf("len(allInfo) = %d, want %d", len(allInfo), len(ips))
+	}
+
+	// Verify each IP has info
+	for _, info := range allInfo {
+		found := false
+		for _, ip := range ips {
+			if info.IP == ip {
+				found = true
+				break
+			}
+		}
+		if !found {
+			t.Errorf("Unexpected IP in info: %s", info.IP)
+		}
+	}
+}
+
+func TestRateLimiter_StatsHandler(t *testing.T) {
+	rl := NewRateLimiter(10, 5)
+
+	handler := rl.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	// Make requests from different IPs
+	req1 := httptest.NewRequest("GET", "/test", nil)
+	req1.RemoteAddr = "192.168.1.1:12345"
+	w1 := httptest.NewRecorder()
+	handler.ServeHTTP(w1, req1)
+
+	req2 := httptest.NewRequest("GET", "/test", nil)
+	req2.RemoteAddr = "192.168.1.2:12345"
+	w2 := httptest.NewRecorder()
+	handler.ServeHTTP(w2, req2)
+
+	// Test stats handler (all IPs)
+	t.Run("AllIPs", func(t *testing.T) {
+		statsHandler := rl.StatsHandler()
+		req := httptest.NewRequest("GET", "/rate-limit-stats", nil)
+		w := httptest.NewRecorder()
+		statsHandler.ServeHTTP(w, req)
+
+		if w.Code != http.StatusOK {
+			t.Errorf("Status = %d, want %d", w.Code, http.StatusOK)
+		}
+
+		var stats map[string]interface{}
+		if err := json.Unmarshal(w.Body.Bytes(), &stats); err != nil {
+			t.Fatalf("Failed to parse response: %v", err)
+		}
+
+		if int(stats["total_tracked_ips"].(float64)) != 2 {
+			t.Errorf("total_tracked_ips = %v, want 2", stats["total_tracked_ips"])
+		}
+
+		config := stats["rate_limit_config"].(map[string]interface{})
+		if config["requests_per_second"].(float64) != 10.0 {
+			t.Errorf("requests_per_second = %v, want 10.0", config["requests_per_second"])
+		}
+	})
+
+	// Test stats handler (specific IP)
+	t.Run("SpecificIP", func(t *testing.T) {
+		statsHandler := rl.StatsHandler()
+		req := httptest.NewRequest("GET", "/rate-limit-stats?ip=192.168.1.1", nil)
+		w := httptest.NewRecorder()
+		statsHandler.ServeHTTP(w, req)
+
+		if w.Code != http.StatusOK {
+			t.Errorf("Status = %d, want %d", w.Code, http.StatusOK)
+		}
+
+		var info RateLimitInfo
+		if err := json.Unmarshal(w.Body.Bytes(), &info); err != nil {
+			t.Fatalf("Failed to parse response: %v", err)
+		}
+
+		if info.IP != "192.168.1.1" {
+			t.Errorf("IP = %q, want %q", info.IP, "192.168.1.1")
+		}
+	})
+}

pkg/middleware/sanitize.go

@@ -0,0 +1,251 @@
+package middleware
+
+import (
+	"html"
+	"net/http"
+	"regexp"
+	"strings"
+)
+
+// Sanitizer provides input sanitization beyond SQL injection protection
+type Sanitizer struct {
+	// StripHTML removes HTML tags from input
+	StripHTML bool
+
+	// EscapeHTML escapes HTML entities
+	EscapeHTML bool
+
+	// RemoveNullBytes removes null bytes from input
+	RemoveNullBytes bool
+
+	// RemoveControlChars removes control characters (except newline, carriage return, tab)
+	RemoveControlChars bool
+
+	// MaxStringLength limits individual string field length (0 = no limit)
+	MaxStringLength int
+
+	// BlockPatterns are regex patterns to block (e.g., script tags, SQL keywords)
+	BlockPatterns []*regexp.Regexp
+
+	// Custom sanitization function
+	CustomSanitizer func(string) string
+}
+
+// DefaultSanitizer returns a sanitizer with secure defaults
+func DefaultSanitizer() *Sanitizer {
+	return &Sanitizer{
+		StripHTML:          false, // Don't strip by default (breaks legitimate HTML content)
+		EscapeHTML:         true,  // Escape HTML entities to prevent XSS
+		RemoveNullBytes:    true,  // Remove null bytes (security best practice)
+		RemoveControlChars: true,  // Remove dangerous control characters
+		MaxStringLength:    0,     // No limit by default
+
+		// Block common XSS and injection patterns
+		BlockPatterns: []*regexp.Regexp{
+			regexp.MustCompile(`(?i)<script[^>]*>.*?</script>`), // Script tags
+			regexp.MustCompile(`(?i)javascript:`),               // JavaScript protocol
+			regexp.MustCompile(`(?i)on\w+\s*=`),                 // Event handlers (onclick, onerror, etc.)
+			regexp.MustCompile(`(?i)<iframe[^>]*>`),             // Iframes
+			regexp.MustCompile(`(?i)<object[^>]*>`),             // Objects
+			regexp.MustCompile(`(?i)<embed[^>]*>`),              // Embeds
+		},
+	}
+}
+
+// StrictSanitizer returns a sanitizer with very strict rules
+func StrictSanitizer() *Sanitizer {
+	s := DefaultSanitizer()
+	s.StripHTML = true
+	s.MaxStringLength = 10000
+	return s
+}
+
+// Sanitize sanitizes a string value
+func (s *Sanitizer) Sanitize(value string) string {
+	if value == "" {
+		return value
+	}
+
+	// Remove null bytes
+	if s.RemoveNullBytes {
+		value = strings.ReplaceAll(value, "\x00", "")
+	}
+
+	// Remove control characters
+	if s.RemoveControlChars {
+		value = removeControlCharacters(value)
+	}
+
+	// Check block patterns
+	for _, pattern := range s.BlockPatterns {
+		if pattern.MatchString(value) {
+			// Replace matched pattern with empty string
+			value = pattern.ReplaceAllString(value, "")
+		}
+	}
+
+	// Strip HTML tags
+	if s.StripHTML {
+		value = stripHTMLTags(value)
+	}
+
+	// Escape HTML entities
+	if s.EscapeHTML && !s.StripHTML {
+		value = html.EscapeString(value)
+	}
+
+	// Apply max length
+	if s.MaxStringLength > 0 && len(value) > s.MaxStringLength {
+		value = value[:s.MaxStringLength]
+	}
+
+	// Apply custom sanitizer
+	if s.CustomSanitizer != nil {
+		value = s.CustomSanitizer(value)
+	}
+
+	return value
+}
+
+// SanitizeMap sanitizes all string values in a map
+func (s *Sanitizer) SanitizeMap(data map[string]interface{}) map[string]interface{} {
+	result := make(map[string]interface{})
+	for key, value := range data {
+		result[key] = s.sanitizeValue(value)
+	}
+	return result
+}
+
+// sanitizeValue recursively sanitizes values
+func (s *Sanitizer) sanitizeValue(value interface{}) interface{} {
+	switch v := value.(type) {
+	case string:
+		return s.Sanitize(v)
+	case map[string]interface{}:
+		return s.SanitizeMap(v)
+	case []interface{}:
+		result := make([]interface{}, len(v))
+		for i, item := range v {
+			result[i] = s.sanitizeValue(item)
+		}
+		return result
+	default:
+		return value
+	}
+}
+
+// Middleware returns an HTTP middleware that sanitizes request headers and query params
+// Note: Body sanitization should be done at the application level after parsing
+func (s *Sanitizer) Middleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Sanitize query parameters
+		if r.URL.RawQuery != "" {
+			q := r.URL.Query()
+			sanitized := false
+			for key, values := range q {
+				for i, value := range values {
+					sanitizedValue := s.Sanitize(value)
+					if sanitizedValue != value {
+						values[i] = sanitizedValue
+						sanitized = true
+					}
+				}
+				if sanitized {
+					q[key] = values
+				}
+			}
+			if sanitized {
+				r.URL.RawQuery = q.Encode()
+			}
+		}
+
+		// Sanitize specific headers (User-Agent, Referer, etc.)
+		dangerousHeaders := []string{
+			"User-Agent",
+			"Referer",
+			"X-Forwarded-For",
+			"X-Real-IP",
+		}
+
+		for _, header := range dangerousHeaders {
+			if value := r.Header.Get(header); value != "" {
+				sanitized := s.Sanitize(value)
+				if sanitized != value {
+					r.Header.Set(header, sanitized)
+				}
+			}
+		}
+
+		next.ServeHTTP(w, r)
+	})
+}
+
+// Helper functions
+
+// removeControlCharacters removes control characters except \n, \r, \t
+func removeControlCharacters(s string) string {
+	var result strings.Builder
+	for _, r := range s {
+		// Keep newline, carriage return, tab, and non-control characters
+		if r == '\n' || r == '\r' || r == '\t' || r >= 32 {
+			result.WriteRune(r)
+		}
+	}
+	return result.String()
+}
+
+// stripHTMLTags removes HTML tags from a string
+func stripHTMLTags(s string) string {
+	// Simple regex to remove HTML tags
+	re := regexp.MustCompile(`<[^>]*>`)
+	return re.ReplaceAllString(s, "")
+}
+
+// Common sanitization patterns
+
+// SanitizeFilename sanitizes a filename
+func SanitizeFilename(filename string) string {
+	// Remove path traversal attempts
+	filename = strings.ReplaceAll(filename, "..", "")
+	filename = strings.ReplaceAll(filename, "/", "")
+	filename = strings.ReplaceAll(filename, "\\", "")
+
+	// Remove null bytes
+	filename = strings.ReplaceAll(filename, "\x00", "")
+
+	// Limit length
+	if len(filename) > 255 {
+		filename = filename[:255]
+	}
+
+	return filename
+}
+
+// SanitizeEmail performs basic email sanitization
+func SanitizeEmail(email string) string {
+	email = strings.TrimSpace(strings.ToLower(email))
+
+	// Remove dangerous characters
+	email = strings.ReplaceAll(email, "\x00", "")
+	email = removeControlCharacters(email)
+
+	return email
+}
+
+// SanitizeURL performs basic URL sanitization
+func SanitizeURL(url string) string {
+	url = strings.TrimSpace(url)
+
+	// Remove null bytes
+	url = strings.ReplaceAll(url, "\x00", "")
+
+	// Block javascript: and data: protocols
+	if strings.HasPrefix(strings.ToLower(url), "javascript:") {
+		return ""
+	}
+	if strings.HasPrefix(strings.ToLower(url), "data:") {
+		return ""
+	}
+
+	return url
+}

pkg/middleware/sanitize_test.go

@@ -0,0 +1,273 @@
+package middleware
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestSanitizeXSS(t *testing.T) {
+	sanitizer := DefaultSanitizer()
+
+	tests := []struct {
+		name     string
+		input    string
+		contains string // String that should NOT be in output
+	}{
+		{
+			name:     "Script tag",
+			input:    "<script>alert(1)</script>",
+			contains: "<script>",
+		},
+		{
+			name:     "JavaScript protocol",
+			input:    "javascript:alert(1)",
+			contains: "javascript:",
+		},
+		{
+			name:     "Event handler",
+			input:    "<img onerror='alert(1)'>",
+			contains: "onerror=",
+		},
+		{
+			name:     "Iframe",
+			input:    "<iframe src='evil.com'></iframe>",
+			contains: "<iframe",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := sanitizer.Sanitize(tt.input)
+			if result == tt.input {
+				t.Errorf("Sanitize() did not modify input: %q", tt.input)
+			}
+		})
+	}
+}
+
+func TestSanitizeNullBytes(t *testing.T) {
+	sanitizer := DefaultSanitizer()
+
+	input := "hello\x00world"
+	result := sanitizer.Sanitize(input)
+
+	if result == input {
+		t.Error("Null bytes should be removed")
+	}
+
+	if len(result) >= len(input) {
+		t.Errorf("Result length should be less than input: got %d, input %d", len(result), len(input))
+	}
+}
+
+func TestSanitizeControlCharacters(t *testing.T) {
+	sanitizer := DefaultSanitizer()
+
+	// Include various control characters
+	input := "hello\x01\x02world\x1F"
+	result := sanitizer.Sanitize(input)
+
+	if result == input {
+		t.Error("Control characters should be removed")
+	}
+
+	// Newlines, tabs, carriage returns should be preserved
+	input2 := "hello\nworld\t\r"
+	result2 := sanitizer.Sanitize(input2)
+
+	if result2 != input2 {
+		t.Errorf("Safe control characters should be preserved: got %q, want %q", result2, input2)
+	}
+}
+
+func TestSanitizeMap(t *testing.T) {
+	sanitizer := DefaultSanitizer()
+
+	input := map[string]interface{}{
+		"name":  "<script>alert(1)</script>John",
+		"email": "test@example.com",
+		"nested": map[string]interface{}{
+			"bio": "<iframe src='evil.com'>Bio</iframe>",
+		},
+	}
+
+	result := sanitizer.SanitizeMap(input)
+
+	// Check that script tag was removed/escaped
+	name, ok := result["name"].(string)
+	if !ok || name == input["name"] {
+		t.Error("Name should be sanitized")
+	}
+
+	// Check nested map
+	nested, ok := result["nested"].(map[string]interface{})
+	if !ok {
+		t.Fatal("Nested should still be a map")
+	}
+
+	bio, ok := nested["bio"].(string)
+	if !ok || bio == input["nested"].(map[string]interface{})["bio"] {
+		t.Error("Nested bio should be sanitized")
+	}
+}
+
+func TestSanitizeMiddleware(t *testing.T) {
+	sanitizer := DefaultSanitizer()
+
+	handler := sanitizer.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Check that query param was sanitized
+		param := r.URL.Query().Get("q")
+		if param == "<script>alert(1)</script>" {
+			t.Error("Query param should be sanitized")
+		}
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	req := httptest.NewRequest("GET", "/test?q=<script>alert(1)</script>", nil)
+	w := httptest.NewRecorder()
+
+	handler.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Handler failed: got %d, want %d", w.Code, http.StatusOK)
+	}
+}
+
+func TestSanitizeFilename(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		contains string // String that should NOT be in output
+	}{
+		{
+			name:     "Path traversal",
+			input:    "../../../etc/passwd",
+			contains: "..",
+		},
+		{
+			name:     "Absolute path",
+			input:    "/etc/passwd",
+			contains: "/",
+		},
+		{
+			name:     "Windows path",
+			input:    "..\\..\\windows\\system32",
+			contains: "\\",
+		},
+		{
+			name:     "Null byte",
+			input:    "file\x00.txt",
+			contains: "\x00",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := SanitizeFilename(tt.input)
+			if result == tt.input {
+				t.Errorf("SanitizeFilename() did not modify input: %q", tt.input)
+			}
+		})
+	}
+}
+
+func TestSanitizeEmail(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "Uppercase",
+			input:    "TEST@EXAMPLE.COM",
+			expected: "test@example.com",
+		},
+		{
+			name:     "Whitespace",
+			input:    "  test@example.com  ",
+			expected: "test@example.com",
+		},
+		{
+			name:     "Null bytes",
+			input:    "test\x00@example.com",
+			expected: "test@example.com",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := SanitizeEmail(tt.input)
+			if result != tt.expected {
+				t.Errorf("SanitizeEmail() = %q, want %q", result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestSanitizeURL(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "JavaScript protocol",
+			input:    "javascript:alert(1)",
+			expected: "",
+		},
+		{
+			name:     "Data protocol",
+			input:    "data:text/html,<script>alert(1)</script>",
+			expected: "",
+		},
+		{
+			name:     "Valid HTTP URL",
+			input:    "https://example.com",
+			expected: "https://example.com",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := SanitizeURL(tt.input)
+			if result != tt.expected {
+				t.Errorf("SanitizeURL() = %q, want %q", result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestStrictSanitizer(t *testing.T) {
+	sanitizer := StrictSanitizer()
+
+	input := "<b>Bold text</b> with <script>alert(1)</script>"
+	result := sanitizer.Sanitize(input)
+
+	// Should strip ALL HTML tags
+	if result == input {
+		t.Error("Strict sanitizer should modify input")
+	}
+
+	// Should not contain any HTML tags
+	if len(result) > 0 && (result[0] == '<' || result[len(result)-1] == '>') {
+		t.Error("Result should not contain HTML tags")
+	}
+}
+
+func TestMaxStringLength(t *testing.T) {
+	sanitizer := &Sanitizer{
+		MaxStringLength: 10,
+	}
+
+	input := "This is a very long string that exceeds the maximum length"
+	result := sanitizer.Sanitize(input)
+
+	if len(result) != 10 {
+		t.Errorf("Result length = %d, want 10", len(result))
+	}
+
+	if result != input[:10] {
+		t.Errorf("Result = %q, want %q", result, input[:10])
+	}
+}

pkg/middleware/sizelimit.go

@@ -0,0 +1,70 @@
+package middleware
+
+import (
+	"fmt"
+	"net/http"
+)
+
+const (
+	// DefaultMaxRequestSize is the default maximum request body size (10MB)
+	DefaultMaxRequestSize = 10 * 1024 * 1024 // 10MB
+
+	// MaxRequestSizeHeader is the header name for max request size
+	MaxRequestSizeHeader = "X-Max-Request-Size"
+)
+
+// RequestSizeLimiter limits the size of request bodies
+type RequestSizeLimiter struct {
+	maxSize int64
+}
+
+// NewRequestSizeLimiter creates a new request size limiter
+// maxSize is in bytes. If 0, uses DefaultMaxRequestSize (10MB)
+func NewRequestSizeLimiter(maxSize int64) *RequestSizeLimiter {
+	if maxSize <= 0 {
+		maxSize = DefaultMaxRequestSize
+	}
+	return &RequestSizeLimiter{
+		maxSize: maxSize,
+	}
+}
+
+// Middleware returns an HTTP middleware that enforces request size limits
+func (rsl *RequestSizeLimiter) Middleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Set max bytes reader on the request body
+		r.Body = http.MaxBytesReader(w, r.Body, rsl.maxSize)
+
+		// Add informational header
+		w.Header().Set(MaxRequestSizeHeader, fmt.Sprintf("%d", rsl.maxSize))
+
+		next.ServeHTTP(w, r)
+	})
+}
+
+// MiddlewareWithCustomSize returns middleware with a custom size limit function
+// This allows different size limits based on the request
+func (rsl *RequestSizeLimiter) MiddlewareWithCustomSize(sizeFunc func(*http.Request) int64) func(http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			maxSize := sizeFunc(r)
+			if maxSize <= 0 {
+				maxSize = rsl.maxSize
+			}
+
+			r.Body = http.MaxBytesReader(w, r.Body, maxSize)
+			w.Header().Set(MaxRequestSizeHeader, fmt.Sprintf("%d", maxSize))
+
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
+// Common size limits
+const (
+	Size1MB   = 1 * 1024 * 1024
+	Size5MB   = 5 * 1024 * 1024
+	Size10MB  = 10 * 1024 * 1024
+	Size50MB  = 50 * 1024 * 1024
+	Size100MB = 100 * 1024 * 1024
+)

pkg/middleware/sizelimit_test.go

@@ -0,0 +1,126 @@
+package middleware
+
+import (
+	"bytes"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestRequestSizeLimiter(t *testing.T) {
+	// 1KB limit
+	limiter := NewRequestSizeLimiter(1024)
+
+	handler := limiter.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Try to read body
+		_, err := io.ReadAll(r.Body)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusRequestEntityTooLarge)
+			return
+		}
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	// Small request (should succeed)
+	t.Run("SmallRequest", func(t *testing.T) {
+		body := bytes.NewReader(make([]byte, 512)) // 512 bytes
+		req := httptest.NewRequest("POST", "/test", body)
+		w := httptest.NewRecorder()
+
+		handler.ServeHTTP(w, req)
+
+		if w.Code != http.StatusOK {
+			t.Errorf("Small request failed: got %d, want %d", w.Code, http.StatusOK)
+		}
+
+		// Check header
+		if maxSize := w.Header().Get(MaxRequestSizeHeader); maxSize != "1024" {
+			t.Errorf("MaxRequestSizeHeader = %q, want %q", maxSize, "1024")
+		}
+	})
+
+	// Large request (should fail)
+	t.Run("LargeRequest", func(t *testing.T) {
+		body := bytes.NewReader(make([]byte, 2048)) // 2KB
+		req := httptest.NewRequest("POST", "/test", body)
+		w := httptest.NewRecorder()
+
+		handler.ServeHTTP(w, req)
+
+		if w.Code != http.StatusRequestEntityTooLarge {
+			t.Errorf("Large request should fail: got %d, want %d", w.Code, http.StatusRequestEntityTooLarge)
+		}
+	})
+}
+
+func TestRequestSizeLimiterDefault(t *testing.T) {
+	// Default limiter (10MB)
+	limiter := NewRequestSizeLimiter(0)
+
+	handler := limiter.Middleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	req := httptest.NewRequest("POST", "/test", bytes.NewReader(make([]byte, 1024)))
+	w := httptest.NewRecorder()
+
+	handler.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Request failed: got %d, want %d", w.Code, http.StatusOK)
+	}
+
+	// Check default size
+	if maxSize := w.Header().Get(MaxRequestSizeHeader); maxSize != "10485760" {
+		t.Errorf("Default MaxRequestSizeHeader = %q, want %q", maxSize, "10485760")
+	}
+}
+
+func TestRequestSizeLimiterWithCustomSize(t *testing.T) {
+	limiter := NewRequestSizeLimiter(1024)
+
+	// Premium users get 10MB, regular users get 1KB
+	sizeFunc := func(r *http.Request) int64 {
+		if r.Header.Get("X-User-Tier") == "premium" {
+			return Size10MB
+		}
+		return 1024
+	}
+
+	handler := limiter.MiddlewareWithCustomSize(sizeFunc)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, err := io.ReadAll(r.Body)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusRequestEntityTooLarge)
+			return
+		}
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	// Regular user with large request (should fail)
+	t.Run("RegularUserLargeRequest", func(t *testing.T) {
+		body := bytes.NewReader(make([]byte, 2048))
+		req := httptest.NewRequest("POST", "/test", body)
+		w := httptest.NewRecorder()
+
+		handler.ServeHTTP(w, req)
+
+		if w.Code != http.StatusRequestEntityTooLarge {
+			t.Errorf("Regular user large request should fail: got %d, want %d", w.Code, http.StatusRequestEntityTooLarge)
+		}
+	})
+
+	// Premium user with large request (should succeed)
+	t.Run("PremiumUserLargeRequest", func(t *testing.T) {
+		body := bytes.NewReader(make([]byte, 2048))
+		req := httptest.NewRequest("POST", "/test", body)
+		req.Header.Set("X-User-Tier", "premium")
+		w := httptest.NewRecorder()
+
+		handler.ServeHTTP(w, req)
+
+		if w.Code != http.StatusOK {
+			t.Errorf("Premium user large request failed: got %d, want %d", w.Code, http.StatusOK)
+		}
+	})
+}

pkg/modelregistry/model_registry.go

@@ -28,8 +28,14 @@ func NewModelRegistry() *DefaultModelRegistry {
 	}
 }
 
+func GetDefaultRegistry() *DefaultModelRegistry {
+	return defaultRegistry
+}
+
 func SetDefaultRegistry(registry *DefaultModelRegistry) {
 	registriesMutex.Lock()
+	defer registriesMutex.Unlock()
+
 	foundAt := -1
 	for idx, r := range registries {
 		if r == defaultRegistry {
@@ -43,9 +49,6 @@ func SetDefaultRegistry(registry *DefaultModelRegistry) {
 	} else {
 		registries = append([]*DefaultModelRegistry{registry}, registries...)
 	}
-
-	defer registriesMutex.Unlock()
-
 }
 
 // AddRegistry adds a registry to the global list of registries

pkg/openapi/README.md

@@ -0,0 +1,321 @@
+# OpenAPI Generator for ResolveSpec
+
+This package provides automatic OpenAPI 3.0 specification generation for ResolveSpec, RestheadSpec, and FuncSpec API frameworks.
+
+## Features
+
+- **Automatic Schema Generation**: Generates OpenAPI schemas from Go struct models
+- **Multiple Framework Support**: Works with RestheadSpec, ResolveSpec, and FuncSpec
+- **Dynamic Endpoint Discovery**: Automatically discovers all registered models and generates paths
+- **Query Parameter Access**: Access spec via `?openapi` on any endpoint or via `/openapi`
+- **Comprehensive Documentation**: Includes all request/response schemas, parameters, and security schemes
+
+## Quick Start
+
+### RestheadSpec Example
+
+```go
+import (
+    "github.com/bitechdev/ResolveSpec/pkg/openapi"
+    "github.com/bitechdev/ResolveSpec/pkg/restheadspec"
+    "github.com/gorilla/mux"
+)
+
+func main() {
+    // 1. Create handler
+    handler := restheadspec.NewHandlerWithGORM(db)
+
+    // 2. Register models
+    handler.registry.RegisterModel("public.users", User{})
+    handler.registry.RegisterModel("public.products", Product{})
+
+    // 3. Configure OpenAPI generator
+    handler.SetOpenAPIGenerator(func() (string, error) {
+        generator := openapi.NewGenerator(openapi.GeneratorConfig{
+            Title:       "My API",
+            Description: "API documentation",
+            Version:     "1.0.0",
+            BaseURL:     "http://localhost:8080",
+            Registry:    handler.registry.(*modelregistry.DefaultModelRegistry),
+            IncludeRestheadSpec: true,
+            IncludeResolveSpec:  false,
+            IncludeFuncSpec:     false,
+        })
+        return generator.GenerateJSON()
+    })
+
+    // 4. Setup routes (automatically includes /openapi endpoint)
+    router := mux.NewRouter()
+    restheadspec.SetupMuxRoutes(router, handler, nil)
+
+    // Start server
+    http.ListenAndServe(":8080", router)
+}
+```
+
+### ResolveSpec Example
+
+```go
+func main() {
+    // 1. Create handler
+    handler := resolvespec.NewHandlerWithGORM(db)
+
+    // 2. Register models
+    handler.RegisterModel("public", "users", User{})
+    handler.RegisterModel("public", "products", Product{})
+
+    // 3. Configure OpenAPI generator
+    handler.SetOpenAPIGenerator(func() (string, error) {
+        generator := openapi.NewGenerator(openapi.GeneratorConfig{
+            Title:       "My API",
+            Version:     "1.0.0",
+            Registry:    handler.registry.(*modelregistry.DefaultModelRegistry),
+            IncludeResolveSpec: true,
+        })
+        return generator.GenerateJSON()
+    })
+
+    // 4. Setup routes
+    router := mux.NewRouter()
+    resolvespec.SetupMuxRoutes(router, handler, nil)
+
+    http.ListenAndServe(":8080", router)
+}
+```
+
+## Accessing the OpenAPI Specification
+
+Once configured, the OpenAPI spec is available in two ways:
+
+### 1. Global `/openapi` Endpoint
+
+```bash
+curl http://localhost:8080/openapi
+```
+
+Returns the complete OpenAPI specification for all registered models.
+
+### 2. Query Parameter on Any Endpoint
+
+```bash
+# RestheadSpec
+curl http://localhost:8080/public/users?openapi
+
+# ResolveSpec
+curl http://localhost:8080/resolve/public/users?openapi
+```
+
+Returns the same OpenAPI specification as `/openapi`.
+
+## Generated Endpoints
+
+### RestheadSpec
+
+For each registered model (e.g., `public.users`), the following paths are generated:
+
+- `GET /public/users` - List records with header-based filtering
+- `POST /public/users` - Create a new record
+- `GET /public/users/{id}` - Get a single record
+- `PUT /public/users/{id}` - Update a record
+- `PATCH /public/users/{id}` - Partially update a record
+- `DELETE /public/users/{id}` - Delete a record
+- `GET /public/users/metadata` - Get table metadata
+- `OPTIONS /public/users` - CORS preflight
+
+### ResolveSpec
+
+For each registered model (e.g., `public.users`), the following paths are generated:
+
+- `POST /resolve/public/users` - Execute operations (read, create, meta)
+- `POST /resolve/public/users/{id}` - Execute operations (update, delete)
+- `GET /resolve/public/users` - Get metadata
+- `OPTIONS /resolve/public/users` - CORS preflight
+
+## Schema Generation
+
+The generator automatically extracts information from your Go struct tags:
+
+```go
+type User struct {
+    ID        int       `json:"id" gorm:"primaryKey" description:"User ID"`
+    Name      string    `json:"name" gorm:"not null" description:"User's full name"`
+    Email     string    `json:"email" gorm:"unique" description:"Email address"`
+    CreatedAt time.Time `json:"created_at" description:"Creation timestamp"`
+    Roles     []string  `json:"roles" description:"User roles"`
+}
+```
+
+This generates an OpenAPI schema with:
+- Property names from `json` tags
+- Required fields from `gorm:"not null"` and non-pointer types
+- Descriptions from `description` tags
+- Proper type mappings (int → integer, time.Time → string with format: date-time, etc.)
+
+## RestheadSpec Headers
+
+The generator documents all RestheadSpec HTTP headers:
+
+- `X-Filters` - JSON array of filter conditions
+- `X-Columns` - Comma-separated columns to select
+- `X-Sort` - JSON array of sort specifications
+- `X-Limit` - Maximum records to return
+- `X-Offset` - Records to skip
+- `X-Preload` - Relations to eager load
+- `X-Expand` - Relations to expand (LEFT JOIN)
+- `X-Distinct` - Enable DISTINCT queries
+- `X-Response-Format` - Response format (detail, simple, syncfusion)
+- `X-Clean-JSON` - Remove null/empty fields
+- `X-Custom-SQL-Where` - Custom WHERE clause (AND)
+- `X-Custom-SQL-Or` - Custom WHERE clause (OR)
+
+## ResolveSpec Request Body
+
+The generator documents the ResolveSpec request body structure:
+
+```json
+{
+  "operation": "read",
+  "data": {},
+  "id": 123,
+  "options": {
+    "limit": 10,
+    "offset": 0,
+    "filters": [
+      {"column": "status", "operator": "eq", "value": "active"}
+    ],
+    "sort": [
+      {"column": "created_at", "direction": "desc"}
+    ]
+  }
+}
+```
+
+## Security Schemes
+
+The generator automatically includes common security schemes:
+
+- **BearerAuth**: JWT Bearer token authentication
+- **SessionToken**: Session token in Authorization header
+- **CookieAuth**: Cookie-based session authentication
+- **HeaderAuth**: Header-based user authentication (X-User-ID)
+
+## FuncSpec Custom Endpoints
+
+For FuncSpec, you can manually register custom SQL endpoints:
+
+```go
+funcSpecEndpoints := map[string]openapi.FuncSpecEndpoint{
+    "/api/reports/sales": {
+        Path:        "/api/reports/sales",
+        Method:      "GET",
+        Summary:     "Get sales report",
+        Description: "Returns sales data for specified date range",
+        SQLQuery:    "SELECT * FROM sales WHERE date BETWEEN [start_date] AND [end_date]",
+        Parameters:  []string{"start_date", "end_date"},
+    },
+}
+
+generator := openapi.NewGenerator(openapi.GeneratorConfig{
+    // ... other config
+    IncludeFuncSpec:   true,
+    FuncSpecEndpoints: funcSpecEndpoints,
+})
+```
+
+## Combining Multiple Frameworks
+
+You can generate a unified OpenAPI spec that includes multiple frameworks:
+
+```go
+generator := openapi.NewGenerator(openapi.GeneratorConfig{
+    Title:       "Unified API",
+    Version:     "1.0.0",
+    Registry:    sharedRegistry,
+    IncludeRestheadSpec: true,
+    IncludeResolveSpec:  true,
+    IncludeFuncSpec:     true,
+    FuncSpecEndpoints:   funcSpecEndpoints,
+})
+```
+
+This will generate a complete spec with all endpoints from all frameworks.
+
+## Advanced Customization
+
+You can customize the generated spec further:
+
+```go
+handler.SetOpenAPIGenerator(func() (string, error) {
+    generator := openapi.NewGenerator(config)
+
+    // Generate initial spec
+    spec, err := generator.Generate()
+    if err != nil {
+        return "", err
+    }
+
+    // Add contact information
+    spec.Info.Contact = &openapi.Contact{
+        Name:  "API Support",
+        Email: "support@example.com",
+        URL:   "https://example.com/support",
+    }
+
+    // Add additional servers
+    spec.Servers = append(spec.Servers, openapi.Server{
+        URL:         "https://staging.example.com",
+        Description: "Staging Server",
+    })
+
+    // Convert back to JSON
+    data, _ := json.MarshalIndent(spec, "", "  ")
+    return string(data), nil
+})
+```
+
+## Using with Swagger UI
+
+You can serve the generated OpenAPI spec with Swagger UI:
+
+1. Get the spec from `/openapi`
+2. Load it in Swagger UI at `https://petstore.swagger.io/`
+3. Or self-host Swagger UI and point it to your `/openapi` endpoint
+
+Example with self-hosted Swagger UI:
+
+```go
+// Serve Swagger UI static files
+router.PathPrefix("/swagger/").Handler(
+    http.StripPrefix("/swagger/", http.FileServer(http.Dir("./swagger-ui"))),
+)
+
+// Configure Swagger UI to use /openapi
+```
+
+## Testing
+
+You can test the OpenAPI endpoint:
+
+```bash
+# Get the full spec
+curl http://localhost:8080/openapi | jq
+
+# Validate with openapi-generator
+openapi-generator validate -i http://localhost:8080/openapi
+
+# Generate client SDKs
+openapi-generator generate -i http://localhost:8080/openapi -g typescript-fetch -o ./client
+```
+
+## Complete Example
+
+See `example.go` in this package for complete, runnable examples including:
+- Basic RestheadSpec setup
+- Basic ResolveSpec setup
+- Combining both frameworks
+- Adding FuncSpec endpoints
+- Advanced customization
+
+## License
+
+Part of the ResolveSpec project.

pkg/openapi/example.go

@@ -0,0 +1,236 @@
+package openapi
+
+import (
+	"github.com/gorilla/mux"
+	"gorm.io/gorm"
+
+	"github.com/bitechdev/ResolveSpec/pkg/modelregistry"
+	"github.com/bitechdev/ResolveSpec/pkg/resolvespec"
+	"github.com/bitechdev/ResolveSpec/pkg/restheadspec"
+)
+
+// ExampleRestheadSpec shows how to configure OpenAPI generation for RestheadSpec
+func ExampleRestheadSpec(db *gorm.DB) {
+	// 1. Create registry and register models
+	registry := modelregistry.NewModelRegistry()
+	// registry.RegisterModel("public.users", User{})
+	// registry.RegisterModel("public.products", Product{})
+
+	// 2. Create handler with custom registry
+	// import "github.com/bitechdev/ResolveSpec/pkg/common/adapters/database"
+	// gormAdapter := database.NewGormAdapter(db)
+	// handler := restheadspec.NewHandler(gormAdapter, registry)
+	// Or use the convenience function (creates its own registry):
+	handler := restheadspec.NewHandlerWithGORM(db)
+
+	// 3. Configure OpenAPI generator
+	handler.SetOpenAPIGenerator(func() (string, error) {
+		generator := NewGenerator(GeneratorConfig{
+			Title:               "My API",
+			Description:         "API documentation for my application",
+			Version:             "1.0.0",
+			BaseURL:             "http://localhost:8080",
+			Registry:            registry,
+			IncludeRestheadSpec: true,
+			IncludeResolveSpec:  false,
+			IncludeFuncSpec:     false,
+		})
+		return generator.GenerateJSON()
+	})
+
+	// 4. Setup routes (includes /openapi endpoint)
+	router := mux.NewRouter()
+	restheadspec.SetupMuxRoutes(router, handler, nil)
+
+	// Now the following endpoints are available:
+	// GET /openapi                     - Full OpenAPI spec
+	// GET /public/users?openapi        - OpenAPI spec
+	// GET /public/products?openapi     - OpenAPI spec
+	// etc.
+}
+
+// ExampleResolveSpec shows how to configure OpenAPI generation for ResolveSpec
+func ExampleResolveSpec(db *gorm.DB) {
+	// 1. Create registry and register models
+	registry := modelregistry.NewModelRegistry()
+	// registry.RegisterModel("public.users", User{})
+	// registry.RegisterModel("public.products", Product{})
+
+	// 2. Create handler with custom registry
+	// import "github.com/bitechdev/ResolveSpec/pkg/common/adapters/database"
+	// gormAdapter := database.NewGormAdapter(db)
+	// handler := resolvespec.NewHandler(gormAdapter, registry)
+	// Or use the convenience function (creates its own registry):
+	handler := resolvespec.NewHandlerWithGORM(db)
+	// Note: handler.RegisterModel("schema", "entity", model) can be used
+
+	// 3. Configure OpenAPI generator
+	handler.SetOpenAPIGenerator(func() (string, error) {
+		generator := NewGenerator(GeneratorConfig{
+			Title:               "My API",
+			Description:         "API documentation for my application",
+			Version:             "1.0.0",
+			BaseURL:             "http://localhost:8080",
+			Registry:            registry,
+			IncludeRestheadSpec: false,
+			IncludeResolveSpec:  true,
+			IncludeFuncSpec:     false,
+		})
+		return generator.GenerateJSON()
+	})
+
+	// 4. Setup routes (includes /openapi endpoint)
+	router := mux.NewRouter()
+	resolvespec.SetupMuxRoutes(router, handler, nil)
+
+	// Now the following endpoints are available:
+	// GET /openapi                          - Full OpenAPI spec
+	// POST /resolve/public/users?openapi    - OpenAPI spec
+	// POST /resolve/public/products?openapi - OpenAPI spec
+	// etc.
+}
+
+// ExampleBothSpecs shows how to combine both RestheadSpec and ResolveSpec
+func ExampleBothSpecs(db *gorm.DB) {
+	// Create shared registry
+	sharedRegistry := modelregistry.NewModelRegistry()
+	// Register models once
+	// sharedRegistry.RegisterModel("public.users", User{})
+	// sharedRegistry.RegisterModel("public.products", Product{})
+
+	// Create handlers - they will have separate registries initially
+	restheadHandler := restheadspec.NewHandlerWithGORM(db)
+	resolveHandler := resolvespec.NewHandlerWithGORM(db)
+
+	// Note: If you want to use a shared registry, create handlers manually:
+	// import "github.com/bitechdev/ResolveSpec/pkg/common/adapters/database"
+	// gormAdapter := database.NewGormAdapter(db)
+	// restheadHandler := restheadspec.NewHandler(gormAdapter, sharedRegistry)
+	// resolveHandler := resolvespec.NewHandler(gormAdapter, sharedRegistry)
+
+	// Configure OpenAPI generator for both
+	generatorFunc := func() (string, error) {
+		generator := NewGenerator(GeneratorConfig{
+			Title:               "My Unified API",
+			Description:         "Complete API documentation with both RestheadSpec and ResolveSpec endpoints",
+			Version:             "1.0.0",
+			BaseURL:             "http://localhost:8080",
+			Registry:            sharedRegistry,
+			IncludeRestheadSpec: true,
+			IncludeResolveSpec:  true,
+			IncludeFuncSpec:     false,
+		})
+		return generator.GenerateJSON()
+	}
+
+	restheadHandler.SetOpenAPIGenerator(generatorFunc)
+	resolveHandler.SetOpenAPIGenerator(generatorFunc)
+
+	// Setup routes
+	router := mux.NewRouter()
+	restheadspec.SetupMuxRoutes(router, restheadHandler, nil)
+
+	// Add ResolveSpec routes under /resolve prefix
+	resolveRouter := router.PathPrefix("/resolve").Subrouter()
+	resolvespec.SetupMuxRoutes(resolveRouter, resolveHandler, nil)
+
+	// Now you have both styles of API available:
+	// GET /openapi                              - Full OpenAPI spec (both styles)
+	// GET /public/users                         - RestheadSpec list endpoint
+	// POST /resolve/public/users                - ResolveSpec operation endpoint
+	// GET /public/users?openapi                 - OpenAPI spec
+	// POST /resolve/public/users?openapi        - OpenAPI spec
+}
+
+// ExampleWithFuncSpec shows how to add FuncSpec endpoints to OpenAPI
+func ExampleWithFuncSpec() {
+	// FuncSpec endpoints need to be registered manually since they don't use model registry
+	generatorFunc := func() (string, error) {
+		funcSpecEndpoints := map[string]FuncSpecEndpoint{
+			"/api/reports/sales": {
+				Path:        "/api/reports/sales",
+				Method:      "GET",
+				Summary:     "Get sales report",
+				Description: "Returns sales data for the specified date range",
+				SQLQuery:    "SELECT * FROM sales WHERE date BETWEEN [start_date] AND [end_date]",
+				Parameters:  []string{"start_date", "end_date"},
+			},
+			"/api/analytics/users": {
+				Path:        "/api/analytics/users",
+				Method:      "GET",
+				Summary:     "Get user analytics",
+				Description: "Returns user activity analytics",
+				SQLQuery:    "SELECT * FROM user_analytics WHERE user_id = [user_id]",
+				Parameters:  []string{"user_id"},
+			},
+		}
+
+		generator := NewGenerator(GeneratorConfig{
+			Title:               "My API with Custom Queries",
+			Description:         "API with FuncSpec custom SQL endpoints",
+			Version:             "1.0.0",
+			BaseURL:             "http://localhost:8080",
+			Registry:            modelregistry.NewModelRegistry(),
+			IncludeRestheadSpec: false,
+			IncludeResolveSpec:  false,
+			IncludeFuncSpec:     true,
+			FuncSpecEndpoints:   funcSpecEndpoints,
+		})
+		return generator.GenerateJSON()
+	}
+
+	// Use this generator function with your handlers
+	_ = generatorFunc
+}
+
+// ExampleCustomization shows advanced customization options
+func ExampleCustomization() {
+	// Create registry and register models with descriptions using struct tags
+	registry := modelregistry.NewModelRegistry()
+
+	// type User struct {
+	//     ID    int    `json:"id" gorm:"primaryKey" description:"Unique user identifier"`
+	//     Name  string `json:"name" description:"User's full name"`
+	//     Email string `json:"email" gorm:"unique" description:"User's email address"`
+	// }
+	// registry.RegisterModel("public.users", User{})
+
+	// Advanced configuration - create generator function
+	generatorFunc := func() (string, error) {
+		generator := NewGenerator(GeneratorConfig{
+			Title:               "My Advanced API",
+			Description:         "Comprehensive API documentation with custom configuration",
+			Version:             "2.1.0",
+			BaseURL:             "https://api.myapp.com",
+			Registry:            registry,
+			IncludeRestheadSpec: true,
+			IncludeResolveSpec:  true,
+			IncludeFuncSpec:     false,
+		})
+
+		// Generate the spec
+		// spec, err := generator.Generate()
+		// if err != nil {
+		//     return "", err
+		// }
+
+		// Customize the spec further if needed
+		// spec.Info.Contact = &Contact{
+		//     Name:  "API Support",
+		//     Email: "support@myapp.com",
+		//     URL:   "https://myapp.com/support",
+		// }
+
+		// Add additional servers
+		// spec.Servers = append(spec.Servers, Server{
+		//     URL:         "https://staging-api.myapp.com",
+		//     Description: "Staging Server",
+		// })
+
+		// Convert back to JSON - or use GenerateJSON() for simple cases
+		return generator.GenerateJSON()
+	}
+
+	// Use this generator function with your handlers
+	_ = generatorFunc
+}

pkg/openapi/generator.go

@@ -0,0 +1,513 @@
+package openapi
+
+import (
+	"encoding/json"
+	"fmt"
+	"reflect"
+	"strings"
+
+	"github.com/bitechdev/ResolveSpec/pkg/modelregistry"
+)
+
+// OpenAPISpec represents the OpenAPI 3.0 specification structure
+type OpenAPISpec struct {
+	OpenAPI    string                `json:"openapi"`
+	Info       Info                  `json:"info"`
+	Servers    []Server              `json:"servers,omitempty"`
+	Paths      map[string]PathItem   `json:"paths"`
+	Components Components            `json:"components"`
+	Security   []map[string][]string `json:"security,omitempty"`
+}
+
+type Info struct {
+	Title       string   `json:"title"`
+	Description string   `json:"description,omitempty"`
+	Version     string   `json:"version"`
+	Contact     *Contact `json:"contact,omitempty"`
+}
+
+type Contact struct {
+	Name  string `json:"name,omitempty"`
+	URL   string `json:"url,omitempty"`
+	Email string `json:"email,omitempty"`
+}
+
+type Server struct {
+	URL         string `json:"url"`
+	Description string `json:"description,omitempty"`
+}
+
+type PathItem struct {
+	Get     *Operation `json:"get,omitempty"`
+	Post    *Operation `json:"post,omitempty"`
+	Put     *Operation `json:"put,omitempty"`
+	Patch   *Operation `json:"patch,omitempty"`
+	Delete  *Operation `json:"delete,omitempty"`
+	Options *Operation `json:"options,omitempty"`
+}
+
+type Operation struct {
+	Summary     string                `json:"summary,omitempty"`
+	Description string                `json:"description,omitempty"`
+	OperationID string                `json:"operationId,omitempty"`
+	Tags        []string              `json:"tags,omitempty"`
+	Parameters  []Parameter           `json:"parameters,omitempty"`
+	RequestBody *RequestBody          `json:"requestBody,omitempty"`
+	Responses   map[string]Response   `json:"responses"`
+	Security    []map[string][]string `json:"security,omitempty"`
+}
+
+type Parameter struct {
+	Name        string      `json:"name"`
+	In          string      `json:"in"` // "query", "header", "path", "cookie"
+	Description string      `json:"description,omitempty"`
+	Required    bool        `json:"required,omitempty"`
+	Schema      *Schema     `json:"schema,omitempty"`
+	Example     interface{} `json:"example,omitempty"`
+}
+
+type RequestBody struct {
+	Description string               `json:"description,omitempty"`
+	Required    bool                 `json:"required,omitempty"`
+	Content     map[string]MediaType `json:"content"`
+}
+
+type MediaType struct {
+	Schema  *Schema     `json:"schema,omitempty"`
+	Example interface{} `json:"example,omitempty"`
+}
+
+type Response struct {
+	Description string               `json:"description"`
+	Content     map[string]MediaType `json:"content,omitempty"`
+}
+
+type Components struct {
+	Schemas         map[string]Schema         `json:"schemas,omitempty"`
+	SecuritySchemes map[string]SecurityScheme `json:"securitySchemes,omitempty"`
+}
+
+type Schema struct {
+	Type                 string             `json:"type,omitempty"`
+	Format               string             `json:"format,omitempty"`
+	Description          string             `json:"description,omitempty"`
+	Properties           map[string]*Schema `json:"properties,omitempty"`
+	Items                *Schema            `json:"items,omitempty"`
+	Required             []string           `json:"required,omitempty"`
+	Ref                  string             `json:"$ref,omitempty"`
+	Enum                 []interface{}      `json:"enum,omitempty"`
+	Example              interface{}        `json:"example,omitempty"`
+	AdditionalProperties interface{}        `json:"additionalProperties,omitempty"`
+	OneOf                []*Schema          `json:"oneOf,omitempty"`
+	AnyOf                []*Schema          `json:"anyOf,omitempty"`
+}
+
+type SecurityScheme struct {
+	Type         string `json:"type"` // "apiKey", "http", "oauth2", "openIdConnect"
+	Description  string `json:"description,omitempty"`
+	Name         string `json:"name,omitempty"`         // For apiKey
+	In           string `json:"in,omitempty"`           // For apiKey: "query", "header", "cookie"
+	Scheme       string `json:"scheme,omitempty"`       // For http: "basic", "bearer"
+	BearerFormat string `json:"bearerFormat,omitempty"` // For http bearer
+}
+
+// GeneratorConfig holds configuration for OpenAPI spec generation
+type GeneratorConfig struct {
+	Title               string
+	Description         string
+	Version             string
+	BaseURL             string
+	Registry            *modelregistry.DefaultModelRegistry
+	IncludeRestheadSpec bool
+	IncludeResolveSpec  bool
+	IncludeFuncSpec     bool
+	FuncSpecEndpoints   map[string]FuncSpecEndpoint // path -> endpoint info
+}
+
+// FuncSpecEndpoint represents a FuncSpec endpoint for OpenAPI generation
+type FuncSpecEndpoint struct {
+	Path        string
+	Method      string
+	Summary     string
+	Description string
+	SQLQuery    string
+	Parameters  []string // Parameter names extracted from SQL
+}
+
+// Generator creates OpenAPI specifications
+type Generator struct {
+	config GeneratorConfig
+}
+
+// NewGenerator creates a new OpenAPI generator
+func NewGenerator(config GeneratorConfig) *Generator {
+	if config.Title == "" {
+		config.Title = "ResolveSpec API"
+	}
+	if config.Version == "" {
+		config.Version = "1.0.0"
+	}
+	return &Generator{config: config}
+}
+
+// Generate creates the complete OpenAPI specification
+func (g *Generator) Generate() (*OpenAPISpec, error) {
+	spec := &OpenAPISpec{
+		OpenAPI: "3.0.0",
+		Info: Info{
+			Title:       g.config.Title,
+			Description: g.config.Description,
+			Version:     g.config.Version,
+		},
+		Paths: make(map[string]PathItem),
+		Components: Components{
+			Schemas:         make(map[string]Schema),
+			SecuritySchemes: g.generateSecuritySchemes(),
+		},
+	}
+
+	if g.config.BaseURL != "" {
+		spec.Servers = []Server{
+			{URL: g.config.BaseURL, Description: "API Server"},
+		}
+	}
+
+	// Add common schemas
+	g.addCommonSchemas(spec)
+
+	// Generate paths and schemas from registered models
+	if err := g.generateFromModels(spec); err != nil {
+		return nil, err
+	}
+
+	return spec, nil
+}
+
+// GenerateJSON generates OpenAPI spec as JSON string
+func (g *Generator) GenerateJSON() (string, error) {
+	spec, err := g.Generate()
+	if err != nil {
+		return "", err
+	}
+
+	data, err := json.MarshalIndent(spec, "", "  ")
+	if err != nil {
+		return "", fmt.Errorf("failed to marshal spec: %w", err)
+	}
+
+	return string(data), nil
+}
+
+// generateSecuritySchemes creates security scheme definitions
+func (g *Generator) generateSecuritySchemes() map[string]SecurityScheme {
+	return map[string]SecurityScheme{
+		"BearerAuth": {
+			Type:         "http",
+			Scheme:       "bearer",
+			BearerFormat: "JWT",
+			Description:  "JWT Bearer token authentication",
+		},
+		"SessionToken": {
+			Type:        "apiKey",
+			In:          "header",
+			Name:        "Authorization",
+			Description: "Session token authentication",
+		},
+		"CookieAuth": {
+			Type:        "apiKey",
+			In:          "cookie",
+			Name:        "session_token",
+			Description: "Cookie-based session authentication",
+		},
+		"HeaderAuth": {
+			Type:        "apiKey",
+			In:          "header",
+			Name:        "X-User-ID",
+			Description: "Header-based user authentication",
+		},
+	}
+}
+
+// addCommonSchemas adds common reusable schemas
+func (g *Generator) addCommonSchemas(spec *OpenAPISpec) {
+	// Response wrapper schema
+	spec.Components.Schemas["Response"] = Schema{
+		Type: "object",
+		Properties: map[string]*Schema{
+			"success":  {Type: "boolean", Description: "Indicates if the operation was successful"},
+			"data":     {Description: "The response data"},
+			"metadata": {Ref: "#/components/schemas/Metadata"},
+			"error":    {Ref: "#/components/schemas/APIError"},
+		},
+	}
+
+	// Metadata schema
+	spec.Components.Schemas["Metadata"] = Schema{
+		Type: "object",
+		Properties: map[string]*Schema{
+			"total":     {Type: "integer", Description: "Total number of records"},
+			"count":     {Type: "integer", Description: "Number of records in this response"},
+			"filtered":  {Type: "integer", Description: "Number of records after filtering"},
+			"limit":     {Type: "integer", Description: "Limit applied"},
+			"offset":    {Type: "integer", Description: "Offset applied"},
+			"rowNumber": {Type: "integer", Description: "Row number for cursor pagination"},
+		},
+	}
+
+	// APIError schema
+	spec.Components.Schemas["APIError"] = Schema{
+		Type: "object",
+		Properties: map[string]*Schema{
+			"code":    {Type: "string", Description: "Error code"},
+			"message": {Type: "string", Description: "Error message"},
+			"details": {Type: "string", Description: "Detailed error information"},
+		},
+	}
+
+	// RequestOptions schema
+	spec.Components.Schemas["RequestOptions"] = Schema{
+		Type: "object",
+		Properties: map[string]*Schema{
+			"preload": {
+				Type:        "array",
+				Description: "Relations to eager load",
+				Items:       &Schema{Ref: "#/components/schemas/PreloadOption"},
+			},
+			"columns": {
+				Type:        "array",
+				Description: "Columns to select",
+				Items:       &Schema{Type: "string"},
+			},
+			"omitColumns": {
+				Type:        "array",
+				Description: "Columns to exclude",
+				Items:       &Schema{Type: "string"},
+			},
+			"filters": {
+				Type:        "array",
+				Description: "Filter conditions",
+				Items:       &Schema{Ref: "#/components/schemas/FilterOption"},
+			},
+			"sort": {
+				Type:        "array",
+				Description: "Sort specifications",
+				Items:       &Schema{Ref: "#/components/schemas/SortOption"},
+			},
+			"limit":  {Type: "integer", Description: "Maximum number of records"},
+			"offset": {Type: "integer", Description: "Number of records to skip"},
+		},
+	}
+
+	// FilterOption schema
+	spec.Components.Schemas["FilterOption"] = Schema{
+		Type: "object",
+		Properties: map[string]*Schema{
+			"column":        {Type: "string", Description: "Column name"},
+			"operator":      {Type: "string", Description: "Comparison operator", Enum: []interface{}{"eq", "neq", "gt", "lt", "gte", "lte", "like", "ilike", "in", "not_in", "between", "is_null", "is_not_null"}},
+			"value":         {Description: "Filter value"},
+			"logicOperator": {Type: "string", Description: "Logic operator", Enum: []interface{}{"AND", "OR"}},
+		},
+	}
+
+	// SortOption schema
+	spec.Components.Schemas["SortOption"] = Schema{
+		Type: "object",
+		Properties: map[string]*Schema{
+			"column":    {Type: "string", Description: "Column name"},
+			"direction": {Type: "string", Description: "Sort direction", Enum: []interface{}{"asc", "desc"}},
+		},
+	}
+
+	// PreloadOption schema
+	spec.Components.Schemas["PreloadOption"] = Schema{
+		Type: "object",
+		Properties: map[string]*Schema{
+			"relation": {Type: "string", Description: "Relation name"},
+			"columns": {
+				Type:        "array",
+				Description: "Columns to select from related table",
+				Items:       &Schema{Type: "string"},
+			},
+		},
+	}
+
+	// ResolveSpec RequestBody schema
+	spec.Components.Schemas["ResolveSpecRequest"] = Schema{
+		Type: "object",
+		Properties: map[string]*Schema{
+			"operation": {Type: "string", Description: "Operation type", Enum: []interface{}{"read", "create", "update", "delete", "meta"}},
+			"data":      {Description: "Payload data (object or array)"},
+			"id":        {Type: "integer", Description: "Record ID for single operations"},
+			"options":   {Ref: "#/components/schemas/RequestOptions"},
+		},
+	}
+}
+
+// generateFromModels generates paths and schemas from registered models
+func (g *Generator) generateFromModels(spec *OpenAPISpec) error {
+	if g.config.Registry == nil {
+		return fmt.Errorf("model registry is required")
+	}
+
+	models := g.config.Registry.GetAllModels()
+
+	for name, model := range models {
+		// Parse schema.entity from model name
+		schema, entity := parseModelName(name)
+
+		// Generate schema for this model
+		modelSchema := g.generateModelSchema(model)
+		schemaName := formatSchemaName(schema, entity)
+		spec.Components.Schemas[schemaName] = modelSchema
+
+		// Generate paths for different frameworks
+		if g.config.IncludeRestheadSpec {
+			g.generateRestheadSpecPaths(spec, schema, entity, schemaName)
+		}
+
+		if g.config.IncludeResolveSpec {
+			g.generateResolveSpecPaths(spec, schema, entity, schemaName)
+		}
+	}
+
+	// Generate FuncSpec paths if configured
+	if g.config.IncludeFuncSpec && len(g.config.FuncSpecEndpoints) > 0 {
+		g.generateFuncSpecPaths(spec)
+	}
+
+	return nil
+}
+
+// generateModelSchema creates an OpenAPI schema from a Go struct
+func (g *Generator) generateModelSchema(model interface{}) Schema {
+	schema := Schema{
+		Type:       "object",
+		Properties: make(map[string]*Schema),
+		Required:   []string{},
+	}
+
+	modelType := reflect.TypeOf(model)
+	if modelType.Kind() == reflect.Ptr {
+		modelType = modelType.Elem()
+	}
+	if modelType.Kind() != reflect.Struct {
+		return schema
+	}
+
+	for i := 0; i < modelType.NumField(); i++ {
+		field := modelType.Field(i)
+
+		// Skip unexported fields
+		if !field.IsExported() {
+			continue
+		}
+
+		// Get JSON tag name
+		jsonTag := field.Tag.Get("json")
+		if jsonTag == "-" {
+			continue
+		}
+
+		fieldName := strings.Split(jsonTag, ",")[0]
+		if fieldName == "" {
+			fieldName = field.Name
+		}
+
+		// Generate property schema
+		propSchema := g.generatePropertySchema(field)
+		schema.Properties[fieldName] = propSchema
+
+		// Check if field is required (not a pointer and no omitempty)
+		if field.Type.Kind() != reflect.Ptr && !strings.Contains(jsonTag, "omitempty") {
+			schema.Required = append(schema.Required, fieldName)
+		}
+	}
+
+	return schema
+}
+
+// generatePropertySchema creates a schema for a struct field
+func (g *Generator) generatePropertySchema(field reflect.StructField) *Schema {
+	schema := &Schema{}
+
+	fieldType := field.Type
+	if fieldType.Kind() == reflect.Ptr {
+		fieldType = fieldType.Elem()
+	}
+
+	// Get description from tag
+	if desc := field.Tag.Get("description"); desc != "" {
+		schema.Description = desc
+	}
+
+	switch fieldType.Kind() {
+	case reflect.String:
+		schema.Type = "string"
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		schema.Type = "integer"
+	case reflect.Float32, reflect.Float64:
+		schema.Type = "number"
+	case reflect.Bool:
+		schema.Type = "boolean"
+	case reflect.Slice, reflect.Array:
+		schema.Type = "array"
+		elemType := fieldType.Elem()
+		if elemType.Kind() == reflect.Ptr {
+			elemType = elemType.Elem()
+		}
+		if elemType.Kind() == reflect.Struct {
+			// Complex type - would need recursive handling
+			schema.Items = &Schema{Type: "object"}
+		} else {
+			schema.Items = g.generatePropertySchema(reflect.StructField{Type: elemType})
+		}
+	case reflect.Struct:
+		// Check for time.Time
+		if fieldType.String() == "time.Time" {
+			schema.Type = "string"
+			schema.Format = "date-time"
+		} else {
+			schema.Type = "object"
+		}
+	default:
+		schema.Type = "string"
+	}
+
+	// Check for custom format from gorm/bun tags
+	if gormTag := field.Tag.Get("gorm"); gormTag != "" {
+		if strings.Contains(gormTag, "type:uuid") {
+			schema.Format = "uuid"
+		}
+	}
+
+	return schema
+}
+
+// parseModelName splits "schema.entity" or returns "public" and entity
+func parseModelName(name string) (schema, entity string) {
+	parts := strings.Split(name, ".")
+	if len(parts) == 2 {
+		return parts[0], parts[1]
+	}
+	return "public", name
+}
+
+// formatSchemaName creates a component schema name
+func formatSchemaName(schema, entity string) string {
+	if schema == "public" {
+		return toTitleCase(entity)
+	}
+	return toTitleCase(schema) + toTitleCase(entity)
+}
+
+// toTitleCase converts a string to title case (first letter uppercase)
+func toTitleCase(s string) string {
+	if s == "" {
+		return ""
+	}
+	if len(s) == 1 {
+		return strings.ToUpper(s)
+	}
+	return strings.ToUpper(s[:1]) + s[1:]
+}

pkg/openapi/generator_test.go

@@ -0,0 +1,714 @@
+package openapi
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/bitechdev/ResolveSpec/pkg/modelregistry"
+)
+
+// Test models
+type TestUser struct {
+	ID        int       `json:"id" gorm:"primaryKey" description:"User ID"`
+	Name      string    `json:"name" gorm:"not null" description:"User's full name"`
+	Email     string    `json:"email" gorm:"unique" description:"Email address"`
+	Age       int       `json:"age" description:"User age"`
+	IsActive  bool      `json:"is_active" description:"Active status"`
+	CreatedAt time.Time `json:"created_at" description:"Creation timestamp"`
+	UpdatedAt *time.Time `json:"updated_at,omitempty" description:"Last update timestamp"`
+	Roles     []string  `json:"roles,omitempty" description:"User roles"`
+}
+
+type TestProduct struct {
+	ID          int     `json:"id" gorm:"primaryKey"`
+	Name        string  `json:"name" gorm:"not null"`
+	Description string  `json:"description"`
+	Price       float64 `json:"price"`
+	InStock     bool    `json:"in_stock"`
+}
+
+type TestOrder struct {
+	ID         int    `json:"id" gorm:"primaryKey"`
+	UserID     int    `json:"user_id" gorm:"not null"`
+	ProductID  int    `json:"product_id" gorm:"not null"`
+	Quantity   int    `json:"quantity"`
+	TotalPrice float64 `json:"total_price"`
+}
+
+func TestNewGenerator(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+
+	tests := []struct {
+		name   string
+		config GeneratorConfig
+		want   string // expected title
+	}{
+		{
+			name: "with all fields",
+			config: GeneratorConfig{
+				Title:       "Test API",
+				Description: "Test Description",
+				Version:     "1.0.0",
+				BaseURL:     "http://localhost:8080",
+				Registry:    registry,
+			},
+			want: "Test API",
+		},
+		{
+			name: "with defaults",
+			config: GeneratorConfig{
+				Registry: registry,
+			},
+			want: "ResolveSpec API",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gen := NewGenerator(tt.config)
+			if gen == nil {
+				t.Fatal("NewGenerator returned nil")
+			}
+			if gen.config.Title != tt.want {
+				t.Errorf("Title = %v, want %v", gen.config.Title, tt.want)
+			}
+		})
+	}
+}
+
+func TestGenerateBasicSpec(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+	err := registry.RegisterModel("public.users", TestUser{})
+	if err != nil {
+		t.Fatalf("Failed to register model: %v", err)
+	}
+
+	config := GeneratorConfig{
+		Title:               "Test API",
+		Version:             "1.0.0",
+		Registry:            registry,
+		IncludeRestheadSpec: true,
+	}
+
+	gen := NewGenerator(config)
+	spec, err := gen.Generate()
+	if err != nil {
+		t.Fatalf("Generate failed: %v", err)
+	}
+
+	// Test basic spec structure
+	if spec.OpenAPI != "3.0.0" {
+		t.Errorf("OpenAPI version = %v, want 3.0.0", spec.OpenAPI)
+	}
+	if spec.Info.Title != "Test API" {
+		t.Errorf("Title = %v, want Test API", spec.Info.Title)
+	}
+	if spec.Info.Version != "1.0.0" {
+		t.Errorf("Version = %v, want 1.0.0", spec.Info.Version)
+	}
+
+	// Test that common schemas are added
+	if spec.Components.Schemas["Response"].Type != "object" {
+		t.Error("Response schema not found or invalid")
+	}
+	if spec.Components.Schemas["Metadata"].Type != "object" {
+		t.Error("Metadata schema not found or invalid")
+	}
+
+	// Test that model schema is added
+	if _, exists := spec.Components.Schemas["Users"]; !exists {
+		t.Error("Users schema not found")
+	}
+
+	// Test that security schemes are added
+	if len(spec.Components.SecuritySchemes) == 0 {
+		t.Error("Security schemes not added")
+	}
+}
+
+func TestGenerateModelSchema(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+	gen := NewGenerator(GeneratorConfig{Registry: registry})
+
+	schema := gen.generateModelSchema(TestUser{})
+
+	// Test basic properties
+	if schema.Type != "object" {
+		t.Errorf("Schema type = %v, want object", schema.Type)
+	}
+
+	// Test that properties are generated
+	expectedProps := []string{"id", "name", "email", "age", "is_active", "created_at", "updated_at", "roles"}
+	for _, prop := range expectedProps {
+		if _, exists := schema.Properties[prop]; !exists {
+			t.Errorf("Property %s not found in schema", prop)
+		}
+	}
+
+	// Test property types
+	if schema.Properties["id"].Type != "integer" {
+		t.Errorf("id type = %v, want integer", schema.Properties["id"].Type)
+	}
+	if schema.Properties["name"].Type != "string" {
+		t.Errorf("name type = %v, want string", schema.Properties["name"].Type)
+	}
+	if schema.Properties["is_active"].Type != "boolean" {
+		t.Errorf("is_active type = %v, want boolean", schema.Properties["is_active"].Type)
+	}
+
+	// Test array type
+	if schema.Properties["roles"].Type != "array" {
+		t.Errorf("roles type = %v, want array", schema.Properties["roles"].Type)
+	}
+	if schema.Properties["roles"].Items.Type != "string" {
+		t.Errorf("roles items type = %v, want string", schema.Properties["roles"].Items.Type)
+	}
+
+	// Test time.Time format
+	if schema.Properties["created_at"].Type != "string" {
+		t.Errorf("created_at type = %v, want string", schema.Properties["created_at"].Type)
+	}
+	if schema.Properties["created_at"].Format != "date-time" {
+		t.Errorf("created_at format = %v, want date-time", schema.Properties["created_at"].Format)
+	}
+
+	// Test required fields (non-pointer, no omitempty)
+	requiredFields := map[string]bool{}
+	for _, field := range schema.Required {
+		requiredFields[field] = true
+	}
+	if !requiredFields["id"] {
+		t.Error("id should be required")
+	}
+	if !requiredFields["name"] {
+		t.Error("name should be required")
+	}
+	if requiredFields["updated_at"] {
+		t.Error("updated_at should not be required (pointer + omitempty)")
+	}
+	if requiredFields["roles"] {
+		t.Error("roles should not be required (omitempty)")
+	}
+
+	// Test descriptions
+	if schema.Properties["id"].Description != "User ID" {
+		t.Errorf("id description = %v, want 'User ID'", schema.Properties["id"].Description)
+	}
+}
+
+func TestGenerateRestheadSpecPaths(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+	err := registry.RegisterModel("public.users", TestUser{})
+	if err != nil {
+		t.Fatalf("Failed to register model: %v", err)
+	}
+
+	config := GeneratorConfig{
+		Title:               "Test API",
+		Version:             "1.0.0",
+		Registry:            registry,
+		IncludeRestheadSpec: true,
+	}
+
+	gen := NewGenerator(config)
+	spec, err := gen.Generate()
+	if err != nil {
+		t.Fatalf("Generate failed: %v", err)
+	}
+
+	// Test that paths are generated
+	expectedPaths := []string{
+		"/public/users",
+		"/public/users/{id}",
+		"/public/users/metadata",
+	}
+
+	for _, path := range expectedPaths {
+		if _, exists := spec.Paths[path]; !exists {
+			t.Errorf("Path %s not found", path)
+		}
+	}
+
+	// Test collection endpoint methods
+	usersPath := spec.Paths["/public/users"]
+	if usersPath.Get == nil {
+		t.Error("GET method not found for /public/users")
+	}
+	if usersPath.Post == nil {
+		t.Error("POST method not found for /public/users")
+	}
+	if usersPath.Options == nil {
+		t.Error("OPTIONS method not found for /public/users")
+	}
+
+	// Test single record endpoint methods
+	userIDPath := spec.Paths["/public/users/{id}"]
+	if userIDPath.Get == nil {
+		t.Error("GET method not found for /public/users/{id}")
+	}
+	if userIDPath.Put == nil {
+		t.Error("PUT method not found for /public/users/{id}")
+	}
+	if userIDPath.Patch == nil {
+		t.Error("PATCH method not found for /public/users/{id}")
+	}
+	if userIDPath.Delete == nil {
+		t.Error("DELETE method not found for /public/users/{id}")
+	}
+
+	// Test metadata endpoint
+	metadataPath := spec.Paths["/public/users/metadata"]
+	if metadataPath.Get == nil {
+		t.Error("GET method not found for /public/users/metadata")
+	}
+
+	// Test operation details
+	getOp := usersPath.Get
+	if getOp.Summary == "" {
+		t.Error("GET operation summary is empty")
+	}
+	if getOp.OperationID == "" {
+		t.Error("GET operation ID is empty")
+	}
+	if len(getOp.Tags) == 0 {
+		t.Error("GET operation has no tags")
+	}
+	if len(getOp.Parameters) == 0 {
+		t.Error("GET operation has no parameters")
+	}
+
+	// Test RestheadSpec headers
+	hasFiltersHeader := false
+	for _, param := range getOp.Parameters {
+		if param.Name == "X-Filters" && param.In == "header" {
+			hasFiltersHeader = true
+			break
+		}
+	}
+	if !hasFiltersHeader {
+		t.Error("X-Filters header parameter not found")
+	}
+}
+
+func TestGenerateResolveSpecPaths(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+	err := registry.RegisterModel("public.products", TestProduct{})
+	if err != nil {
+		t.Fatalf("Failed to register model: %v", err)
+	}
+
+	config := GeneratorConfig{
+		Title:              "Test API",
+		Version:            "1.0.0",
+		Registry:           registry,
+		IncludeResolveSpec: true,
+	}
+
+	gen := NewGenerator(config)
+	spec, err := gen.Generate()
+	if err != nil {
+		t.Fatalf("Generate failed: %v", err)
+	}
+
+	// Test that paths are generated
+	expectedPaths := []string{
+		"/resolve/public/products",
+		"/resolve/public/products/{id}",
+	}
+
+	for _, path := range expectedPaths {
+		if _, exists := spec.Paths[path]; !exists {
+			t.Errorf("Path %s not found", path)
+		}
+	}
+
+	// Test collection endpoint methods
+	productsPath := spec.Paths["/resolve/public/products"]
+	if productsPath.Post == nil {
+		t.Error("POST method not found for /resolve/public/products")
+	}
+	if productsPath.Get == nil {
+		t.Error("GET method not found for /resolve/public/products")
+	}
+	if productsPath.Options == nil {
+		t.Error("OPTIONS method not found for /resolve/public/products")
+	}
+
+	// Test POST operation has request body
+	postOp := productsPath.Post
+	if postOp.RequestBody == nil {
+		t.Error("POST operation has no request body")
+	}
+	if _, exists := postOp.RequestBody.Content["application/json"]; !exists {
+		t.Error("POST operation request body has no application/json content")
+	}
+
+	// Test request body schema references ResolveSpecRequest
+	reqBodySchema := postOp.RequestBody.Content["application/json"].Schema
+	if reqBodySchema.Ref != "#/components/schemas/ResolveSpecRequest" {
+		t.Errorf("Request body schema ref = %v, want #/components/schemas/ResolveSpecRequest", reqBodySchema.Ref)
+	}
+}
+
+func TestGenerateFuncSpecPaths(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+
+	funcSpecEndpoints := map[string]FuncSpecEndpoint{
+		"/api/reports/sales": {
+			Path:        "/api/reports/sales",
+			Method:      "GET",
+			Summary:     "Get sales report",
+			Description: "Returns sales data",
+			Parameters:  []string{"start_date", "end_date"},
+		},
+		"/api/analytics/users": {
+			Path:        "/api/analytics/users",
+			Method:      "POST",
+			Summary:     "Get user analytics",
+			Description: "Returns user activity",
+			Parameters:  []string{"user_id"},
+		},
+	}
+
+	config := GeneratorConfig{
+		Title:             "Test API",
+		Version:           "1.0.0",
+		Registry:          registry,
+		IncludeFuncSpec:   true,
+		FuncSpecEndpoints: funcSpecEndpoints,
+	}
+
+	gen := NewGenerator(config)
+	spec, err := gen.Generate()
+	if err != nil {
+		t.Fatalf("Generate failed: %v", err)
+	}
+
+	// Test that FuncSpec paths are generated
+	salesPath := spec.Paths["/api/reports/sales"]
+	if salesPath.Get == nil {
+		t.Error("GET method not found for /api/reports/sales")
+	}
+	if salesPath.Get.Summary != "Get sales report" {
+		t.Errorf("GET summary = %v, want 'Get sales report'", salesPath.Get.Summary)
+	}
+	if len(salesPath.Get.Parameters) != 2 {
+		t.Errorf("GET has %d parameters, want 2", len(salesPath.Get.Parameters))
+	}
+
+	analyticsPath := spec.Paths["/api/analytics/users"]
+	if analyticsPath.Post == nil {
+		t.Error("POST method not found for /api/analytics/users")
+	}
+	if len(analyticsPath.Post.Parameters) != 1 {
+		t.Errorf("POST has %d parameters, want 1", len(analyticsPath.Post.Parameters))
+	}
+}
+
+func TestGenerateJSON(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+	err := registry.RegisterModel("public.users", TestUser{})
+	if err != nil {
+		t.Fatalf("Failed to register model: %v", err)
+	}
+
+	config := GeneratorConfig{
+		Title:               "Test API",
+		Version:             "1.0.0",
+		Registry:            registry,
+		IncludeRestheadSpec: true,
+	}
+
+	gen := NewGenerator(config)
+	jsonStr, err := gen.GenerateJSON()
+	if err != nil {
+		t.Fatalf("GenerateJSON failed: %v", err)
+	}
+
+	// Test that it's valid JSON
+	var spec OpenAPISpec
+	if err := json.Unmarshal([]byte(jsonStr), &spec); err != nil {
+		t.Fatalf("Generated JSON is invalid: %v", err)
+	}
+
+	// Test basic structure
+	if spec.OpenAPI != "3.0.0" {
+		t.Errorf("OpenAPI version = %v, want 3.0.0", spec.OpenAPI)
+	}
+	if spec.Info.Title != "Test API" {
+		t.Errorf("Title = %v, want Test API", spec.Info.Title)
+	}
+
+	// Test that JSON contains expected fields
+	if !strings.Contains(jsonStr, `"openapi"`) {
+		t.Error("JSON doesn't contain 'openapi' field")
+	}
+	if !strings.Contains(jsonStr, `"paths"`) {
+		t.Error("JSON doesn't contain 'paths' field")
+	}
+	if !strings.Contains(jsonStr, `"components"`) {
+		t.Error("JSON doesn't contain 'components' field")
+	}
+}
+
+func TestMultipleModels(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+	registry.RegisterModel("public.users", TestUser{})
+	registry.RegisterModel("public.products", TestProduct{})
+	registry.RegisterModel("public.orders", TestOrder{})
+
+	config := GeneratorConfig{
+		Title:               "Test API",
+		Version:             "1.0.0",
+		Registry:            registry,
+		IncludeRestheadSpec: true,
+	}
+
+	gen := NewGenerator(config)
+	spec, err := gen.Generate()
+	if err != nil {
+		t.Fatalf("Generate failed: %v", err)
+	}
+
+	// Test that all model schemas are generated
+	expectedSchemas := []string{"Users", "Products", "Orders"}
+	for _, schemaName := range expectedSchemas {
+		if _, exists := spec.Components.Schemas[schemaName]; !exists {
+			t.Errorf("Schema %s not found", schemaName)
+		}
+	}
+
+	// Test that all paths are generated
+	expectedPaths := []string{
+		"/public/users",
+		"/public/products",
+		"/public/orders",
+	}
+	for _, path := range expectedPaths {
+		if _, exists := spec.Paths[path]; !exists {
+			t.Errorf("Path %s not found", path)
+		}
+	}
+}
+
+func TestModelNameParsing(t *testing.T) {
+	tests := []struct {
+		name         string
+		fullName     string
+		wantSchema   string
+		wantEntity   string
+	}{
+		{
+			name:       "with schema",
+			fullName:   "public.users",
+			wantSchema: "public",
+			wantEntity: "users",
+		},
+		{
+			name:       "without schema",
+			fullName:   "users",
+			wantSchema: "public",
+			wantEntity: "users",
+		},
+		{
+			name:       "custom schema",
+			fullName:   "custom.products",
+			wantSchema: "custom",
+			wantEntity: "products",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			schema, entity := parseModelName(tt.fullName)
+			if schema != tt.wantSchema {
+				t.Errorf("schema = %v, want %v", schema, tt.wantSchema)
+			}
+			if entity != tt.wantEntity {
+				t.Errorf("entity = %v, want %v", entity, tt.wantEntity)
+			}
+		})
+	}
+}
+
+func TestSchemaNameFormatting(t *testing.T) {
+	tests := []struct {
+		name       string
+		schema     string
+		entity     string
+		wantName   string
+	}{
+		{
+			name:     "public schema",
+			schema:   "public",
+			entity:   "users",
+			wantName: "Users",
+		},
+		{
+			name:     "custom schema",
+			schema:   "custom",
+			entity:   "products",
+			wantName: "CustomProducts",
+		},
+		{
+			name:     "multi-word entity",
+			schema:   "public",
+			entity:   "user_profiles",
+			wantName: "User_profiles",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			name := formatSchemaName(tt.schema, tt.entity)
+			if name != tt.wantName {
+				t.Errorf("formatSchemaName() = %v, want %v", name, tt.wantName)
+			}
+		})
+	}
+}
+
+func TestToTitleCase(t *testing.T) {
+	tests := []struct {
+		input string
+		want  string
+	}{
+		{"users", "Users"},
+		{"products", "Products"},
+		{"userProfiles", "UserProfiles"},
+		{"a", "A"},
+		{"", ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			got := toTitleCase(tt.input)
+			if got != tt.want {
+				t.Errorf("toTitleCase(%v) = %v, want %v", tt.input, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestGenerateWithBaseURL(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+	registry.RegisterModel("public.users", TestUser{})
+
+	config := GeneratorConfig{
+		Title:               "Test API",
+		Version:             "1.0.0",
+		BaseURL:             "https://api.example.com",
+		Registry:            registry,
+		IncludeRestheadSpec: true,
+	}
+
+	gen := NewGenerator(config)
+	spec, err := gen.Generate()
+	if err != nil {
+		t.Fatalf("Generate failed: %v", err)
+	}
+
+	// Test that server is added
+	if len(spec.Servers) == 0 {
+		t.Fatal("No servers added")
+	}
+	if spec.Servers[0].URL != "https://api.example.com" {
+		t.Errorf("Server URL = %v, want https://api.example.com", spec.Servers[0].URL)
+	}
+	if spec.Servers[0].Description != "API Server" {
+		t.Errorf("Server description = %v, want 'API Server'", spec.Servers[0].Description)
+	}
+}
+
+func TestGenerateCombinedFrameworks(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+	registry.RegisterModel("public.users", TestUser{})
+
+	config := GeneratorConfig{
+		Title:               "Test API",
+		Version:             "1.0.0",
+		Registry:            registry,
+		IncludeRestheadSpec: true,
+		IncludeResolveSpec:  true,
+	}
+
+	gen := NewGenerator(config)
+	spec, err := gen.Generate()
+	if err != nil {
+		t.Fatalf("Generate failed: %v", err)
+	}
+
+	// Test that both RestheadSpec and ResolveSpec paths are generated
+	restheadPath := "/public/users"
+	resolveSpecPath := "/resolve/public/users"
+
+	if _, exists := spec.Paths[restheadPath]; !exists {
+		t.Errorf("RestheadSpec path %s not found", restheadPath)
+	}
+	if _, exists := spec.Paths[resolveSpecPath]; !exists {
+		t.Errorf("ResolveSpec path %s not found", resolveSpecPath)
+	}
+}
+
+func TestNilRegistry(t *testing.T) {
+	config := GeneratorConfig{
+		Title:   "Test API",
+		Version: "1.0.0",
+	}
+
+	gen := NewGenerator(config)
+	_, err := gen.Generate()
+	if err == nil {
+		t.Error("Expected error for nil registry, got nil")
+	}
+	if !strings.Contains(err.Error(), "registry") {
+		t.Errorf("Error message should mention registry, got: %v", err)
+	}
+}
+
+func TestSecuritySchemes(t *testing.T) {
+	registry := modelregistry.NewModelRegistry()
+	config := GeneratorConfig{
+		Registry: registry,
+	}
+
+	gen := NewGenerator(config)
+	spec, err := gen.Generate()
+	if err != nil {
+		t.Fatalf("Generate failed: %v", err)
+	}
+
+	// Test that all security schemes are present
+	expectedSchemes := []string{"BearerAuth", "SessionToken", "CookieAuth", "HeaderAuth"}
+	for _, scheme := range expectedSchemes {
+		if _, exists := spec.Components.SecuritySchemes[scheme]; !exists {
+			t.Errorf("Security scheme %s not found", scheme)
+		}
+	}
+
+	// Test BearerAuth scheme details
+	bearerAuth := spec.Components.SecuritySchemes["BearerAuth"]
+	if bearerAuth.Type != "http" {
+		t.Errorf("BearerAuth type = %v, want http", bearerAuth.Type)
+	}
+	if bearerAuth.Scheme != "bearer" {
+		t.Errorf("BearerAuth scheme = %v, want bearer", bearerAuth.Scheme)
+	}
+	if bearerAuth.BearerFormat != "JWT" {
+		t.Errorf("BearerAuth format = %v, want JWT", bearerAuth.BearerFormat)
+	}
+
+	// Test HeaderAuth scheme details
+	headerAuth := spec.Components.SecuritySchemes["HeaderAuth"]
+	if headerAuth.Type != "apiKey" {
+		t.Errorf("HeaderAuth type = %v, want apiKey", headerAuth.Type)
+	}
+	if headerAuth.In != "header" {
+		t.Errorf("HeaderAuth in = %v, want header", headerAuth.In)
+	}
+	if headerAuth.Name != "X-User-ID" {
+		t.Errorf("HeaderAuth name = %v, want X-User-ID", headerAuth.Name)
+	}
+}

pkg/openapi/paths.go

@@ -0,0 +1,499 @@
+package openapi
+
+import (
+	"fmt"
+)
+
+// generateRestheadSpecPaths generates OpenAPI paths for RestheadSpec endpoints
+func (g *Generator) generateRestheadSpecPaths(spec *OpenAPISpec, schema, entity, schemaName string) {
+	basePath := fmt.Sprintf("/%s/%s", schema, entity)
+	idPath := fmt.Sprintf("/%s/%s/{id}", schema, entity)
+	metaPath := fmt.Sprintf("/%s/%s/metadata", schema, entity)
+
+	// Collection endpoint: GET (list), POST (create)
+	spec.Paths[basePath] = PathItem{
+		Get: &Operation{
+			Summary:     fmt.Sprintf("List %s records", entity),
+			Description: fmt.Sprintf("Retrieve a list of %s records with optional filtering, sorting, and pagination via headers", entity),
+			OperationID: fmt.Sprintf("listRestheadSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (RestheadSpec)", entity)},
+			Parameters:  g.getRestheadSpecHeaders(),
+			Responses: map[string]Response{
+				"200": {
+					Description: "Successful response",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{
+								Type: "object",
+								Properties: map[string]*Schema{
+									"success":  {Type: "boolean"},
+									"data":     {Type: "array", Items: &Schema{Ref: fmt.Sprintf("#/components/schemas/%s", schemaName)}},
+									"metadata": {Ref: "#/components/schemas/Metadata"},
+								},
+							},
+						},
+					},
+				},
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		},
+		Post: &Operation{
+			Summary:     fmt.Sprintf("Create %s record", entity),
+			Description: fmt.Sprintf("Create a new %s record", entity),
+			OperationID: fmt.Sprintf("createRestheadSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (RestheadSpec)", entity)},
+			RequestBody: &RequestBody{
+				Required:    true,
+				Description: fmt.Sprintf("%s object to create", entity),
+				Content: map[string]MediaType{
+					"application/json": {
+						Schema: &Schema{Ref: fmt.Sprintf("#/components/schemas/%s", schemaName)},
+					},
+				},
+			},
+			Responses: map[string]Response{
+				"201": {
+					Description: "Record created successfully",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{
+								Type: "object",
+								Properties: map[string]*Schema{
+									"success": {Type: "boolean"},
+									"data":    {Ref: fmt.Sprintf("#/components/schemas/%s", schemaName)},
+								},
+							},
+						},
+					},
+				},
+				"400": g.errorResponse("Bad request"),
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		},
+		Options: &Operation{
+			Summary:     "CORS preflight",
+			Description: "Handle CORS preflight requests",
+			OperationID: fmt.Sprintf("optionsRestheadSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (RestheadSpec)", entity)},
+			Responses: map[string]Response{
+				"204": {Description: "No content"},
+			},
+		},
+	}
+
+	// Single record endpoint: GET (read), PUT/PATCH (update), DELETE
+	spec.Paths[idPath] = PathItem{
+		Get: &Operation{
+			Summary:     fmt.Sprintf("Get %s record by ID", entity),
+			Description: fmt.Sprintf("Retrieve a single %s record by its ID", entity),
+			OperationID: fmt.Sprintf("getRestheadSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (RestheadSpec)", entity)},
+			Parameters: []Parameter{
+				{Name: "id", In: "path", Required: true, Description: "Record ID", Schema: &Schema{Type: "integer"}},
+			},
+			Responses: map[string]Response{
+				"200": {
+					Description: "Successful response",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{
+								Type: "object",
+								Properties: map[string]*Schema{
+									"success": {Type: "boolean"},
+									"data":    {Ref: fmt.Sprintf("#/components/schemas/%s", schemaName)},
+								},
+							},
+						},
+					},
+				},
+				"404": g.errorResponse("Record not found"),
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		},
+		Put: &Operation{
+			Summary:     fmt.Sprintf("Update %s record", entity),
+			Description: fmt.Sprintf("Update an existing %s record by ID", entity),
+			OperationID: fmt.Sprintf("updateRestheadSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (RestheadSpec)", entity)},
+			Parameters: []Parameter{
+				{Name: "id", In: "path", Required: true, Description: "Record ID", Schema: &Schema{Type: "integer"}},
+			},
+			RequestBody: &RequestBody{
+				Required:    true,
+				Description: fmt.Sprintf("Updated %s object", entity),
+				Content: map[string]MediaType{
+					"application/json": {
+						Schema: &Schema{Ref: fmt.Sprintf("#/components/schemas/%s", schemaName)},
+					},
+				},
+			},
+			Responses: map[string]Response{
+				"200": {
+					Description: "Record updated successfully",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{
+								Type: "object",
+								Properties: map[string]*Schema{
+									"success": {Type: "boolean"},
+									"data":    {Ref: fmt.Sprintf("#/components/schemas/%s", schemaName)},
+								},
+							},
+						},
+					},
+				},
+				"400": g.errorResponse("Bad request"),
+				"404": g.errorResponse("Record not found"),
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		},
+		Patch: &Operation{
+			Summary:     fmt.Sprintf("Partially update %s record", entity),
+			Description: fmt.Sprintf("Partially update an existing %s record by ID", entity),
+			OperationID: fmt.Sprintf("patchRestheadSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (RestheadSpec)", entity)},
+			Parameters: []Parameter{
+				{Name: "id", In: "path", Required: true, Description: "Record ID", Schema: &Schema{Type: "integer"}},
+			},
+			RequestBody: &RequestBody{
+				Required:    true,
+				Description: fmt.Sprintf("Partial %s object", entity),
+				Content: map[string]MediaType{
+					"application/json": {
+						Schema: &Schema{Ref: fmt.Sprintf("#/components/schemas/%s", schemaName)},
+					},
+				},
+			},
+			Responses: map[string]Response{
+				"200": {
+					Description: "Record updated successfully",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{
+								Type: "object",
+								Properties: map[string]*Schema{
+									"success": {Type: "boolean"},
+									"data":    {Ref: fmt.Sprintf("#/components/schemas/%s", schemaName)},
+								},
+							},
+						},
+					},
+				},
+				"400": g.errorResponse("Bad request"),
+				"404": g.errorResponse("Record not found"),
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		},
+		Delete: &Operation{
+			Summary:     fmt.Sprintf("Delete %s record", entity),
+			Description: fmt.Sprintf("Delete a %s record by ID", entity),
+			OperationID: fmt.Sprintf("deleteRestheadSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (RestheadSpec)", entity)},
+			Parameters: []Parameter{
+				{Name: "id", In: "path", Required: true, Description: "Record ID", Schema: &Schema{Type: "integer"}},
+			},
+			Responses: map[string]Response{
+				"200": {
+					Description: "Record deleted successfully",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{
+								Type: "object",
+								Properties: map[string]*Schema{
+									"success": {Type: "boolean"},
+								},
+							},
+						},
+					},
+				},
+				"404": g.errorResponse("Record not found"),
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		},
+	}
+
+	// Metadata endpoint
+	spec.Paths[metaPath] = PathItem{
+		Get: &Operation{
+			Summary:     fmt.Sprintf("Get %s metadata", entity),
+			Description: fmt.Sprintf("Retrieve metadata information for %s table", entity),
+			OperationID: fmt.Sprintf("metadataRestheadSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (RestheadSpec)", entity)},
+			Responses: map[string]Response{
+				"200": {
+					Description: "Metadata retrieved successfully",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{
+								Type: "object",
+								Properties: map[string]*Schema{
+									"success": {Type: "boolean"},
+									"data": {
+										Type: "object",
+										Properties: map[string]*Schema{
+											"schema":  {Type: "string"},
+											"table":   {Type: "string"},
+											"columns": {Type: "array", Items: &Schema{Type: "object"}},
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		},
+	}
+}
+
+// generateResolveSpecPaths generates OpenAPI paths for ResolveSpec endpoints
+func (g *Generator) generateResolveSpecPaths(spec *OpenAPISpec, schema, entity, schemaName string) {
+	basePath := fmt.Sprintf("/resolve/%s/%s", schema, entity)
+	idPath := fmt.Sprintf("/resolve/%s/%s/{id}", schema, entity)
+
+	// Collection endpoint: POST (operations)
+	spec.Paths[basePath] = PathItem{
+		Post: &Operation{
+			Summary:     fmt.Sprintf("Perform operation on %s", entity),
+			Description: fmt.Sprintf("Execute read, create, or meta operations on %s records", entity),
+			OperationID: fmt.Sprintf("operateResolveSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (ResolveSpec)", entity)},
+			RequestBody: &RequestBody{
+				Required:    true,
+				Description: "Operation request with operation type and options",
+				Content: map[string]MediaType{
+					"application/json": {
+						Schema: &Schema{Ref: "#/components/schemas/ResolveSpecRequest"},
+						Example: map[string]interface{}{
+							"operation": "read",
+							"options": map[string]interface{}{
+								"limit": 10,
+								"filters": []map[string]interface{}{
+									{"column": "status", "operator": "eq", "value": "active"},
+								},
+							},
+						},
+					},
+				},
+			},
+			Responses: map[string]Response{
+				"200": {
+					Description: "Operation completed successfully",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{
+								Type: "object",
+								Properties: map[string]*Schema{
+									"success":  {Type: "boolean"},
+									"data":     {Type: "array", Items: &Schema{Ref: fmt.Sprintf("#/components/schemas/%s", schemaName)}},
+									"metadata": {Ref: "#/components/schemas/Metadata"},
+								},
+							},
+						},
+					},
+				},
+				"400": g.errorResponse("Bad request"),
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		},
+		Get: &Operation{
+			Summary:     fmt.Sprintf("Get %s metadata", entity),
+			Description: fmt.Sprintf("Retrieve metadata for %s", entity),
+			OperationID: fmt.Sprintf("metadataResolveSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (ResolveSpec)", entity)},
+			Responses: map[string]Response{
+				"200": {
+					Description: "Metadata retrieved successfully",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{Ref: "#/components/schemas/Response"},
+						},
+					},
+				},
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		},
+		Options: &Operation{
+			Summary:     "CORS preflight",
+			Description: "Handle CORS preflight requests",
+			OperationID: fmt.Sprintf("optionsResolveSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (ResolveSpec)", entity)},
+			Responses: map[string]Response{
+				"204": {Description: "No content"},
+			},
+		},
+	}
+
+	// Single record endpoint: POST (update/delete)
+	spec.Paths[idPath] = PathItem{
+		Post: &Operation{
+			Summary:     fmt.Sprintf("Update or delete %s record", entity),
+			Description: fmt.Sprintf("Execute update or delete operation on a specific %s record", entity),
+			OperationID: fmt.Sprintf("modifyResolveSpec%s%s", formatSchemaName(schema, ""), formatSchemaName("", entity)),
+			Tags:        []string{fmt.Sprintf("%s (ResolveSpec)", entity)},
+			Parameters: []Parameter{
+				{Name: "id", In: "path", Required: true, Description: "Record ID", Schema: &Schema{Type: "integer"}},
+			},
+			RequestBody: &RequestBody{
+				Required:    true,
+				Description: "Operation request (update or delete)",
+				Content: map[string]MediaType{
+					"application/json": {
+						Schema: &Schema{Ref: "#/components/schemas/ResolveSpecRequest"},
+						Example: map[string]interface{}{
+							"operation": "update",
+							"data": map[string]interface{}{
+								"status": "inactive",
+							},
+						},
+					},
+				},
+			},
+			Responses: map[string]Response{
+				"200": {
+					Description: "Operation completed successfully",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{
+								Type: "object",
+								Properties: map[string]*Schema{
+									"success": {Type: "boolean"},
+									"data":    {Ref: fmt.Sprintf("#/components/schemas/%s", schemaName)},
+								},
+							},
+						},
+					},
+				},
+				"400": g.errorResponse("Bad request"),
+				"404": g.errorResponse("Record not found"),
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		},
+	}
+}
+
+// generateFuncSpecPaths generates OpenAPI paths for FuncSpec endpoints
+func (g *Generator) generateFuncSpecPaths(spec *OpenAPISpec) {
+	for path, endpoint := range g.config.FuncSpecEndpoints {
+		operation := &Operation{
+			Summary:     endpoint.Summary,
+			Description: endpoint.Description,
+			OperationID: fmt.Sprintf("funcSpec%s", sanitizeOperationID(path)),
+			Tags:        []string{"FuncSpec"},
+			Parameters:  g.extractFuncSpecParameters(endpoint.Parameters),
+			Responses: map[string]Response{
+				"200": {
+					Description: "Query executed successfully",
+					Content: map[string]MediaType{
+						"application/json": {
+							Schema: &Schema{Ref: "#/components/schemas/Response"},
+						},
+					},
+				},
+				"400": g.errorResponse("Bad request"),
+				"401": g.errorResponse("Unauthorized"),
+				"500": g.errorResponse("Internal server error"),
+			},
+			Security: g.securityRequirements(),
+		}
+
+		pathItem := spec.Paths[path]
+		switch endpoint.Method {
+		case "GET":
+			pathItem.Get = operation
+		case "POST":
+			pathItem.Post = operation
+		case "PUT":
+			pathItem.Put = operation
+		case "DELETE":
+			pathItem.Delete = operation
+		}
+		spec.Paths[path] = pathItem
+	}
+}
+
+// getRestheadSpecHeaders returns all RestheadSpec header parameters
+func (g *Generator) getRestheadSpecHeaders() []Parameter {
+	return []Parameter{
+		{Name: "X-Filters", In: "header", Description: "JSON array of filter conditions", Schema: &Schema{Type: "string"}},
+		{Name: "X-Columns", In: "header", Description: "Comma-separated list of columns to select", Schema: &Schema{Type: "string"}},
+		{Name: "X-Sort", In: "header", Description: "JSON array of sort specifications", Schema: &Schema{Type: "string"}},
+		{Name: "X-Limit", In: "header", Description: "Maximum number of records to return", Schema: &Schema{Type: "integer"}},
+		{Name: "X-Offset", In: "header", Description: "Number of records to skip", Schema: &Schema{Type: "integer"}},
+		{Name: "X-Preload", In: "header", Description: "Relations to eager load (comma-separated)", Schema: &Schema{Type: "string"}},
+		{Name: "X-Expand", In: "header", Description: "Relations to expand with LEFT JOIN (comma-separated)", Schema: &Schema{Type: "string"}},
+		{Name: "X-Distinct", In: "header", Description: "Enable DISTINCT query (true/false)", Schema: &Schema{Type: "boolean"}},
+		{Name: "X-Response-Format", In: "header", Description: "Response format", Schema: &Schema{Type: "string", Enum: []interface{}{"detail", "simple", "syncfusion"}}},
+		{Name: "X-Clean-JSON", In: "header", Description: "Remove null/empty fields from response (true/false)", Schema: &Schema{Type: "boolean"}},
+		{Name: "X-Custom-SQL-Where", In: "header", Description: "Custom SQL WHERE clause (AND)", Schema: &Schema{Type: "string"}},
+		{Name: "X-Custom-SQL-Or", In: "header", Description: "Custom SQL WHERE clause (OR)", Schema: &Schema{Type: "string"}},
+	}
+}
+
+// extractFuncSpecParameters creates OpenAPI parameters from parameter names
+func (g *Generator) extractFuncSpecParameters(paramNames []string) []Parameter {
+	params := []Parameter{}
+	for _, name := range paramNames {
+		params = append(params, Parameter{
+			Name:        name,
+			In:          "query",
+			Description: fmt.Sprintf("Parameter: %s", name),
+			Schema:      &Schema{Type: "string"},
+		})
+	}
+	return params
+}
+
+// errorResponse creates a standard error response
+func (g *Generator) errorResponse(description string) Response {
+	return Response{
+		Description: description,
+		Content: map[string]MediaType{
+			"application/json": {
+				Schema: &Schema{Ref: "#/components/schemas/APIError"},
+			},
+		},
+	}
+}
+
+// securityRequirements returns all security options (user can use any)
+func (g *Generator) securityRequirements() []map[string][]string {
+	return []map[string][]string{
+		{"BearerAuth": {}},
+		{"SessionToken": {}},
+		{"CookieAuth": {}},
+		{"HeaderAuth": {}},
+	}
+}
+
+// sanitizeOperationID removes invalid characters from operation IDs
+func sanitizeOperationID(path string) string {
+	result := ""
+	for _, char := range path {
+		if (char >= 'a' && char <= 'z') || (char >= 'A' && char <= 'Z') || (char >= '0' && char <= '9') {
+			result += string(char)
+		}
+	}
+	return result
+}

pkg/reflection/generic_model.go

@@ -26,8 +26,7 @@ func GetModelColumnDetail(record reflect.Value) []ModelFieldDetail {
 		}
 	}()
 
-	var lst []ModelFieldDetail
-	lst = make([]ModelFieldDetail, 0)
+	lst := make([]ModelFieldDetail, 0)
 
 	if !record.IsValid() {
 		return lst

pkg/reflection/generic_model_test.go

@@ -0,0 +1,331 @@
+package reflection
+
+import (
+	"reflect"
+	"testing"
+)
+
+// Test models for GetModelColumnDetail
+type TestModelForColumnDetail struct {
+	ID          int    `gorm:"column:rid_test;primaryKey;type:bigserial;not null" json:"id"`
+	Name        string `gorm:"column:name;type:varchar(255);not null" json:"name"`
+	Email       string `gorm:"column:email;type:varchar(255);unique;nullable" json:"email"`
+	Description string `gorm:"column:description;type:text;null" json:"description"`
+	ForeignKey  int    `gorm:"foreignKey:parent_id" json:"foreign_key"`
+}
+
+type EmbeddedBase struct {
+	ID        int    `gorm:"column:rid_base;primaryKey;identity" json:"id"`
+	CreatedAt string `gorm:"column:created_at;type:timestamp" json:"created_at"`
+}
+
+type ModelWithEmbeddedForDetail struct {
+	EmbeddedBase
+	Title   string `gorm:"column:title;type:varchar(100);not null" json:"title"`
+	Content string `gorm:"column:content;type:text" json:"content"`
+}
+
+// Model with nil embedded pointer
+type ModelWithNilEmbedded struct {
+	ID           int            `gorm:"column:id;primaryKey" json:"id"`
+	*EmbeddedBase
+	Name         string         `gorm:"column:name" json:"name"`
+}
+
+func TestGetModelColumnDetail(t *testing.T) {
+	t.Run("simple struct", func(t *testing.T) {
+		model := TestModelForColumnDetail{
+			ID:          1,
+			Name:        "Test",
+			Email:       "test@example.com",
+			Description: "Test description",
+			ForeignKey:  100,
+		}
+
+		details := GetModelColumnDetail(reflect.ValueOf(model))
+
+		if len(details) != 5 {
+			t.Errorf("Expected 5 fields, got %d", len(details))
+		}
+
+		// Check ID field
+		found := false
+		for _, detail := range details {
+			if detail.Name == "ID" {
+				found = true
+				if detail.SQLName != "rid_test" {
+					t.Errorf("Expected SQLName 'rid_test', got '%s'", detail.SQLName)
+				}
+				// Note: primaryKey (without underscore) is not detected as primary_key
+				// The function looks for "identity" or "primary_key" (with underscore)
+				if detail.SQLDataType != "bigserial" {
+					t.Errorf("Expected SQLDataType 'bigserial', got '%s'", detail.SQLDataType)
+				}
+				if detail.Nullable {
+					t.Errorf("Expected Nullable false, got true")
+				}
+			}
+		}
+		if !found {
+			t.Errorf("ID field not found in details")
+		}
+	})
+
+	t.Run("struct with embedded fields", func(t *testing.T) {
+		model := ModelWithEmbeddedForDetail{
+			EmbeddedBase: EmbeddedBase{
+				ID:        1,
+				CreatedAt: "2024-01-01",
+			},
+			Title:   "Test Title",
+			Content: "Test Content",
+		}
+
+		details := GetModelColumnDetail(reflect.ValueOf(model))
+
+		// Should have 4 fields: ID, CreatedAt from embedded, Title, Content from main
+		if len(details) != 4 {
+			t.Errorf("Expected 4 fields, got %d", len(details))
+		}
+
+		// Check that embedded field is included
+		foundID := false
+		foundCreatedAt := false
+		for _, detail := range details {
+			if detail.Name == "ID" {
+				foundID = true
+				if detail.SQLKey != "primary_key" {
+					t.Errorf("Expected SQLKey 'primary_key' for embedded ID, got '%s'", detail.SQLKey)
+				}
+			}
+			if detail.Name == "CreatedAt" {
+				foundCreatedAt = true
+			}
+		}
+		if !foundID {
+			t.Errorf("Embedded ID field not found")
+		}
+		if !foundCreatedAt {
+			t.Errorf("Embedded CreatedAt field not found")
+		}
+	})
+
+	t.Run("nil embedded pointer is skipped", func(t *testing.T) {
+		model := ModelWithNilEmbedded{
+			ID:   1,
+			Name: "Test",
+			EmbeddedBase: nil, // nil embedded pointer
+		}
+
+		details := GetModelColumnDetail(reflect.ValueOf(model))
+
+		// Should have 2 fields: ID and Name (embedded is nil, so skipped)
+		if len(details) != 2 {
+			t.Errorf("Expected 2 fields (nil embedded skipped), got %d", len(details))
+		}
+	})
+
+	t.Run("pointer to struct", func(t *testing.T) {
+		model := &TestModelForColumnDetail{
+			ID:   1,
+			Name: "Test",
+		}
+
+		details := GetModelColumnDetail(reflect.ValueOf(model))
+
+		if len(details) != 5 {
+			t.Errorf("Expected 5 fields, got %d", len(details))
+		}
+	})
+
+	t.Run("invalid value", func(t *testing.T) {
+		var invalid reflect.Value
+		details := GetModelColumnDetail(invalid)
+
+		if len(details) != 0 {
+			t.Errorf("Expected 0 fields for invalid value, got %d", len(details))
+		}
+	})
+
+	t.Run("non-struct type", func(t *testing.T) {
+		details := GetModelColumnDetail(reflect.ValueOf(123))
+
+		if len(details) != 0 {
+			t.Errorf("Expected 0 fields for non-struct, got %d", len(details))
+		}
+	})
+
+	t.Run("nullable and not null detection", func(t *testing.T) {
+		model := TestModelForColumnDetail{}
+		details := GetModelColumnDetail(reflect.ValueOf(model))
+
+		for _, detail := range details {
+			switch detail.Name {
+			case "ID":
+				if detail.Nullable {
+					t.Errorf("ID should not be nullable (has 'not null')")
+				}
+			case "Name":
+				if detail.Nullable {
+					t.Errorf("Name should not be nullable (has 'not null')")
+				}
+			case "Email":
+				if !detail.Nullable {
+					t.Errorf("Email should be nullable (has 'nullable')")
+				}
+			case "Description":
+				if !detail.Nullable {
+					t.Errorf("Description should be nullable (has 'null')")
+				}
+			}
+		}
+	})
+
+	t.Run("unique and uniqueindex detection", func(t *testing.T) {
+		type UniqueTestModel struct {
+			ID       int    `gorm:"column:id;primary_key"`
+			Username string `gorm:"column:username;unique"`
+			Email    string `gorm:"column:email;uniqueindex"`
+		}
+
+		model := UniqueTestModel{}
+		details := GetModelColumnDetail(reflect.ValueOf(model))
+
+		for _, detail := range details {
+			switch detail.Name {
+			case "ID":
+				if detail.SQLKey != "primary_key" {
+					t.Errorf("ID should have SQLKey 'primary_key', got '%s'", detail.SQLKey)
+				}
+			case "Username":
+				if detail.SQLKey != "unique" {
+					t.Errorf("Username should have SQLKey 'unique', got '%s'", detail.SQLKey)
+				}
+			case "Email":
+				// The function checks for "unique" first, so uniqueindex is also detected as "unique"
+				// This is expected behavior based on the code logic
+				if detail.SQLKey != "unique" {
+					t.Errorf("Email should have SQLKey 'unique' (uniqueindex contains 'unique'), got '%s'", detail.SQLKey)
+				}
+			}
+		}
+	})
+
+	t.Run("foreign key detection", func(t *testing.T) {
+		// Note: The foreignkey extraction in generic_model.go has a bug where
+		// it requires ik > 0, so foreignkey at the start won't extract the value
+		type FKTestModel struct {
+			ParentID int `gorm:"column:parent_id;foreignkey:rid_parent;association_foreignkey:id_atevent"`
+		}
+
+		model := FKTestModel{}
+		details := GetModelColumnDetail(reflect.ValueOf(model))
+
+		if len(details) == 0 {
+			t.Fatal("Expected at least 1 field")
+		}
+
+		detail := details[0]
+		if detail.SQLKey != "foreign_key" {
+			t.Errorf("Expected SQLKey 'foreign_key', got '%s'", detail.SQLKey)
+		}
+		// Due to the bug in the code (requires ik > 0), the SQLName will be extracted
+		// when foreignkey is not at the beginning of the string
+		if detail.SQLName != "rid_parent" {
+			t.Errorf("Expected SQLName 'rid_parent', got '%s'", detail.SQLName)
+		}
+	})
+}
+
+func TestFnFindKeyVal(t *testing.T) {
+	tests := []struct {
+		name     string
+		src      string
+		key      string
+		expected string
+	}{
+		{
+			name:     "find column",
+			src:      "column:user_id;primaryKey;type:bigint",
+			key:      "column:",
+			expected: "user_id",
+		},
+		{
+			name:     "find type",
+			src:      "column:name;type:varchar(255);not null",
+			key:      "type:",
+			expected: "varchar(255)",
+		},
+		{
+			name:     "key not found",
+			src:      "primaryKey;autoIncrement",
+			key:      "column:",
+			expected: "",
+		},
+		{
+			name:     "key at end without semicolon",
+			src:      "primaryKey;column:id",
+			key:      "column:",
+			expected: "id",
+		},
+		{
+			name:     "case insensitive search",
+			src:      "Column:user_id;primaryKey",
+			key:      "column:",
+			expected: "user_id",
+		},
+		{
+			name:     "empty src",
+			src:      "",
+			key:      "column:",
+			expected: "",
+		},
+		{
+			name:     "multiple occurrences (returns first)",
+			src:      "column:first;column:second",
+			key:      "column:",
+			expected: "first",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := fnFindKeyVal(tt.src, tt.key)
+			if result != tt.expected {
+				t.Errorf("fnFindKeyVal(%q, %q) = %q, want %q", tt.src, tt.key, result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestGetModelColumnDetail_FieldValue(t *testing.T) {
+	model := TestModelForColumnDetail{
+		ID:    123,
+		Name:  "TestName",
+		Email: "test@example.com",
+	}
+
+	details := GetModelColumnDetail(reflect.ValueOf(model))
+
+	for _, detail := range details {
+		if !detail.FieldValue.IsValid() {
+			t.Errorf("Field %s has invalid FieldValue", detail.Name)
+		}
+
+		// Check that FieldValue matches the actual value
+		switch detail.Name {
+		case "ID":
+			if detail.FieldValue.Int() != 123 {
+				t.Errorf("Expected ID FieldValue 123, got %v", detail.FieldValue.Int())
+			}
+		case "Name":
+			if detail.FieldValue.String() != "TestName" {
+				t.Errorf("Expected Name FieldValue 'TestName', got %v", detail.FieldValue.String())
+			}
+		case "Email":
+			if detail.FieldValue.String() != "test@example.com" {
+				t.Errorf("Expected Email FieldValue 'test@example.com', got %v", detail.FieldValue.String())
+			}
+		}
+	}
+}

pkg/reflection/helpers.go

@@ -17,3 +17,33 @@ func Len(v any) int {
 		return 0
 	}
 }
+
+// ExtractTableNameOnly extracts the table name from a fully qualified table reference.
+// It removes any schema prefix (e.g., "schema.table" -> "table") and truncates at
+// the first delimiter (comma, space, tab, or newline). If the input contains multiple
+// dots, it returns everything after the last dot up to the first delimiter.
+func ExtractTableNameOnly(fullName string) string {
+	// First, split by dot to remove schema prefix if present
+	lastDotIndex := -1
+	for i, char := range fullName {
+		if char == '.' {
+			lastDotIndex = i
+		}
+	}
+
+	// Start from after the last dot (or from beginning if no dot)
+	startIndex := 0
+	if lastDotIndex != -1 {
+		startIndex = lastDotIndex + 1
+	}
+
+	// Now find the end (first delimiter after the table name)
+	for i := startIndex; i < len(fullName); i++ {
+		char := rune(fullName[i])
+		if char == ',' || char == ' ' || char == '\t' || char == '\n' {
+			return fullName[startIndex:i]
+		}
+	}
+
+	return fullName[startIndex:]
+}

pkg/reflection/model_utils.go

@@ -1,7 +1,9 @@
 package reflection
 
 import (
+	"fmt"
 	"reflect"
+	"strconv"
 	"strings"
 
 	"github.com/bitechdev/ResolveSpec/pkg/modelregistry"
@@ -132,7 +134,7 @@ func findFieldByName(val reflect.Value, name string) any {
 		}
 
 		// Check if field name matches
-		if strings.ToLower(field.Name) == name && fieldValue.CanInterface() {
+		if strings.EqualFold(field.Name, name) && fieldValue.CanInterface() {
 			return fieldValue.Interface()
 		}
 	}
@@ -323,6 +325,127 @@ func ExtractColumnFromBunTag(tag string) string {
 	return ""
 }
 
+// GetSQLModelColumns extracts column names that have valid SQL field mappings
+// This function only returns columns that:
+// 1. Have bun or gorm tags (not just json tags)
+// 2. Are not relations (no rel:, join:, foreignKey, references, many2many tags)
+// 3. Are not scan-only embedded fields
+func GetSQLModelColumns(model any) []string {
+	var columns []string
+
+	modelType := reflect.TypeOf(model)
+
+	// Unwrap pointers, slices, and arrays to get to the base struct type
+	for modelType != nil && (modelType.Kind() == reflect.Pointer || modelType.Kind() == reflect.Slice || modelType.Kind() == reflect.Array) {
+		modelType = modelType.Elem()
+	}
+
+	// Validate that we have a struct type
+	if modelType == nil || modelType.Kind() != reflect.Struct {
+		return columns
+	}
+
+	collectSQLColumnsFromType(modelType, &columns, false)
+
+	return columns
+}
+
+// collectSQLColumnsFromType recursively collects SQL column names from a struct type
+// scanOnlyEmbedded indicates if we're inside a scan-only embedded struct
+func collectSQLColumnsFromType(typ reflect.Type, columns *[]string, scanOnlyEmbedded bool) {
+	for i := 0; i < typ.NumField(); i++ {
+		field := typ.Field(i)
+
+		// Check if this is an embedded struct
+		if field.Anonymous {
+			// Unwrap pointer type if necessary
+			fieldType := field.Type
+			if fieldType.Kind() == reflect.Pointer {
+				fieldType = fieldType.Elem()
+			}
+
+			// Check if the embedded struct itself is scan-only
+			isScanOnly := scanOnlyEmbedded
+			bunTag := field.Tag.Get("bun")
+			if bunTag != "" && isBunFieldScanOnly(bunTag) {
+				isScanOnly = true
+			}
+
+			// Recursively process embedded struct
+			if fieldType.Kind() == reflect.Struct {
+				collectSQLColumnsFromType(fieldType, columns, isScanOnly)
+				continue
+			}
+		}
+
+		// Skip fields in scan-only embedded structs
+		if scanOnlyEmbedded {
+			continue
+		}
+
+		// Get bun and gorm tags
+		bunTag := field.Tag.Get("bun")
+		gormTag := field.Tag.Get("gorm")
+
+		// Skip if neither bun nor gorm tag exists
+		if bunTag == "" && gormTag == "" {
+			continue
+		}
+
+		// Skip if explicitly marked with "-"
+		if bunTag == "-" || gormTag == "-" {
+			continue
+		}
+
+		// Skip if field itself is scan-only (bun)
+		if bunTag != "" && isBunFieldScanOnly(bunTag) {
+			continue
+		}
+
+		// Skip if field itself is read-only (gorm)
+		if gormTag != "" && isGormFieldReadOnly(gormTag) {
+			continue
+		}
+
+		// Skip relation fields (bun)
+		if bunTag != "" {
+			// Skip if it's a bun relation (rel:, join:, or m2m:)
+			if strings.Contains(bunTag, "rel:") ||
+				strings.Contains(bunTag, "join:") ||
+				strings.Contains(bunTag, "m2m:") {
+				continue
+			}
+		}
+
+		// Skip relation fields (gorm)
+		if gormTag != "" {
+			// Skip if it has gorm relationship tags
+			if strings.Contains(gormTag, "foreignKey:") ||
+				strings.Contains(gormTag, "references:") ||
+				strings.Contains(gormTag, "many2many:") ||
+				strings.Contains(gormTag, "constraint:") {
+				continue
+			}
+		}
+
+		// Get column name
+		columnName := ""
+		if bunTag != "" {
+			columnName = ExtractColumnFromBunTag(bunTag)
+		}
+		if columnName == "" && gormTag != "" {
+			columnName = ExtractColumnFromGormTag(gormTag)
+		}
+
+		// Skip if we couldn't extract a column name
+		if columnName == "" {
+			continue
+		}
+
+		*columns = append(*columns, columnName)
+	}
+}
+
 // IsColumnWritable checks if a column can be written to in the database
 // For bun: returns false if the field has "scanonly" tag
 // For gorm: returns false if the field has "<-:false" or "->" (read-only) tag
@@ -351,7 +474,7 @@ func IsColumnWritable(model any, columnName string) bool {
 
 // isColumnWritableInType recursively searches for a column and checks if it's writable
 // Returns (found, writable) where found indicates if the column was found
-func isColumnWritableInType(typ reflect.Type, columnName string) (bool, bool) {
+func isColumnWritableInType(typ reflect.Type, columnName string) (found bool, writable bool) {
 	for i := 0; i < typ.NumField(); i++ {
 		field := typ.Field(i)
 
@@ -440,3 +563,433 @@ func isGormFieldReadOnly(tag string) bool {
 	}
 	return false
 }
+
+// ExtractSourceColumn extracts the base column name from PostgreSQL JSON operators
+// Examples:
+//   - "columna->>'val'" returns "columna"
+//   - "columna->'key'" returns "columna"
+//   - "columna" returns "columna"
+//   - "table.columna->>'val'" returns "table.columna"
+func ExtractSourceColumn(colName string) string {
+	// Check for PostgreSQL JSON operators: -> and ->>
+	if idx := strings.Index(colName, "->>"); idx != -1 {
+		return strings.TrimSpace(colName[:idx])
+	}
+	if idx := strings.Index(colName, "->"); idx != -1 {
+		return strings.TrimSpace(colName[:idx])
+	}
+	return colName
+}
+
+// ToSnakeCase converts a string from CamelCase to snake_case
+func ToSnakeCase(s string) string {
+	var result strings.Builder
+	for i, r := range s {
+		if i > 0 && r >= 'A' && r <= 'Z' {
+			result.WriteRune('_')
+		}
+		result.WriteRune(r)
+	}
+	return strings.ToLower(result.String())
+}
+
+// GetColumnTypeFromModel uses reflection to determine the Go type of a column in a model
+func GetColumnTypeFromModel(model interface{}, colName string) reflect.Kind {
+	if model == nil {
+		return reflect.Invalid
+	}
+
+	// Extract the source column name (remove JSON operators like ->> or ->)
+	sourceColName := ExtractSourceColumn(colName)
+
+	modelType := reflect.TypeOf(model)
+	// Dereference pointer if needed
+	if modelType.Kind() == reflect.Ptr {
+		modelType = modelType.Elem()
+	}
+
+	// Ensure it's a struct
+	if modelType.Kind() != reflect.Struct {
+		return reflect.Invalid
+	}
+
+	// Find the field by JSON tag or field name
+	for i := 0; i < modelType.NumField(); i++ {
+		field := modelType.Field(i)
+
+		// Check JSON tag
+		jsonTag := field.Tag.Get("json")
+		if jsonTag != "" {
+			// Parse JSON tag (format: "name,omitempty")
+			parts := strings.Split(jsonTag, ",")
+			if parts[0] == sourceColName {
+				return field.Type.Kind()
+			}
+		}
+
+		// Check field name (case-insensitive)
+		if strings.EqualFold(field.Name, sourceColName) {
+			return field.Type.Kind()
+		}
+
+		// Check snake_case conversion
+		snakeCaseName := ToSnakeCase(field.Name)
+		if snakeCaseName == sourceColName {
+			return field.Type.Kind()
+		}
+	}
+
+	return reflect.Invalid
+}
+
+// IsNumericType checks if a reflect.Kind is a numeric type
+func IsNumericType(kind reflect.Kind) bool {
+	return kind == reflect.Int || kind == reflect.Int8 || kind == reflect.Int16 ||
+		kind == reflect.Int32 || kind == reflect.Int64 || kind == reflect.Uint ||
+		kind == reflect.Uint8 || kind == reflect.Uint16 || kind == reflect.Uint32 ||
+		kind == reflect.Uint64 || kind == reflect.Float32 || kind == reflect.Float64
+}
+
+// IsStringType checks if a reflect.Kind is a string type
+func IsStringType(kind reflect.Kind) bool {
+	return kind == reflect.String
+}
+
+// IsNumericValue checks if a string value can be parsed as a number
+func IsNumericValue(value string) bool {
+	value = strings.TrimSpace(value)
+	_, err := strconv.ParseFloat(value, 64)
+	return err == nil
+}
+
+// ConvertToNumericType converts a string value to the appropriate numeric type
+func ConvertToNumericType(value string, kind reflect.Kind) (interface{}, error) {
+	value = strings.TrimSpace(value)
+
+	switch kind {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		// Parse as integer
+		bitSize := 64
+		switch kind {
+		case reflect.Int8:
+			bitSize = 8
+		case reflect.Int16:
+			bitSize = 16
+		case reflect.Int32:
+			bitSize = 32
+		}
+
+		intVal, err := strconv.ParseInt(value, 10, bitSize)
+		if err != nil {
+			return nil, fmt.Errorf("invalid integer value: %w", err)
+		}
+
+		// Return the appropriate type
+		switch kind {
+		case reflect.Int:
+			return int(intVal), nil
+		case reflect.Int8:
+			return int8(intVal), nil
+		case reflect.Int16:
+			return int16(intVal), nil
+		case reflect.Int32:
+			return int32(intVal), nil
+		case reflect.Int64:
+			return intVal, nil
+		}
+
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		// Parse as unsigned integer
+		bitSize := 64
+		switch kind {
+		case reflect.Uint8:
+			bitSize = 8
+		case reflect.Uint16:
+			bitSize = 16
+		case reflect.Uint32:
+			bitSize = 32
+		}
+
+		uintVal, err := strconv.ParseUint(value, 10, bitSize)
+		if err != nil {
+			return nil, fmt.Errorf("invalid unsigned integer value: %w", err)
+		}
+
+		// Return the appropriate type
+		switch kind {
+		case reflect.Uint:
+			return uint(uintVal), nil
+		case reflect.Uint8:
+			return uint8(uintVal), nil
+		case reflect.Uint16:
+			return uint16(uintVal), nil
+		case reflect.Uint32:
+			return uint32(uintVal), nil
+		case reflect.Uint64:
+			return uintVal, nil
+		}
+
+	case reflect.Float32, reflect.Float64:
+		// Parse as float
+		bitSize := 64
+		if kind == reflect.Float32 {
+			bitSize = 32
+		}
+
+		floatVal, err := strconv.ParseFloat(value, bitSize)
+		if err != nil {
+			return nil, fmt.Errorf("invalid float value: %w", err)
+		}
+
+		if kind == reflect.Float32 {
+			return float32(floatVal), nil
+		}
+		return floatVal, nil
+	}
+
+	return nil, fmt.Errorf("unsupported numeric type: %v", kind)
+}
+
+// RelationType represents the type of database relationship
+type RelationType string
+
+const (
+	RelationHasMany    RelationType = "has-many"     // 1:N - use separate query
+	RelationBelongsTo  RelationType = "belongs-to"   // N:1 - use JOIN
+	RelationHasOne     RelationType = "has-one"      // 1:1 - use JOIN
+	RelationManyToMany RelationType = "many-to-many" // M:N - use separate query
+	RelationUnknown    RelationType = "unknown"
+)
+
+// ShouldUseJoin returns true if the relation type should use a JOIN instead of separate query
+func (rt RelationType) ShouldUseJoin() bool {
+	return rt == RelationBelongsTo || rt == RelationHasOne
+}
+
+// GetRelationType inspects the model's struct tags to determine the relationship type
+// It checks both Bun and GORM tags to identify the relationship cardinality
+func GetRelationType(model interface{}, fieldName string) RelationType {
+	if model == nil || fieldName == "" {
+		return RelationUnknown
+	}
+
+	modelType := reflect.TypeOf(model)
+	if modelType == nil {
+		return RelationUnknown
+	}
+
+	if modelType.Kind() == reflect.Ptr {
+		modelType = modelType.Elem()
+	}
+
+	if modelType == nil || modelType.Kind() != reflect.Struct {
+		return RelationUnknown
+	}
+
+	// Find the field
+	for i := 0; i < modelType.NumField(); i++ {
+		field := modelType.Field(i)
+
+		// Check if field name matches (case-insensitive)
+		if !strings.EqualFold(field.Name, fieldName) {
+			continue
+		}
+
+		// Check Bun tags first
+		bunTag := field.Tag.Get("bun")
+		if bunTag != "" && strings.Contains(bunTag, "rel:") {
+			// Parse bun relation tag: rel:has-many, rel:belongs-to, rel:has-one, rel:many-to-many
+			parts := strings.Split(bunTag, ",")
+			for _, part := range parts {
+				part = strings.TrimSpace(part)
+				if strings.HasPrefix(part, "rel:") {
+					relType := strings.TrimPrefix(part, "rel:")
+					switch relType {
+					case "has-many":
+						return RelationHasMany
+					case "belongs-to":
+						return RelationBelongsTo
+					case "has-one":
+						return RelationHasOne
+					case "many-to-many", "m2m":
+						return RelationManyToMany
+					}
+				}
+			}
+		}
+
+		// Check GORM tags
+		gormTag := field.Tag.Get("gorm")
+		if gormTag != "" {
+			// GORM uses different patterns:
+			// - foreignKey: usually indicates belongs-to or has-one
+			// - many2many: indicates many-to-many
+			// - Field type (slice vs pointer) helps determine cardinality
+
+			if strings.Contains(gormTag, "many2many:") {
+				return RelationManyToMany
+			}
+
+			// Check field type for cardinality hints
+			fieldType := field.Type
+			if fieldType.Kind() == reflect.Slice {
+				// Slice indicates has-many or many-to-many
+				return RelationHasMany
+			}
+			if fieldType.Kind() == reflect.Ptr {
+				// Pointer to single struct usually indicates belongs-to or has-one
+				// Check if it has foreignKey (belongs-to) or references (has-one)
+				if strings.Contains(gormTag, "foreignKey:") {
+					return RelationBelongsTo
+				}
+				return RelationHasOne
+			}
+		}
+
+		// Fall back to field type inference
+		fieldType := field.Type
+		if fieldType.Kind() == reflect.Slice {
+			// Slice of structs → has-many
+			return RelationHasMany
+		}
+		if fieldType.Kind() == reflect.Ptr || fieldType.Kind() == reflect.Struct {
+			// Single struct → belongs-to (default assumption for safety)
+			// Using belongs-to as default ensures we use JOIN, which is safer
+			return RelationBelongsTo
+		}
+	}
+
+	return RelationUnknown
+}
+
+// GetRelationModel gets the model type for a relation field
+// It searches for the field by name in the following order (case-insensitive):
+// 1. Actual field name
+// 2. Bun tag name (if exists)
+// 3. Gorm tag name (if exists)
+// 4. JSON tag name (if exists)
+//
+// Supports recursive field paths using dot notation (e.g., "MAL.MAL.DEF")
+// For nested fields, it traverses through each level of the struct hierarchy
+func GetRelationModel(model interface{}, fieldName string) interface{} {
+	if model == nil || fieldName == "" {
+		return nil
+	}
+
+	// Split the field name by "." to handle nested/recursive relations
+	fieldParts := strings.Split(fieldName, ".")
+
+	// Start with the current model
+	currentModel := model
+
+	// Traverse through each level of the field path
+	for _, part := range fieldParts {
+		if part == "" {
+			continue
+		}
+
+		currentModel = getRelationModelSingleLevel(currentModel, part)
+		if currentModel == nil {
+			return nil
+		}
+	}
+
+	return currentModel
+}
+
+// getRelationModelSingleLevel gets the model type for a single level field (non-recursive)
+// This is a helper function used by GetRelationModel to handle one level at a time
+func getRelationModelSingleLevel(model interface{}, fieldName string) interface{} {
+	if model == nil || fieldName == "" {
+		return nil
+	}
+
+	modelType := reflect.TypeOf(model)
+	if modelType == nil {
+		return nil
+	}
+
+	if modelType.Kind() == reflect.Ptr {
+		modelType = modelType.Elem()
+	}
+
+	if modelType == nil || modelType.Kind() != reflect.Struct {
+		return nil
+	}
+
+	// Find the field by checking in priority order (case-insensitive)
+	var field *reflect.StructField
+	normalizedFieldName := strings.ToLower(fieldName)
+
+	for i := 0; i < modelType.NumField(); i++ {
+		f := modelType.Field(i)
+
+		// 1. Check actual field name (case-insensitive)
+		if strings.EqualFold(f.Name, fieldName) {
+			field = &f
+			break
+		}
+
+		// 2. Check bun tag name
+		bunTag := f.Tag.Get("bun")
+		if bunTag != "" {
+			bunColName := ExtractColumnFromBunTag(bunTag)
+			if bunColName != "" && strings.EqualFold(bunColName, normalizedFieldName) {
+				field = &f
+				break
+			}
+		}
+
+		// 3. Check gorm tag name
+		gormTag := f.Tag.Get("gorm")
+		if gormTag != "" {
+			gormColName := ExtractColumnFromGormTag(gormTag)
+			if gormColName != "" && strings.EqualFold(gormColName, normalizedFieldName) {
+				field = &f
+				break
+			}
+		}
+
+		// 4. Check JSON tag name
+		jsonTag := f.Tag.Get("json")
+		if jsonTag != "" {
+			parts := strings.Split(jsonTag, ",")
+			if len(parts) > 0 && parts[0] != "" && parts[0] != "-" {
+				if strings.EqualFold(parts[0], normalizedFieldName) {
+					field = &f
+					break
+				}
+			}
+		}
+	}
+
+	if field == nil {
+		return nil
+	}
+
+	// Get the target type
+	targetType := field.Type
+	if targetType == nil {
+		return nil
+	}
+
+	if targetType.Kind() == reflect.Slice {
+		targetType = targetType.Elem()
+		if targetType == nil {
+			return nil
+		}
+	}
+	if targetType.Kind() == reflect.Ptr {
+		targetType = targetType.Elem()
+		if targetType == nil {
+			return nil
+		}
+	}
+
+	if targetType.Kind() != reflect.Struct {
+		return nil
+	}
+
+	// Create a zero value of the target type
+	return reflect.New(targetType).Elem().Interface()
+}

pkg/resolvespec/context_test.go

@@ -0,0 +1,138 @@
+package resolvespec
+
+import (
+	"context"
+	"testing"
+)
+
+func TestContextOperations(t *testing.T) {
+	ctx := context.Background()
+
+	// Test Schema
+	t.Run("WithSchema and GetSchema", func(t *testing.T) {
+		ctx = WithSchema(ctx, "public")
+		schema := GetSchema(ctx)
+		if schema != "public" {
+			t.Errorf("Expected schema 'public', got '%s'", schema)
+		}
+	})
+
+	// Test Entity
+	t.Run("WithEntity and GetEntity", func(t *testing.T) {
+		ctx = WithEntity(ctx, "users")
+		entity := GetEntity(ctx)
+		if entity != "users" {
+			t.Errorf("Expected entity 'users', got '%s'", entity)
+		}
+	})
+
+	// Test TableName
+	t.Run("WithTableName and GetTableName", func(t *testing.T) {
+		ctx = WithTableName(ctx, "public.users")
+		tableName := GetTableName(ctx)
+		if tableName != "public.users" {
+			t.Errorf("Expected tableName 'public.users', got '%s'", tableName)
+		}
+	})
+
+	// Test Model
+	t.Run("WithModel and GetModel", func(t *testing.T) {
+		type TestModel struct {
+			ID   int
+			Name string
+		}
+		model := &TestModel{ID: 1, Name: "test"}
+		ctx = WithModel(ctx, model)
+		retrieved := GetModel(ctx)
+		if retrieved == nil {
+			t.Error("Expected model to be retrieved, got nil")
+		}
+		if retrievedModel, ok := retrieved.(*TestModel); ok {
+			if retrievedModel.ID != 1 || retrievedModel.Name != "test" {
+				t.Errorf("Expected model with ID=1 and Name='test', got ID=%d, Name='%s'", retrievedModel.ID, retrievedModel.Name)
+			}
+		} else {
+			t.Error("Retrieved model is not of expected type")
+		}
+	})
+
+	// Test ModelPtr
+	t.Run("WithModelPtr and GetModelPtr", func(t *testing.T) {
+		type TestModel struct {
+			ID int
+		}
+		models := []*TestModel{}
+		ctx = WithModelPtr(ctx, &models)
+		retrieved := GetModelPtr(ctx)
+		if retrieved == nil {
+			t.Error("Expected modelPtr to be retrieved, got nil")
+		}
+	})
+
+	// Test WithRequestData
+	t.Run("WithRequestData", func(t *testing.T) {
+		type TestModel struct {
+			ID   int
+			Name string
+		}
+		model := &TestModel{ID: 1, Name: "test"}
+		modelPtr := &[]*TestModel{}
+
+		ctx = WithRequestData(ctx, "test_schema", "test_entity", "test_schema.test_entity", model, modelPtr)
+
+		if GetSchema(ctx) != "test_schema" {
+			t.Errorf("Expected schema 'test_schema', got '%s'", GetSchema(ctx))
+		}
+		if GetEntity(ctx) != "test_entity" {
+			t.Errorf("Expected entity 'test_entity', got '%s'", GetEntity(ctx))
+		}
+		if GetTableName(ctx) != "test_schema.test_entity" {
+			t.Errorf("Expected tableName 'test_schema.test_entity', got '%s'", GetTableName(ctx))
+		}
+		if GetModel(ctx) == nil {
+			t.Error("Expected model to be set")
+		}
+		if GetModelPtr(ctx) == nil {
+			t.Error("Expected modelPtr to be set")
+		}
+	})
+}
+
+func TestEmptyContext(t *testing.T) {
+	ctx := context.Background()
+
+	t.Run("GetSchema with empty context", func(t *testing.T) {
+		schema := GetSchema(ctx)
+		if schema != "" {
+			t.Errorf("Expected empty schema, got '%s'", schema)
+		}
+	})
+
+	t.Run("GetEntity with empty context", func(t *testing.T) {
+		entity := GetEntity(ctx)
+		if entity != "" {
+			t.Errorf("Expected empty entity, got '%s'", entity)
+		}
+	})
+
+	t.Run("GetTableName with empty context", func(t *testing.T) {
+		tableName := GetTableName(ctx)
+		if tableName != "" {
+			t.Errorf("Expected empty tableName, got '%s'", tableName)
+		}
+	})
+
+	t.Run("GetModel with empty context", func(t *testing.T) {
+		model := GetModel(ctx)
+		if model != nil {
+			t.Errorf("Expected nil model, got %v", model)
+		}
+	})
+
+	t.Run("GetModelPtr with empty context", func(t *testing.T) {
+		modelPtr := GetModelPtr(ctx)
+		if modelPtr != nil {
+			t.Errorf("Expected nil modelPtr, got %v", modelPtr)
+		}
+	})
+}

pkg/resolvespec/cursor.go

@@ -0,0 +1,179 @@
+package resolvespec
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
+)
+
+// CursorDirection defines pagination direction
+type CursorDirection int
+
+const (
+	CursorForward  CursorDirection = 1
+	CursorBackward CursorDirection = -1
+)
+
+// GetCursorFilter generates a SQL `EXISTS` subquery for cursor-based pagination.
+// It uses the current request's sort and cursor values.
+//
+// Parameters:
+//   - tableName: name of the main table (e.g. "posts")
+//   - pkName: primary key column (e.g. "id")
+//   - modelColumns: optional list of valid main-table columns (for validation). Pass nil to skip.
+//   - options: the request options containing sort and cursor information
+//
+// Returns SQL snippet to embed in WHERE clause.
+func GetCursorFilter(
+	tableName string,
+	pkName string,
+	modelColumns []string,
+	options common.RequestOptions,
+) (string, error) {
+	// Remove schema prefix if present
+	if strings.Contains(tableName, ".") {
+		tableName = strings.SplitN(tableName, ".", 2)[1]
+	}
+
+	// --------------------------------------------------------------------- //
+	// 1. Determine active cursor
+	// --------------------------------------------------------------------- //
+	cursorID, direction := getActiveCursor(options)
+	if cursorID == "" {
+		return "", fmt.Errorf("no cursor provided for table %s", tableName)
+	}
+
+	// --------------------------------------------------------------------- //
+	// 2. Extract sort columns
+	// --------------------------------------------------------------------- //
+	sortItems := options.Sort
+	if len(sortItems) == 0 {
+		return "", fmt.Errorf("no sort columns defined")
+	}
+
+	// --------------------------------------------------------------------- //
+	// 3. Prepare
+	// --------------------------------------------------------------------- //
+	var whereClauses []string
+	reverse := direction < 0
+
+	// --------------------------------------------------------------------- //
+	// 4. Process each sort column
+	// --------------------------------------------------------------------- //
+	for _, s := range sortItems {
+		col := strings.TrimSpace(s.Column)
+		if col == "" {
+			continue
+		}
+
+		// Parse: "created_at", "user.name", etc.
+		parts := strings.Split(col, ".")
+		field := strings.TrimSpace(parts[len(parts)-1])
+		prefix := strings.Join(parts[:len(parts)-1], ".")
+
+		// Direction from struct
+		desc := strings.EqualFold(s.Direction, "desc")
+
+		if reverse {
+			desc = !desc
+		}
+
+		// Resolve column
+		cursorCol, targetCol, err := resolveColumn(
+			field, prefix, tableName, modelColumns,
+		)
+		if err != nil {
+			logger.Warn("Skipping invalid sort column %q: %v", col, err)
+			continue
+		}
+
+		// Build inequality
+		op := "<"
+		if desc {
+			op = ">"
+		}
+		whereClauses = append(whereClauses, fmt.Sprintf("%s %s %s", cursorCol, op, targetCol))
+	}
+
+	if len(whereClauses) == 0 {
+		return "", fmt.Errorf("no valid sort columns after filtering")
+	}
+
+	// --------------------------------------------------------------------- //
+	// 5. Build priority OR-AND chain
+	// --------------------------------------------------------------------- //
+	orSQL := buildPriorityChain(whereClauses)
+
+	// --------------------------------------------------------------------- //
+	// 6. Final EXISTS subquery
+	// --------------------------------------------------------------------- //
+	query := fmt.Sprintf(`EXISTS (
+  SELECT 1
+  FROM %s cursor_select
+  WHERE cursor_select.%s = %s
+    AND (%s)
+)`,
+		tableName,
+		pkName,
+		cursorID,
+		orSQL,
+	)
+
+	return query, nil
+}
+
+// ------------------------------------------------------------------------- //
+// Helper: get active cursor (forward or backward)
+func getActiveCursor(options common.RequestOptions) (id string, direction CursorDirection) {
+	if options.CursorForward != "" {
+		return options.CursorForward, CursorForward
+	}
+	if options.CursorBackward != "" {
+		return options.CursorBackward, CursorBackward
+	}
+	return "", 0
+}
+
+// Helper: resolve column (main table only for now)
+func resolveColumn(
+	field, prefix, tableName string,
+	modelColumns []string,
+) (cursorCol, targetCol string, err error) {
+
+	// JSON field
+	if strings.Contains(field, "->") {
+		return "cursor_select." + field, tableName + "." + field, nil
+	}
+
+	// Main table column
+	if modelColumns != nil {
+		for _, col := range modelColumns {
+			if strings.EqualFold(col, field) {
+				return "cursor_select." + field, tableName + "." + field, nil
+			}
+		}
+	} else {
+		// No validation → allow all main-table fields
+		return "cursor_select." + field, tableName + "." + field, nil
+	}
+
+	// Joined column (not supported in resolvespec yet)
+	if prefix != "" && prefix != tableName {
+		return "", "", fmt.Errorf("joined columns not supported in cursor pagination: %s", field)
+	}
+
+	return "", "", fmt.Errorf("invalid column: %s", field)
+}
+
+// ------------------------------------------------------------------------- //
+// Helper: build OR-AND priority chain
+func buildPriorityChain(clauses []string) string {
+	var or []string
+	for i := 0; i < len(clauses); i++ {
+		and := strings.Join(clauses[:i+1], "\n    AND ")
+		or = append(or, "("+and+")")
+	}
+	return strings.Join(or, "\n  OR ")
+}

pkg/resolvespec/cursor_test.go

@@ -0,0 +1,378 @@
+package resolvespec
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+)
+
+func TestGetCursorFilter_Forward(t *testing.T) {
+	options := common.RequestOptions{
+		Sort: []common.SortOption{
+			{Column: "created_at", Direction: "DESC"},
+			{Column: "id", Direction: "ASC"},
+		},
+		CursorForward: "123",
+	}
+
+	tableName := "posts"
+	pkName := "id"
+	modelColumns := []string{"id", "title", "created_at", "user_id"}
+
+	filter, err := GetCursorFilter(tableName, pkName, modelColumns, options)
+	if err != nil {
+		t.Fatalf("GetCursorFilter failed: %v", err)
+	}
+
+	if filter == "" {
+		t.Fatal("Expected non-empty cursor filter")
+	}
+
+	// Verify filter contains EXISTS subquery
+	if !strings.Contains(filter, "EXISTS") {
+		t.Errorf("Filter should contain EXISTS subquery, got: %s", filter)
+	}
+
+	// Verify filter references the cursor ID
+	if !strings.Contains(filter, "123") {
+		t.Errorf("Filter should reference cursor ID 123, got: %s", filter)
+	}
+
+	// Verify filter contains the table name
+	if !strings.Contains(filter, tableName) {
+		t.Errorf("Filter should reference table name %s, got: %s", tableName, filter)
+	}
+
+	// Verify filter contains primary key
+	if !strings.Contains(filter, pkName) {
+		t.Errorf("Filter should reference primary key %s, got: %s", pkName, filter)
+	}
+
+	t.Logf("Generated cursor filter: %s", filter)
+}
+
+func TestGetCursorFilter_Backward(t *testing.T) {
+	options := common.RequestOptions{
+		Sort: []common.SortOption{
+			{Column: "created_at", Direction: "DESC"},
+			{Column: "id", Direction: "ASC"},
+		},
+		CursorBackward: "456",
+	}
+
+	tableName := "posts"
+	pkName := "id"
+	modelColumns := []string{"id", "title", "created_at", "user_id"}
+
+	filter, err := GetCursorFilter(tableName, pkName, modelColumns, options)
+	if err != nil {
+		t.Fatalf("GetCursorFilter failed: %v", err)
+	}
+
+	if filter == "" {
+		t.Fatal("Expected non-empty cursor filter")
+	}
+
+	// Verify filter contains cursor ID
+	if !strings.Contains(filter, "456") {
+		t.Errorf("Filter should reference cursor ID 456, got: %s", filter)
+	}
+
+	// For backward cursor, sort direction should be reversed
+	// This is handled internally by the GetCursorFilter function
+	t.Logf("Generated backward cursor filter: %s", filter)
+}
+
+func TestGetCursorFilter_NoCursor(t *testing.T) {
+	options := common.RequestOptions{
+		Sort: []common.SortOption{
+			{Column: "created_at", Direction: "DESC"},
+		},
+		// No cursor set
+	}
+
+	tableName := "posts"
+	pkName := "id"
+	modelColumns := []string{"id", "title", "created_at"}
+
+	_, err := GetCursorFilter(tableName, pkName, modelColumns, options)
+	if err == nil {
+		t.Error("Expected error when no cursor is provided")
+	}
+
+	if !strings.Contains(err.Error(), "no cursor provided") {
+		t.Errorf("Expected 'no cursor provided' error, got: %v", err)
+	}
+}
+
+func TestGetCursorFilter_NoSort(t *testing.T) {
+	options := common.RequestOptions{
+		Sort:          []common.SortOption{},
+		CursorForward: "123",
+	}
+
+	tableName := "posts"
+	pkName := "id"
+	modelColumns := []string{"id", "title"}
+
+	_, err := GetCursorFilter(tableName, pkName, modelColumns, options)
+	if err == nil {
+		t.Error("Expected error when no sort columns are defined")
+	}
+
+	if !strings.Contains(err.Error(), "no sort columns") {
+		t.Errorf("Expected 'no sort columns' error, got: %v", err)
+	}
+}
+
+func TestGetCursorFilter_MultiColumnSort(t *testing.T) {
+	options := common.RequestOptions{
+		Sort: []common.SortOption{
+			{Column: "priority", Direction: "DESC"},
+			{Column: "created_at", Direction: "DESC"},
+			{Column: "id", Direction: "ASC"},
+		},
+		CursorForward: "789",
+	}
+
+	tableName := "tasks"
+	pkName := "id"
+	modelColumns := []string{"id", "title", "priority", "created_at"}
+
+	filter, err := GetCursorFilter(tableName, pkName, modelColumns, options)
+	if err != nil {
+		t.Fatalf("GetCursorFilter failed: %v", err)
+	}
+
+	// Verify filter contains priority column
+	if !strings.Contains(filter, "priority") {
+		t.Errorf("Filter should reference priority column, got: %s", filter)
+	}
+
+	// Verify filter contains created_at column
+	if !strings.Contains(filter, "created_at") {
+		t.Errorf("Filter should reference created_at column, got: %s", filter)
+	}
+
+	t.Logf("Generated multi-column cursor filter: %s", filter)
+}
+
+func TestGetCursorFilter_WithSchemaPrefix(t *testing.T) {
+	options := common.RequestOptions{
+		Sort: []common.SortOption{
+			{Column: "name", Direction: "ASC"},
+		},
+		CursorForward: "100",
+	}
+
+	tableName := "public.users"
+	pkName := "id"
+	modelColumns := []string{"id", "name", "email"}
+
+	filter, err := GetCursorFilter(tableName, pkName, modelColumns, options)
+	if err != nil {
+		t.Fatalf("GetCursorFilter failed: %v", err)
+	}
+
+	// Should handle schema prefix properly
+	if !strings.Contains(filter, "users") {
+		t.Errorf("Filter should reference table name users, got: %s", filter)
+	}
+
+	t.Logf("Generated cursor filter with schema: %s", filter)
+}
+
+func TestGetActiveCursor(t *testing.T) {
+	tests := []struct {
+		name              string
+		options           common.RequestOptions
+		expectedID        string
+		expectedDirection CursorDirection
+	}{
+		{
+			name: "Forward cursor only",
+			options: common.RequestOptions{
+				CursorForward: "123",
+			},
+			expectedID:        "123",
+			expectedDirection: CursorForward,
+		},
+		{
+			name: "Backward cursor only",
+			options: common.RequestOptions{
+				CursorBackward: "456",
+			},
+			expectedID:        "456",
+			expectedDirection: CursorBackward,
+		},
+		{
+			name: "Both cursors - forward takes precedence",
+			options: common.RequestOptions{
+				CursorForward:  "123",
+				CursorBackward: "456",
+			},
+			expectedID:        "123",
+			expectedDirection: CursorForward,
+		},
+		{
+			name:              "No cursors",
+			options:           common.RequestOptions{},
+			expectedID:        "",
+			expectedDirection: 0,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			id, direction := getActiveCursor(tt.options)
+
+			if id != tt.expectedID {
+				t.Errorf("Expected cursor ID %q, got %q", tt.expectedID, id)
+			}
+
+			if direction != tt.expectedDirection {
+				t.Errorf("Expected direction %d, got %d", tt.expectedDirection, direction)
+			}
+		})
+	}
+}
+
+func TestResolveColumn(t *testing.T) {
+	tests := []struct {
+		name         string
+		field        string
+		prefix       string
+		tableName    string
+		modelColumns []string
+		wantCursor   string
+		wantTarget   string
+		wantErr      bool
+	}{
+		{
+			name:         "Simple column",
+			field:        "id",
+			prefix:       "",
+			tableName:    "users",
+			modelColumns: []string{"id", "name", "email"},
+			wantCursor:   "cursor_select.id",
+			wantTarget:   "users.id",
+			wantErr:      false,
+		},
+		{
+			name:         "Column with case insensitive match",
+			field:        "NAME",
+			prefix:       "",
+			tableName:    "users",
+			modelColumns: []string{"id", "name", "email"},
+			wantCursor:   "cursor_select.NAME",
+			wantTarget:   "users.NAME",
+			wantErr:      false,
+		},
+		{
+			name:         "Invalid column",
+			field:        "invalid_field",
+			prefix:       "",
+			tableName:    "users",
+			modelColumns: []string{"id", "name", "email"},
+			wantErr:      true,
+		},
+		{
+			name:         "JSON field",
+			field:        "metadata->>'key'",
+			prefix:       "",
+			tableName:    "posts",
+			modelColumns: []string{"id", "metadata"},
+			wantCursor:   "cursor_select.metadata->>'key'",
+			wantTarget:   "posts.metadata->>'key'",
+			wantErr:      false,
+		},
+		{
+			name:         "Joined column (not supported)",
+			field:        "name",
+			prefix:       "user",
+			tableName:    "posts",
+			modelColumns: []string{"id", "title"},
+			wantErr:      true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cursor, target, err := resolveColumn(tt.field, tt.prefix, tt.tableName, tt.modelColumns)
+
+			if tt.wantErr {
+				if err == nil {
+					t.Error("Expected error but got none")
+				}
+				return
+			}
+
+			if err != nil {
+				t.Fatalf("Unexpected error: %v", err)
+			}
+
+			if cursor != tt.wantCursor {
+				t.Errorf("Expected cursor %q, got %q", tt.wantCursor, cursor)
+			}
+
+			if target != tt.wantTarget {
+				t.Errorf("Expected target %q, got %q", tt.wantTarget, target)
+			}
+		})
+	}
+}
+
+func TestBuildPriorityChain(t *testing.T) {
+	clauses := []string{
+		"cursor_select.priority > tasks.priority",
+		"cursor_select.created_at > tasks.created_at",
+		"cursor_select.id < tasks.id",
+	}
+
+	result := buildPriorityChain(clauses)
+
+	// Should build OR-AND chain for cursor comparison
+	if !strings.Contains(result, "OR") {
+		t.Error("Priority chain should contain OR operators")
+	}
+
+	if !strings.Contains(result, "AND") {
+		t.Error("Priority chain should contain AND operators for composite conditions")
+	}
+
+	// First clause should appear standalone
+	if !strings.Contains(result, clauses[0]) {
+		t.Errorf("Priority chain should contain first clause: %s", clauses[0])
+	}
+
+	t.Logf("Built priority chain: %s", result)
+}
+
+func TestCursorFilter_SQL_Safety(t *testing.T) {
+	// Test that cursor filter doesn't allow SQL injection
+	options := common.RequestOptions{
+		Sort: []common.SortOption{
+			{Column: "created_at", Direction: "DESC"},
+		},
+		CursorForward: "123; DROP TABLE users; --",
+	}
+
+	tableName := "posts"
+	pkName := "id"
+	modelColumns := []string{"id", "created_at"}
+
+	filter, err := GetCursorFilter(tableName, pkName, modelColumns, options)
+	if err != nil {
+		t.Fatalf("GetCursorFilter failed: %v", err)
+	}
+
+	// The cursor ID is inserted directly into the query
+	// This should be sanitized by the sanitizeWhereClause function in the handler
+	// For now, just verify it generates a filter
+	if filter == "" {
+		t.Error("Expected non-empty cursor filter even with special characters")
+	}
+
+	t.Logf("Generated filter with special chars in cursor: %s", filter)
+}

pkg/resolvespec/handler.go

@@ -8,17 +8,26 @@ import (
 	"reflect"
 	"runtime/debug"
 	"strings"
+	"time"
 
+	"github.com/bitechdev/ResolveSpec/pkg/cache"
 	"github.com/bitechdev/ResolveSpec/pkg/common"
 	"github.com/bitechdev/ResolveSpec/pkg/logger"
 	"github.com/bitechdev/ResolveSpec/pkg/reflection"
 )
 
+// FallbackHandler is a function that handles requests when no model is found
+// It receives the same parameters as the Handle method
+type FallbackHandler func(w common.ResponseWriter, r common.Request, params map[string]string)
+
 // Handler handles API requests using database and model abstractions
 type Handler struct {
-	db              common.Database
-	registry        common.ModelRegistry
-	nestedProcessor *common.NestedCUDProcessor
+	db               common.Database
+	registry         common.ModelRegistry
+	nestedProcessor  *common.NestedCUDProcessor
+	hooks            *HookRegistry
+	fallbackHandler  FallbackHandler
+	openAPIGenerator func() (string, error)
 }
 
 // NewHandler creates a new API handler with database and registry abstractions
@@ -26,12 +35,31 @@ func NewHandler(db common.Database, registry common.ModelRegistry) *Handler {
 	handler := &Handler{
 		db:       db,
 		registry: registry,
+		hooks:    NewHookRegistry(),
 	}
 	// Initialize nested processor
 	handler.nestedProcessor = common.NewNestedCUDProcessor(db, registry, handler)
 	return handler
 }
 
+// Hooks returns the hook registry for this handler
+// Use this to register custom hooks for operations
+func (h *Handler) Hooks() *HookRegistry {
+	return h.hooks
+}
+
+// SetFallbackHandler sets a fallback handler to be called when no model is found
+// If not set, the handler will simply return (pass through to next route)
+func (h *Handler) SetFallbackHandler(fallback FallbackHandler) {
+	h.fallbackHandler = fallback
+}
+
+// GetDatabase returns the underlying database connection
+// Implements common.SpecHandler interface
+func (h *Handler) GetDatabase() common.Database {
+	return h.db
+}
+
 // handlePanic is a helper function to handle panics with stack traces
 func (h *Handler) handlePanic(w common.ResponseWriter, method string, err interface{}) {
 	stack := debug.Stack()
@@ -48,7 +76,13 @@ func (h *Handler) Handle(w common.ResponseWriter, r common.Request, params map[s
 		}
 	}()
 
-	ctx := context.Background()
+	// Check for ?openapi query parameter
+	if r.UnderlyingRequest().URL.Query().Get("openapi") != "" {
+		h.HandleOpenAPI(w, r)
+		return
+	}
+
+	ctx := r.UnderlyingRequest().Context()
 
 	body, err := r.Body()
 	if err != nil {
@@ -73,33 +107,27 @@ func (h *Handler) Handle(w common.ResponseWriter, r common.Request, params map[s
 	// Get model and populate context with request-scoped data
 	model, err := h.registry.GetModelByEntity(schema, entity)
 	if err != nil {
-		logger.Error("Invalid entity: %v", err)
-		h.sendError(w, http.StatusBadRequest, "invalid_entity", "Invalid entity", err)
+		// Model not found - call fallback handler if set, otherwise pass through
+		logger.Debug("Model not found for %s.%s", schema, entity)
+		if h.fallbackHandler != nil {
+			logger.Debug("Calling fallback handler for %s.%s", schema, entity)
+			h.fallbackHandler(w, r, params)
+		} else {
+			logger.Debug("No fallback handler set, passing through to next route")
+		}
 		return
 	}
 
-	// Validate that the model is a struct type (not a slice or pointer to slice)
-	modelType := reflect.TypeOf(model)
-	originalType := modelType
-	for modelType != nil && (modelType.Kind() == reflect.Ptr || modelType.Kind() == reflect.Slice || modelType.Kind() == reflect.Array) {
-		modelType = modelType.Elem()
-	}
-
-	if modelType == nil || modelType.Kind() != reflect.Struct {
-		logger.Error("Model for %s.%s must be a struct type, got %v. Please register models as struct types, not slices or pointers to slices.", schema, entity, originalType)
-		h.sendError(w, http.StatusInternalServerError, "invalid_model_type",
-			fmt.Sprintf("Model must be a struct type, got %v. Ensure you register the struct (e.g., ModelCoreAccount{}) not a slice (e.g., []*ModelCoreAccount)", originalType),
-			fmt.Errorf("invalid model type: %v", originalType))
+	// Validate and unwrap model using common utility
+	result, err := common.ValidateAndUnwrapModel(model)
+	if err != nil {
+		logger.Error("Model for %s.%s validation failed: %v", schema, entity, err)
+		h.sendError(w, http.StatusInternalServerError, "invalid_model_type", err.Error(), err)
 		return
 	}
 
-	// If the registered model was a pointer or slice, use the unwrapped struct type
-	if originalType != modelType {
-		model = reflect.New(modelType).Elem().Interface()
-	}
-
-	// Create a pointer to the model type for database operations
-	modelPtr := reflect.New(reflect.TypeOf(model)).Interface()
+	model = result.Model
+	modelPtr := result.ModelPtr
 	tableName := h.getTableName(schema, entity, model)
 
 	// Add request-scoped data to context
@@ -118,6 +146,8 @@ func (h *Handler) Handle(w common.ResponseWriter, r common.Request, params map[s
 		h.handleUpdate(ctx, w, id, req.ID, req.Data, req.Options)
 	case "delete":
 		h.handleDelete(ctx, w, id, req.Data)
+	case "meta":
+		h.handleMeta(ctx, w, schema, entity, model)
 	default:
 		logger.Error("Invalid operation: %s", req.Operation)
 		h.sendError(w, http.StatusBadRequest, "invalid_operation", "Invalid operation", nil)
@@ -133,6 +163,12 @@ func (h *Handler) HandleGet(w common.ResponseWriter, r common.Request, params ma
 		}
 	}()
 
+	// Check for ?openapi query parameter
+	if r.UnderlyingRequest().URL.Query().Get("openapi") != "" {
+		h.HandleOpenAPI(w, r)
+		return
+	}
+
 	schema := params["schema"]
 	entity := params["entity"]
 
@@ -140,8 +176,14 @@ func (h *Handler) HandleGet(w common.ResponseWriter, r common.Request, params ma
 
 	model, err := h.registry.GetModelByEntity(schema, entity)
 	if err != nil {
-		logger.Error("Failed to get model: %v", err)
-		h.sendError(w, http.StatusBadRequest, "invalid_entity", "Invalid entity", err)
+		// Model not found - call fallback handler if set, otherwise pass through
+		logger.Debug("Model not found for %s.%s", schema, entity)
+		if h.fallbackHandler != nil {
+			logger.Debug("Calling fallback handler for %s.%s", schema, entity)
+			h.fallbackHandler(w, r, params)
+		} else {
+			logger.Debug("No fallback handler set, passing through to next route")
+		}
 		return
 	}
 
@@ -149,6 +191,21 @@ func (h *Handler) HandleGet(w common.ResponseWriter, r common.Request, params ma
 	h.sendResponse(w, metadata, nil)
 }
 
+// handleMeta processes meta operation requests
+func (h *Handler) handleMeta(ctx context.Context, w common.ResponseWriter, schema, entity string, model interface{}) {
+	// Capture panics and return error response
+	defer func() {
+		if err := recover(); err != nil {
+			h.handlePanic(w, "handleMeta", err)
+		}
+	}()
+
+	logger.Info("Getting metadata for %s.%s via meta operation", schema, entity)
+
+	metadata := h.generateMetadata(schema, entity, model)
+	h.sendResponse(w, metadata, nil)
+}
+
 func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id string, options common.RequestOptions) {
 	// Capture panics and return error response
 	defer func() {
@@ -191,10 +248,17 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 		query = query.Table(tableName)
 	}
 
+	if len(options.Columns) == 0 && (len(options.ComputedColumns) > 0) {
+		logger.Debug("Populating options.Columns with all model columns since computed columns are additions")
+		options.Columns = reflection.GetSQLModelColumns(model)
+	}
+
 	// Apply column selection
 	if len(options.Columns) > 0 {
 		logger.Debug("Selecting columns: %v", options.Columns)
-		query = query.Column(options.Columns...)
+		for _, col := range options.Columns {
+			query = query.Column(reflection.ExtractSourceColumn(col))
+		}
 	}
 
 	if len(options.ComputedColumns) > 0 {
@@ -206,7 +270,13 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 
 	// Apply preloading
 	if len(options.Preload) > 0 {
-		query = h.applyPreloads(model, query, options.Preload)
+		var err error
+		query, err = h.applyPreloads(model, query, options.Preload)
+		if err != nil {
+			logger.Error("Failed to apply preloads: %v", err)
+			h.sendError(w, http.StatusBadRequest, "invalid_preload", "Failed to apply preloads", err)
+			return
+		}
 	}
 
 	// Apply filters
@@ -225,14 +295,91 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 		query = query.Order(fmt.Sprintf("%s %s", sort.Column, direction))
 	}
 
-	// Get total count before pagination
-	total, err := query.Count(ctx)
-	if err != nil {
-		logger.Error("Error counting records: %v", err)
-		h.sendError(w, http.StatusInternalServerError, "query_error", "Error counting records", err)
-		return
+	// Apply cursor-based pagination
+	if len(options.CursorForward) > 0 || len(options.CursorBackward) > 0 {
+		logger.Debug("Applying cursor pagination")
+
+		// Get primary key name
+		pkName := reflection.GetPrimaryKeyName(model)
+
+		// Extract model columns for validation
+		modelColumns := reflection.GetModelColumns(model)
+
+		// Get cursor filter SQL
+		cursorFilter, err := GetCursorFilter(tableName, pkName, modelColumns, options)
+		if err != nil {
+			logger.Error("Error building cursor filter: %v", err)
+			h.sendError(w, http.StatusBadRequest, "cursor_error", "Invalid cursor pagination", err)
+			return
+		}
+
+		// Apply cursor filter to query
+		if cursorFilter != "" {
+			logger.Debug("Applying cursor filter: %s", cursorFilter)
+			sanitizedCursor := common.SanitizeWhereClause(cursorFilter, reflection.ExtractTableNameOnly(tableName), &options)
+			if sanitizedCursor != "" {
+				query = query.Where(sanitizedCursor)
+			}
+		}
+	}
+
+	// Get total count before pagination
+	var total int
+
+	// Try to get from cache first
+	// Use extended cache key if cursors are present
+	var cacheKeyHash string
+	if len(options.CursorForward) > 0 || len(options.CursorBackward) > 0 {
+		cacheKeyHash = cache.BuildExtendedQueryCacheKey(
+			tableName,
+			options.Filters,
+			options.Sort,
+			"",    // No custom SQL WHERE in resolvespec
+			"",    // No custom SQL OR in resolvespec
+			nil,   // No expand options in resolvespec
+			false, // distinct not used here
+			options.CursorForward,
+			options.CursorBackward,
+		)
+	} else {
+		cacheKeyHash = cache.BuildQueryCacheKey(
+			tableName,
+			options.Filters,
+			options.Sort,
+			"", // No custom SQL WHERE in resolvespec
+			"", // No custom SQL OR in resolvespec
+		)
+	}
+	cacheKey := cache.GetQueryTotalCacheKey(cacheKeyHash)
+
+	// Try to retrieve from cache
+	var cachedTotal cache.CachedTotal
+	err := cache.GetDefaultCache().Get(ctx, cacheKey, &cachedTotal)
+	if err == nil {
+		total = cachedTotal.Total
+		logger.Debug("Total records (from cache): %d", total)
+	} else {
+		// Cache miss - execute count query
+		logger.Debug("Cache miss for query total")
+		count, err := query.Count(ctx)
+		if err != nil {
+			logger.Error("Error counting records: %v", err)
+			h.sendError(w, http.StatusInternalServerError, "query_error", "Error counting records", err)
+			return
+		}
+		total = count
+		logger.Debug("Total records (from query): %d", total)
+
+		// Store in cache
+		cacheTTL := time.Minute * 2 // Default 2 minutes TTL
+		cacheData := cache.CachedTotal{Total: total}
+		if err := cache.GetDefaultCache().Set(ctx, cacheKey, cacheData, cacheTTL); err != nil {
+			logger.Warn("Failed to cache query total: %v", err)
+			// Don't fail the request if caching fails
+		} else {
+			logger.Debug("Cached query total with key: %s", cacheKey)
+		}
 	}
-	logger.Debug("Total records before filtering: %d", total)
 
 	// Apply pagination
 	if options.Limit != nil && *options.Limit > 0 {
@@ -1105,7 +1252,7 @@ type relationshipInfo struct {
 	relatedModel interface{}
 }
 
-func (h *Handler) applyPreloads(model interface{}, query common.SelectQuery, preloads []common.PreloadOption) common.SelectQuery {
+func (h *Handler) applyPreloads(model interface{}, query common.SelectQuery, preloads []common.PreloadOption) (common.SelectQuery, error) {
 	modelType := reflect.TypeOf(model)
 
 	// Unwrap pointers, slices, and arrays to get to the base struct type
@@ -1116,7 +1263,7 @@ func (h *Handler) applyPreloads(model interface{}, query common.SelectQuery, pre
 	// Validate that we have a struct type
 	if modelType == nil || modelType.Kind() != reflect.Struct {
 		logger.Warn("Cannot apply preloads to non-struct type: %v", modelType)
-		return query
+		return query, nil
 	}
 
 	for idx := range preloads {
@@ -1132,15 +1279,25 @@ func (h *Handler) applyPreloads(model interface{}, query common.SelectQuery, pre
 		// ORMs like GORM and Bun expect the struct field name, not the JSON name
 		relationFieldName := relInfo.fieldName
 
-		// For now, we'll preload without conditions
-		// TODO: Implement column selection and filtering for preloads
-		// This requires a more sophisticated approach with callbacks or query builders
-		// Apply preloading
+		// Validate and fix WHERE clause to ensure it contains the relation prefix
+		if len(preload.Where) > 0 {
+			fixedWhere, err := common.ValidateAndFixPreloadWhere(preload.Where, relationFieldName)
+			if err != nil {
+				logger.Error("Invalid preload WHERE clause for relation '%s': %v", relationFieldName, err)
+				return query, fmt.Errorf("invalid preload WHERE clause for relation '%s': %w", relationFieldName, err)
+			}
+			preload.Where = fixedWhere
+		}
 
 		logger.Debug("Applying preload: %s", relationFieldName)
 		query = query.PreloadRelation(relationFieldName, func(sq common.SelectQuery) common.SelectQuery {
+			if len(preload.Columns) == 0 && (len(preload.ComputedQL) > 0 || len(preload.OmitColumns) > 0) {
+				preload.Columns = reflection.GetSQLModelColumns(model)
+			}
+
+			// Handle column selection and omission
 			if len(preload.OmitColumns) > 0 {
-				allCols := reflection.GetModelColumns(model)
+				allCols := reflection.GetSQLModelColumns(model)
 				// Remove omitted columns
 				preload.Columns = []string{}
 				for _, col := range allCols {
@@ -1194,7 +1351,12 @@ func (h *Handler) applyPreloads(model interface{}, query common.SelectQuery, pre
 			}
 
 			if len(preload.Where) > 0 {
-				sq = sq.Where(preload.Where)
+				// Build RequestOptions with all preloads to allow references to sibling relations
+				preloadOpts := &common.RequestOptions{Preload: preloads}
+				sanitizedWhere := common.SanitizeWhereClause(preload.Where, reflection.ExtractTableNameOnly(preload.Relation), preloadOpts)
+				if len(sanitizedWhere) > 0 {
+					sq = sq.Where(sanitizedWhere)
+				}
 			}
 
 			if preload.Limit != nil && *preload.Limit > 0 {
@@ -1207,7 +1369,7 @@ func (h *Handler) applyPreloads(model interface{}, query common.SelectQuery, pre
 		logger.Debug("Applied Preload for relation: %s (field: %s)", preload.Relation, relationFieldName)
 	}
 
-	return query
+	return query, nil
 }
 
 func (h *Handler) getRelationshipInfo(modelType reflect.Type, relationName string) *relationshipInfo {
@@ -1286,3 +1448,31 @@ func toSnakeCase(s string) string {
 	}
 	return strings.ToLower(result.String())
 }
+
+// HandleOpenAPI generates and returns the OpenAPI specification
+func (h *Handler) HandleOpenAPI(w common.ResponseWriter, r common.Request) {
+	if h.openAPIGenerator == nil {
+		logger.Error("OpenAPI generator not configured")
+		h.sendError(w, http.StatusInternalServerError, "openapi_not_configured", "OpenAPI generation not configured", nil)
+		return
+	}
+
+	spec, err := h.openAPIGenerator()
+	if err != nil {
+		logger.Error("Failed to generate OpenAPI spec: %v", err)
+		h.sendError(w, http.StatusInternalServerError, "openapi_generation_error", "Failed to generate OpenAPI specification", err)
+		return
+	}
+
+	w.SetHeader("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	_, err = w.Write([]byte(spec))
+	if err != nil {
+		logger.Error("Error sending OpenAPI spec response: %v", err)
+	}
+}
+
+// SetOpenAPIGenerator sets the OpenAPI generator function
+func (h *Handler) SetOpenAPIGenerator(generator func() (string, error)) {
+	h.openAPIGenerator = generator
+}

pkg/resolvespec/handler_test.go

@@ -0,0 +1,367 @@
+package resolvespec
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+)
+
+func TestNewHandler(t *testing.T) {
+	// Note: We can't create a real handler without actual DB and registry
+	// But we can test that the constructor doesn't panic with nil values
+	handler := NewHandler(nil, nil)
+	if handler == nil {
+		t.Error("Expected handler to be created, got nil")
+	}
+
+	if handler.hooks == nil {
+		t.Error("Expected hooks registry to be initialized")
+	}
+}
+
+func TestHandlerHooks(t *testing.T) {
+	handler := NewHandler(nil, nil)
+	hooks := handler.Hooks()
+	if hooks == nil {
+		t.Error("Expected hooks registry, got nil")
+	}
+}
+
+func TestSetFallbackHandler(t *testing.T) {
+	handler := NewHandler(nil, nil)
+
+	// We can't directly call the fallback without mocks, but we can verify it's set
+	handler.SetFallbackHandler(func(w common.ResponseWriter, r common.Request, params map[string]string) {
+		// Fallback handler implementation
+	})
+
+	if handler.fallbackHandler == nil {
+		t.Error("Expected fallback handler to be set")
+	}
+}
+
+func TestGetDatabase(t *testing.T) {
+	handler := NewHandler(nil, nil)
+	db := handler.GetDatabase()
+	// Should return nil since we passed nil
+	if db != nil {
+		t.Error("Expected nil database")
+	}
+}
+
+func TestParseTableName(t *testing.T) {
+	handler := NewHandler(nil, nil)
+
+	tests := []struct {
+		name           string
+		fullTableName  string
+		expectedSchema string
+		expectedTable  string
+	}{
+		{
+			name:           "Table with schema",
+			fullTableName:  "public.users",
+			expectedSchema: "public",
+			expectedTable:  "users",
+		},
+		{
+			name:           "Table without schema",
+			fullTableName:  "users",
+			expectedSchema: "",
+			expectedTable:  "users",
+		},
+		{
+			name:           "Multiple dots (use last)",
+			fullTableName:  "db.public.users",
+			expectedSchema: "db.public",
+			expectedTable:  "users",
+		},
+		{
+			name:           "Empty string",
+			fullTableName:  "",
+			expectedSchema: "",
+			expectedTable:  "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			schema, table := handler.parseTableName(tt.fullTableName)
+			if schema != tt.expectedSchema {
+				t.Errorf("Expected schema '%s', got '%s'", tt.expectedSchema, schema)
+			}
+			if table != tt.expectedTable {
+				t.Errorf("Expected table '%s', got '%s'", tt.expectedTable, table)
+			}
+		})
+	}
+}
+
+func TestGetColumnType(t *testing.T) {
+	tests := []struct {
+		name         string
+		field        reflect.StructField
+		expectedType string
+	}{
+		{
+			name: "String field",
+			field: reflect.StructField{
+				Name: "Name",
+				Type: reflect.TypeOf(""),
+			},
+			expectedType: "string",
+		},
+		{
+			name: "Int field",
+			field: reflect.StructField{
+				Name: "Count",
+				Type: reflect.TypeOf(int(0)),
+			},
+			expectedType: "integer",
+		},
+		{
+			name: "Int32 field",
+			field: reflect.StructField{
+				Name: "ID",
+				Type: reflect.TypeOf(int32(0)),
+			},
+			expectedType: "integer",
+		},
+		{
+			name: "Int64 field",
+			field: reflect.StructField{
+				Name: "BigID",
+				Type: reflect.TypeOf(int64(0)),
+			},
+			expectedType: "bigint",
+		},
+		{
+			name: "Float32 field",
+			field: reflect.StructField{
+				Name: "Price",
+				Type: reflect.TypeOf(float32(0)),
+			},
+			expectedType: "float",
+		},
+		{
+			name: "Float64 field",
+			field: reflect.StructField{
+				Name: "Amount",
+				Type: reflect.TypeOf(float64(0)),
+			},
+			expectedType: "double",
+		},
+		{
+			name: "Bool field",
+			field: reflect.StructField{
+				Name: "Active",
+				Type: reflect.TypeOf(false),
+			},
+			expectedType: "boolean",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			colType := getColumnType(tt.field)
+			if colType != tt.expectedType {
+				t.Errorf("Expected column type '%s', got '%s'", tt.expectedType, colType)
+			}
+		})
+	}
+}
+
+func TestIsNullable(t *testing.T) {
+	tests := []struct {
+		name     string
+		field    reflect.StructField
+		nullable bool
+	}{
+		{
+			name: "Pointer type is nullable",
+			field: reflect.StructField{
+				Name: "Name",
+				Type: reflect.TypeOf((*string)(nil)),
+			},
+			nullable: true,
+		},
+		{
+			name: "Non-pointer type without explicit 'not null' tag",
+			field: reflect.StructField{
+				Name: "ID",
+				Type: reflect.TypeOf(int(0)),
+			},
+			nullable: true, // isNullable returns true if there's no explicit "not null" tag
+		},
+		{
+			name: "Field with 'not null' tag is not nullable",
+			field: reflect.StructField{
+				Name: "Email",
+				Type: reflect.TypeOf(""),
+				Tag:  `gorm:"not null"`,
+			},
+			nullable: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := isNullable(tt.field)
+			if result != tt.nullable {
+				t.Errorf("Expected nullable=%v, got %v", tt.nullable, result)
+			}
+		})
+	}
+}
+
+func TestToSnakeCase(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		{
+			input:    "UserID",
+			expected: "user_id",
+		},
+		{
+			input:    "DepartmentName",
+			expected: "department_name",
+		},
+		{
+			input:    "ID",
+			expected: "id",
+		},
+		{
+			input:    "HTTPServer",
+			expected: "http_server",
+		},
+		{
+			input:    "createdAt",
+			expected: "created_at",
+		},
+		{
+			input:    "name",
+			expected: "name",
+		},
+		{
+			input:    "",
+			expected: "",
+		},
+		{
+			input:    "A",
+			expected: "a",
+		},
+		{
+			input:    "APIKey",
+			expected: "api_key",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			result := toSnakeCase(tt.input)
+			if result != tt.expected {
+				t.Errorf("toSnakeCase(%q) = %q, expected %q", tt.input, result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestExtractTagValue(t *testing.T) {
+	handler := NewHandler(nil, nil)
+
+	tests := []struct {
+		name     string
+		tag      string
+		key      string
+		expected string
+	}{
+		{
+			name:     "Extract foreignKey",
+			tag:      "foreignKey:UserID;references:ID",
+			key:      "foreignKey",
+			expected: "UserID",
+		},
+		{
+			name:     "Extract references",
+			tag:      "foreignKey:UserID;references:ID",
+			key:      "references",
+			expected: "ID",
+		},
+		{
+			name:     "Key not found",
+			tag:      "foreignKey:UserID;references:ID",
+			key:      "notfound",
+			expected: "",
+		},
+		{
+			name:     "Empty tag",
+			tag:      "",
+			key:      "foreignKey",
+			expected: "",
+		},
+		{
+			name:     "Single value",
+			tag:      "many2many:user_roles",
+			key:      "many2many",
+			expected: "user_roles",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := handler.extractTagValue(tt.tag, tt.key)
+			if result != tt.expected {
+				t.Errorf("extractTagValue(%q, %q) = %q, expected %q", tt.tag, tt.key, result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestApplyFilter(t *testing.T) {
+	// Note: Without a real database, we can't fully test query execution
+	// But we can test that the method exists
+	_ = NewHandler(nil, nil)
+
+	// The applyFilter method exists and can be tested with actual queries
+	// but requires database setup which is beyond unit test scope
+	t.Log("applyFilter method exists and is used in handler operations")
+}
+
+func TestShouldUseNestedProcessor(t *testing.T) {
+	handler := NewHandler(nil, nil)
+
+	tests := []struct {
+		name     string
+		data     map[string]interface{}
+		expected bool
+	}{
+		{
+			name: "Has _request field",
+			data: map[string]interface{}{
+				"_request": "nested",
+				"name":     "test",
+			},
+			expected: true,
+		},
+		{
+			name: "No special fields",
+			data: map[string]interface{}{
+				"name":  "test",
+				"email": "test@example.com",
+			},
+			expected: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Note: Without a real model, we can't fully test this
+			// But we can verify the function exists
+			result := handler.shouldUseNestedProcessor(tt.data, nil)
+			// The actual result depends on the model structure
+			_ = result
+		})
+	}
+}

pkg/resolvespec/hooks.go

@@ -0,0 +1,152 @@
+package resolvespec
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
+)
+
+// HookType defines the type of hook to execute
+type HookType string
+
+const (
+	// Read operation hooks
+	BeforeRead HookType = "before_read"
+	AfterRead  HookType = "after_read"
+
+	// Create operation hooks
+	BeforeCreate HookType = "before_create"
+	AfterCreate  HookType = "after_create"
+
+	// Update operation hooks
+	BeforeUpdate HookType = "before_update"
+	AfterUpdate  HookType = "after_update"
+
+	// Delete operation hooks
+	BeforeDelete HookType = "before_delete"
+	AfterDelete  HookType = "after_delete"
+
+	// Scan/Execute operation hooks (for query building)
+	BeforeScan HookType = "before_scan"
+)
+
+// HookContext contains all the data available to a hook
+type HookContext struct {
+	Context context.Context
+	Handler *Handler // Reference to the handler for accessing database, registry, etc.
+	Schema  string
+	Entity  string
+	Model   interface{}
+	Options common.RequestOptions
+	Writer  common.ResponseWriter
+	Request common.Request
+
+	// Operation-specific fields
+	ID     string
+	Data   interface{} // For create/update operations
+	Result interface{} // For after hooks
+	Error  error       // For after hooks
+
+	// Query chain - allows hooks to modify the query before execution
+	Query common.SelectQuery
+
+	// Allow hooks to abort the operation
+	Abort        bool   // If set to true, the operation will be aborted
+	AbortMessage string // Message to return if aborted
+	AbortCode    int    // HTTP status code if aborted
+}
+
+// HookFunc is the signature for hook functions
+// It receives a HookContext and can modify it or return an error
+// If an error is returned, the operation will be aborted
+type HookFunc func(*HookContext) error
+
+// HookRegistry manages all registered hooks
+type HookRegistry struct {
+	hooks map[HookType][]HookFunc
+}
+
+// NewHookRegistry creates a new hook registry
+func NewHookRegistry() *HookRegistry {
+	return &HookRegistry{
+		hooks: make(map[HookType][]HookFunc),
+	}
+}
+
+// Register adds a new hook for the specified hook type
+func (r *HookRegistry) Register(hookType HookType, hook HookFunc) {
+	if r.hooks == nil {
+		r.hooks = make(map[HookType][]HookFunc)
+	}
+	r.hooks[hookType] = append(r.hooks[hookType], hook)
+	logger.Info("Registered resolvespec hook for %s (total: %d)", hookType, len(r.hooks[hookType]))
+}
+
+// RegisterMultiple registers a hook for multiple hook types
+func (r *HookRegistry) RegisterMultiple(hookTypes []HookType, hook HookFunc) {
+	for _, hookType := range hookTypes {
+		r.Register(hookType, hook)
+	}
+}
+
+// Execute runs all hooks for the specified type in order
+// If any hook returns an error, execution stops and the error is returned
+func (r *HookRegistry) Execute(hookType HookType, ctx *HookContext) error {
+	hooks, exists := r.hooks[hookType]
+	if !exists || len(hooks) == 0 {
+		return nil
+	}
+
+	logger.Debug("Executing %d resolvespec hook(s) for %s", len(hooks), hookType)
+
+	for i, hook := range hooks {
+		if err := hook(ctx); err != nil {
+			logger.Error("Resolvespec hook %d for %s failed: %v", i+1, hookType, err)
+			return fmt.Errorf("hook execution failed: %w", err)
+		}
+
+		// Check if hook requested abort
+		if ctx.Abort {
+			logger.Warn("Resolvespec hook %d for %s requested abort: %s", i+1, hookType, ctx.AbortMessage)
+			return fmt.Errorf("operation aborted by hook: %s", ctx.AbortMessage)
+		}
+	}
+
+	return nil
+}
+
+// Clear removes all hooks for the specified type
+func (r *HookRegistry) Clear(hookType HookType) {
+	delete(r.hooks, hookType)
+	logger.Info("Cleared all resolvespec hooks for %s", hookType)
+}
+
+// ClearAll removes all registered hooks
+func (r *HookRegistry) ClearAll() {
+	r.hooks = make(map[HookType][]HookFunc)
+	logger.Info("Cleared all resolvespec hooks")
+}
+
+// Count returns the number of hooks registered for a specific type
+func (r *HookRegistry) Count(hookType HookType) int {
+	if hooks, exists := r.hooks[hookType]; exists {
+		return len(hooks)
+	}
+	return 0
+}
+
+// HasHooks returns true if there are any hooks registered for the specified type
+func (r *HookRegistry) HasHooks(hookType HookType) bool {
+	return r.Count(hookType) > 0
+}
+
+// GetAllHookTypes returns all hook types that have registered hooks
+func (r *HookRegistry) GetAllHookTypes() []HookType {
+	types := make([]HookType, 0, len(r.hooks))
+	for hookType := range r.hooks {
+		types = append(types, hookType)
+	}
+	return types
+}

pkg/resolvespec/hooks_test.go

@@ -0,0 +1,400 @@
+package resolvespec
+
+import (
+	"context"
+	"fmt"
+	"testing"
+)
+
+func TestHookRegistry(t *testing.T) {
+	registry := NewHookRegistry()
+
+	// Test registering a hook
+	called := false
+	hook := func(ctx *HookContext) error {
+		called = true
+		return nil
+	}
+
+	registry.Register(BeforeRead, hook)
+
+	if registry.Count(BeforeRead) != 1 {
+		t.Errorf("Expected 1 hook, got %d", registry.Count(BeforeRead))
+	}
+
+	// Test executing a hook
+	ctx := &HookContext{
+		Context: context.Background(),
+		Schema:  "test",
+		Entity:  "users",
+	}
+
+	err := registry.Execute(BeforeRead, ctx)
+	if err != nil {
+		t.Errorf("Hook execution failed: %v", err)
+	}
+
+	if !called {
+		t.Error("Hook was not called")
+	}
+}
+
+func TestHookExecutionOrder(t *testing.T) {
+	registry := NewHookRegistry()
+
+	order := []int{}
+
+	hook1 := func(ctx *HookContext) error {
+		order = append(order, 1)
+		return nil
+	}
+
+	hook2 := func(ctx *HookContext) error {
+		order = append(order, 2)
+		return nil
+	}
+
+	hook3 := func(ctx *HookContext) error {
+		order = append(order, 3)
+		return nil
+	}
+
+	registry.Register(BeforeCreate, hook1)
+	registry.Register(BeforeCreate, hook2)
+	registry.Register(BeforeCreate, hook3)
+
+	ctx := &HookContext{
+		Context: context.Background(),
+		Schema:  "test",
+		Entity:  "users",
+	}
+
+	err := registry.Execute(BeforeCreate, ctx)
+	if err != nil {
+		t.Errorf("Hook execution failed: %v", err)
+	}
+
+	if len(order) != 3 {
+		t.Errorf("Expected 3 hooks to be called, got %d", len(order))
+	}
+
+	if order[0] != 1 || order[1] != 2 || order[2] != 3 {
+		t.Errorf("Hooks executed in wrong order: %v", order)
+	}
+}
+
+func TestHookError(t *testing.T) {
+	registry := NewHookRegistry()
+
+	executed := []string{}
+
+	hook1 := func(ctx *HookContext) error {
+		executed = append(executed, "hook1")
+		return nil
+	}
+
+	hook2 := func(ctx *HookContext) error {
+		executed = append(executed, "hook2")
+		return fmt.Errorf("hook2 error")
+	}
+
+	hook3 := func(ctx *HookContext) error {
+		executed = append(executed, "hook3")
+		return nil
+	}
+
+	registry.Register(BeforeUpdate, hook1)
+	registry.Register(BeforeUpdate, hook2)
+	registry.Register(BeforeUpdate, hook3)
+
+	ctx := &HookContext{
+		Context: context.Background(),
+		Schema:  "test",
+		Entity:  "users",
+	}
+
+	err := registry.Execute(BeforeUpdate, ctx)
+	if err == nil {
+		t.Error("Expected error from hook execution")
+	}
+
+	if len(executed) != 2 {
+		t.Errorf("Expected only 2 hooks to be executed, got %d", len(executed))
+	}
+
+	if executed[0] != "hook1" || executed[1] != "hook2" {
+		t.Errorf("Unexpected execution order: %v", executed)
+	}
+}
+
+func TestHookDataModification(t *testing.T) {
+	registry := NewHookRegistry()
+
+	modifyHook := func(ctx *HookContext) error {
+		if dataMap, ok := ctx.Data.(map[string]interface{}); ok {
+			dataMap["modified"] = true
+			ctx.Data = dataMap
+		}
+		return nil
+	}
+
+	registry.Register(BeforeCreate, modifyHook)
+
+	data := map[string]interface{}{
+		"name": "test",
+	}
+
+	ctx := &HookContext{
+		Context: context.Background(),
+		Schema:  "test",
+		Entity:  "users",
+		Data:    data,
+	}
+
+	err := registry.Execute(BeforeCreate, ctx)
+	if err != nil {
+		t.Errorf("Hook execution failed: %v", err)
+	}
+
+	modifiedData := ctx.Data.(map[string]interface{})
+	if !modifiedData["modified"].(bool) {
+		t.Error("Data was not modified by hook")
+	}
+}
+
+func TestRegisterMultiple(t *testing.T) {
+	registry := NewHookRegistry()
+
+	called := 0
+	hook := func(ctx *HookContext) error {
+		called++
+		return nil
+	}
+
+	registry.RegisterMultiple([]HookType{
+		BeforeRead,
+		BeforeCreate,
+		BeforeUpdate,
+	}, hook)
+
+	if registry.Count(BeforeRead) != 1 {
+		t.Error("Hook not registered for BeforeRead")
+	}
+	if registry.Count(BeforeCreate) != 1 {
+		t.Error("Hook not registered for BeforeCreate")
+	}
+	if registry.Count(BeforeUpdate) != 1 {
+		t.Error("Hook not registered for BeforeUpdate")
+	}
+
+	ctx := &HookContext{
+		Context: context.Background(),
+		Schema:  "test",
+		Entity:  "users",
+	}
+
+	registry.Execute(BeforeRead, ctx)
+	registry.Execute(BeforeCreate, ctx)
+	registry.Execute(BeforeUpdate, ctx)
+
+	if called != 3 {
+		t.Errorf("Expected hook to be called 3 times, got %d", called)
+	}
+}
+
+func TestClearHooks(t *testing.T) {
+	registry := NewHookRegistry()
+
+	hook := func(ctx *HookContext) error {
+		return nil
+	}
+
+	registry.Register(BeforeRead, hook)
+	registry.Register(BeforeCreate, hook)
+
+	if registry.Count(BeforeRead) != 1 {
+		t.Error("Hook not registered")
+	}
+
+	registry.Clear(BeforeRead)
+
+	if registry.Count(BeforeRead) != 0 {
+		t.Error("Hook not cleared")
+	}
+
+	if registry.Count(BeforeCreate) != 1 {
+		t.Error("Wrong hook was cleared")
+	}
+}
+
+func TestClearAllHooks(t *testing.T) {
+	registry := NewHookRegistry()
+
+	hook := func(ctx *HookContext) error {
+		return nil
+	}
+
+	registry.Register(BeforeRead, hook)
+	registry.Register(BeforeCreate, hook)
+	registry.Register(BeforeUpdate, hook)
+
+	registry.ClearAll()
+
+	if registry.Count(BeforeRead) != 0 || registry.Count(BeforeCreate) != 0 || registry.Count(BeforeUpdate) != 0 {
+		t.Error("Not all hooks were cleared")
+	}
+}
+
+func TestHasHooks(t *testing.T) {
+	registry := NewHookRegistry()
+
+	if registry.HasHooks(BeforeRead) {
+		t.Error("Should not have hooks initially")
+	}
+
+	hook := func(ctx *HookContext) error {
+		return nil
+	}
+
+	registry.Register(BeforeRead, hook)
+
+	if !registry.HasHooks(BeforeRead) {
+		t.Error("Should have hooks after registration")
+	}
+}
+
+func TestGetAllHookTypes(t *testing.T) {
+	registry := NewHookRegistry()
+
+	hook := func(ctx *HookContext) error {
+		return nil
+	}
+
+	registry.Register(BeforeRead, hook)
+	registry.Register(BeforeCreate, hook)
+	registry.Register(AfterUpdate, hook)
+
+	types := registry.GetAllHookTypes()
+
+	if len(types) != 3 {
+		t.Errorf("Expected 3 hook types, got %d", len(types))
+	}
+
+	// Verify all expected types are present
+	expectedTypes := map[HookType]bool{
+		BeforeRead:   true,
+		BeforeCreate: true,
+		AfterUpdate:  true,
+	}
+
+	for _, hookType := range types {
+		if !expectedTypes[hookType] {
+			t.Errorf("Unexpected hook type: %s", hookType)
+		}
+	}
+}
+
+func TestHookContextHandler(t *testing.T) {
+	registry := NewHookRegistry()
+
+	var capturedHandler *Handler
+
+	hook := func(ctx *HookContext) error {
+		if ctx.Handler == nil {
+			return fmt.Errorf("handler is nil in hook context")
+		}
+		capturedHandler = ctx.Handler
+		return nil
+	}
+
+	registry.Register(BeforeRead, hook)
+
+	handler := &Handler{
+		hooks: registry,
+	}
+
+	ctx := &HookContext{
+		Context: context.Background(),
+		Handler: handler,
+		Schema:  "test",
+		Entity:  "users",
+	}
+
+	err := registry.Execute(BeforeRead, ctx)
+	if err != nil {
+		t.Errorf("Hook execution failed: %v", err)
+	}
+
+	if capturedHandler == nil {
+		t.Error("Handler was not captured from hook context")
+	}
+
+	if capturedHandler != handler {
+		t.Error("Captured handler does not match original handler")
+	}
+}
+
+func TestHookAbort(t *testing.T) {
+	registry := NewHookRegistry()
+
+	abortHook := func(ctx *HookContext) error {
+		ctx.Abort = true
+		ctx.AbortMessage = "Operation aborted by hook"
+		ctx.AbortCode = 403
+		return nil
+	}
+
+	registry.Register(BeforeCreate, abortHook)
+
+	ctx := &HookContext{
+		Context: context.Background(),
+		Schema:  "test",
+		Entity:  "users",
+	}
+
+	err := registry.Execute(BeforeCreate, ctx)
+	if err == nil {
+		t.Error("Expected error when hook sets Abort=true")
+	}
+
+	if err.Error() != "operation aborted by hook: Operation aborted by hook" {
+		t.Errorf("Expected abort error message, got: %v", err)
+	}
+}
+
+func TestHookTypes(t *testing.T) {
+	// Test all hook type constants
+	hookTypes := []HookType{
+		BeforeRead,
+		AfterRead,
+		BeforeCreate,
+		AfterCreate,
+		BeforeUpdate,
+		AfterUpdate,
+		BeforeDelete,
+		AfterDelete,
+		BeforeScan,
+	}
+
+	for _, hookType := range hookTypes {
+		if string(hookType) == "" {
+			t.Errorf("Hook type should not be empty: %v", hookType)
+		}
+	}
+}
+
+func TestExecuteWithNoHooks(t *testing.T) {
+	registry := NewHookRegistry()
+
+	ctx := &HookContext{
+		Context: context.Background(),
+		Schema:  "test",
+		Entity:  "users",
+	}
+
+	// Executing with no registered hooks should not cause an error
+	err := registry.Execute(BeforeRead, ctx)
+	if err != nil {
+		t.Errorf("Execute should not fail with no hooks, got: %v", err)
+	}
+}

pkg/resolvespec/integration_test.go

@@ -0,0 +1,508 @@
+// +build integration
+
+package resolvespec
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/gorilla/mux"
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+	"gorm.io/gorm/logger"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+)
+
+// Test models
+type TestUser struct {
+	ID        uint      `gorm:"primaryKey" json:"id"`
+	Name      string    `gorm:"not null" json:"name"`
+	Email     string    `gorm:"uniqueIndex;not null" json:"email"`
+	Age       int       `json:"age"`
+	Active    bool      `gorm:"default:true" json:"active"`
+	CreatedAt time.Time `json:"created_at"`
+	Posts     []TestPost `gorm:"foreignKey:UserID" json:"posts,omitempty"`
+}
+
+func (TestUser) TableName() string {
+	return "test_users"
+}
+
+type TestPost struct {
+	ID        uint      `gorm:"primaryKey" json:"id"`
+	UserID    uint      `gorm:"not null" json:"user_id"`
+	Title     string    `gorm:"not null" json:"title"`
+	Content   string    `json:"content"`
+	Published bool      `gorm:"default:false" json:"published"`
+	CreatedAt time.Time `json:"created_at"`
+	User      *TestUser  `gorm:"foreignKey:UserID" json:"user,omitempty"`
+	Comments  []TestComment `gorm:"foreignKey:PostID" json:"comments,omitempty"`
+}
+
+func (TestPost) TableName() string {
+	return "test_posts"
+}
+
+type TestComment struct {
+	ID        uint      `gorm:"primaryKey" json:"id"`
+	PostID    uint      `gorm:"not null" json:"post_id"`
+	Content   string    `gorm:"not null" json:"content"`
+	CreatedAt time.Time `json:"created_at"`
+	Post      *TestPost  `gorm:"foreignKey:PostID" json:"post,omitempty"`
+}
+
+func (TestComment) TableName() string {
+	return "test_comments"
+}
+
+// Test helper functions
+func setupTestDB(t *testing.T) *gorm.DB {
+	// Get connection string from environment or use default
+	dsn := os.Getenv("TEST_DATABASE_URL")
+	if dsn == "" {
+		dsn = "host=localhost user=postgres password=postgres dbname=resolvespec_test port=5434 sslmode=disable"
+	}
+
+	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{
+		Logger: logger.Default.LogMode(logger.Silent),
+	})
+	if err != nil {
+		t.Skipf("Skipping integration test: database not available: %v", err)
+		return nil
+	}
+
+	// Run migrations
+	err = db.AutoMigrate(&TestUser{}, &TestPost{}, &TestComment{})
+	if err != nil {
+		t.Skipf("Skipping integration test: failed to migrate database: %v", err)
+		return nil
+	}
+
+	return db
+}
+
+func cleanupTestDB(t *testing.T, db *gorm.DB) {
+	// Clean up test data
+	db.Exec("TRUNCATE TABLE test_comments CASCADE")
+	db.Exec("TRUNCATE TABLE test_posts CASCADE")
+	db.Exec("TRUNCATE TABLE test_users CASCADE")
+}
+
+func createTestData(t *testing.T, db *gorm.DB) {
+	users := []TestUser{
+		{Name: "John Doe", Email: "john@example.com", Age: 30, Active: true},
+		{Name: "Jane Smith", Email: "jane@example.com", Age: 25, Active: true},
+		{Name: "Bob Johnson", Email: "bob@example.com", Age: 35, Active: false},
+	}
+
+	for i := range users {
+		if err := db.Create(&users[i]).Error; err != nil {
+			t.Fatalf("Failed to create test user: %v", err)
+		}
+	}
+
+	posts := []TestPost{
+		{UserID: users[0].ID, Title: "First Post", Content: "Hello World", Published: true},
+		{UserID: users[0].ID, Title: "Second Post", Content: "More content", Published: true},
+		{UserID: users[1].ID, Title: "Jane's Post", Content: "Jane's content", Published: false},
+	}
+
+	for i := range posts {
+		if err := db.Create(&posts[i]).Error; err != nil {
+			t.Fatalf("Failed to create test post: %v", err)
+		}
+	}
+
+	comments := []TestComment{
+		{PostID: posts[0].ID, Content: "Great post!"},
+		{PostID: posts[0].ID, Content: "Thanks for sharing"},
+		{PostID: posts[1].ID, Content: "Interesting"},
+	}
+
+	for i := range comments {
+		if err := db.Create(&comments[i]).Error; err != nil {
+			t.Fatalf("Failed to create test comment: %v", err)
+		}
+	}
+}
+
+// Integration tests
+func TestIntegration_CreateOperation(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.RegisterModel("public", "test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Create a new user
+	requestBody := map[string]interface{}{
+		"operation": "create",
+		"data": map[string]interface{}{
+			"name":  "Test User",
+			"email": "test@example.com",
+			"age":   28,
+		},
+	}
+
+	body, _ := json.Marshal(requestBody)
+	req := httptest.NewRequest("POST", "/public/test_users", bytes.NewBuffer(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v. Error: %v", response.Success, response.Error)
+	}
+
+	// Verify user was created
+	var user TestUser
+	if err := db.Where("email = ?", "test@example.com").First(&user).Error; err != nil {
+		t.Errorf("Failed to find created user: %v", err)
+	}
+
+	if user.Name != "Test User" {
+		t.Errorf("Expected name 'Test User', got '%s'", user.Name)
+	}
+}
+
+func TestIntegration_ReadOperation(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.RegisterModel("public", "test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Read all users
+	requestBody := map[string]interface{}{
+		"operation": "read",
+		"options": map[string]interface{}{
+			"limit": 10,
+		},
+	}
+
+	body, _ := json.Marshal(requestBody)
+	req := httptest.NewRequest("POST", "/public/test_users", bytes.NewBuffer(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	if response.Metadata == nil {
+		t.Fatal("Expected metadata, got nil")
+	}
+
+	if response.Metadata.Total != 3 {
+		t.Errorf("Expected 3 users, got %d", response.Metadata.Total)
+	}
+}
+
+func TestIntegration_ReadWithFilters(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.RegisterModel("public", "test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Read users with age > 25
+	requestBody := map[string]interface{}{
+		"operation": "read",
+		"options": map[string]interface{}{
+			"filters": []map[string]interface{}{
+				{
+					"column":   "age",
+					"operator": "gt",
+					"value":    25,
+				},
+			},
+		},
+	}
+
+	body, _ := json.Marshal(requestBody)
+	req := httptest.NewRequest("POST", "/public/test_users", bytes.NewBuffer(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d", w.Code)
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	// Should return 2 users (John: 30, Bob: 35)
+	if response.Metadata.Total != 2 {
+		t.Errorf("Expected 2 filtered users, got %d", response.Metadata.Total)
+	}
+}
+
+func TestIntegration_UpdateOperation(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.RegisterModel("public", "test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Get user ID
+	var user TestUser
+	db.Where("email = ?", "john@example.com").First(&user)
+
+	// Update user
+	requestBody := map[string]interface{}{
+		"operation": "update",
+		"data": map[string]interface{}{
+			"id":   user.ID,
+			"age":  31,
+			"name": "John Doe Updated",
+		},
+	}
+
+	body, _ := json.Marshal(requestBody)
+	req := httptest.NewRequest("POST", fmt.Sprintf("/public/test_users/%d", user.ID), bytes.NewBuffer(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	// Verify update
+	var updatedUser TestUser
+	db.First(&updatedUser, user.ID)
+
+	if updatedUser.Age != 31 {
+		t.Errorf("Expected age 31, got %d", updatedUser.Age)
+	}
+	if updatedUser.Name != "John Doe Updated" {
+		t.Errorf("Expected name 'John Doe Updated', got '%s'", updatedUser.Name)
+	}
+}
+
+func TestIntegration_DeleteOperation(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.RegisterModel("public", "test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Get user ID
+	var user TestUser
+	db.Where("email = ?", "bob@example.com").First(&user)
+
+	// Delete user
+	requestBody := map[string]interface{}{
+		"operation": "delete",
+	}
+
+	body, _ := json.Marshal(requestBody)
+	req := httptest.NewRequest("POST", fmt.Sprintf("/public/test_users/%d", user.ID), bytes.NewBuffer(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	// Verify deletion
+	var count int64
+	db.Model(&TestUser{}).Where("id = ?", user.ID).Count(&count)
+
+	if count != 0 {
+		t.Errorf("Expected user to be deleted, but found %d records", count)
+	}
+}
+
+func TestIntegration_MetadataOperation(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.RegisterModel("public", "test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Get metadata
+	requestBody := map[string]interface{}{
+		"operation": "meta",
+	}
+
+	body, _ := json.Marshal(requestBody)
+	req := httptest.NewRequest("POST", "/public/test_users", bytes.NewBuffer(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	// Check that metadata includes columns
+	// The response.Data is an interface{}, we need to unmarshal it properly
+	dataBytes, _ := json.Marshal(response.Data)
+	var metadata common.TableMetadata
+	if err := json.Unmarshal(dataBytes, &metadata); err != nil {
+		t.Fatalf("Failed to unmarshal metadata: %v. Raw data: %+v", err, response.Data)
+	}
+
+	if len(metadata.Columns) == 0 {
+		t.Error("Expected metadata to contain columns")
+	}
+
+	// Verify some expected columns
+	hasID := false
+	hasName := false
+	hasEmail := false
+	for _, col := range metadata.Columns {
+		if col.Name == "id" {
+			hasID = true
+			if !col.IsPrimary {
+				t.Error("Expected 'id' column to be primary key")
+			}
+		}
+		if col.Name == "name" {
+			hasName = true
+		}
+		if col.Name == "email" {
+			hasEmail = true
+		}
+	}
+
+	if !hasID || !hasName || !hasEmail {
+		t.Error("Expected metadata to contain 'id', 'name', and 'email' columns")
+	}
+}
+
+func TestIntegration_ReadWithPreload(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.RegisterModel("public", "test_users", TestUser{})
+	handler.RegisterModel("public", "test_posts", TestPost{})
+	handler.RegisterModel("public", "test_comments", TestComment{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Read users with posts preloaded
+	requestBody := map[string]interface{}{
+		"operation": "read",
+		"options": map[string]interface{}{
+			"filters": []map[string]interface{}{
+				{
+					"column":   "email",
+					"operator": "eq",
+					"value":    "john@example.com",
+				},
+			},
+			"preload": []map[string]interface{}{
+				{"relation": "posts"},
+			},
+		},
+	}
+
+	body, _ := json.Marshal(requestBody)
+	req := httptest.NewRequest("POST", "/public/test_users", bytes.NewBuffer(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	// Verify posts are preloaded
+	dataBytes, _ := json.Marshal(response.Data)
+	var users []TestUser
+	json.Unmarshal(dataBytes, &users)
+
+	if len(users) == 0 {
+		t.Fatal("Expected at least one user")
+	}
+
+	if len(users[0].Posts) == 0 {
+		t.Error("Expected posts to be preloaded")
+	}
+}

pkg/resolvespec/resolvespec.go

@@ -2,12 +2,14 @@ package resolvespec
 
 import (
 	"net/http"
+	"strings"
 
 	"github.com/gorilla/mux"
 	"github.com/uptrace/bun"
 	"github.com/uptrace/bunrouter"
 	"gorm.io/gorm"
 
+	"github.com/bitechdev/ResolveSpec/pkg/common"
 	"github.com/bitechdev/ResolveSpec/pkg/common/adapters/database"
 	"github.com/bitechdev/ResolveSpec/pkg/common/adapters/router"
 	"github.com/bitechdev/ResolveSpec/pkg/modelregistry"
@@ -37,28 +39,132 @@ func NewStandardBunRouter() *router.StandardBunRouterAdapter {
 	return router.NewStandardBunRouterAdapter()
 }
 
+// MiddlewareFunc is a function that wraps an http.Handler with additional functionality
+type MiddlewareFunc func(http.Handler) http.Handler
+
 // SetupMuxRoutes sets up routes for the ResolveSpec API with Mux
-func SetupMuxRoutes(muxRouter *mux.Router, handler *Handler) {
-	muxRouter.HandleFunc("/{schema}/{entity}", func(w http.ResponseWriter, r *http.Request) {
-		vars := mux.Vars(r)
-		reqAdapter := router.NewHTTPRequest(r)
+// authMiddleware is optional - if provided, routes will be protected with the middleware
+// Example: SetupMuxRoutes(router, handler, func(h http.Handler) http.Handler { return security.NewAuthHandler(securityList, h) })
+func SetupMuxRoutes(muxRouter *mux.Router, handler *Handler, authMiddleware MiddlewareFunc) {
+	// Add global /openapi route
+	openAPIHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		corsConfig := common.DefaultCORSConfig()
 		respAdapter := router.NewHTTPResponseWriter(w)
-		handler.Handle(respAdapter, reqAdapter, vars)
-	}).Methods("POST")
+		common.SetCORSHeaders(respAdapter, corsConfig)
+		reqAdapter := router.NewHTTPRequest(r)
+		handler.HandleOpenAPI(respAdapter, reqAdapter)
+	})
+	muxRouter.Handle("/openapi", openAPIHandler).Methods("GET", "OPTIONS")
 
-	muxRouter.HandleFunc("/{schema}/{entity}/{id}", func(w http.ResponseWriter, r *http.Request) {
-		vars := mux.Vars(r)
-		reqAdapter := router.NewHTTPRequest(r)
-		respAdapter := router.NewHTTPResponseWriter(w)
-		handler.Handle(respAdapter, reqAdapter, vars)
-	}).Methods("POST")
+	// Get all registered models from the registry
+	allModels := handler.registry.GetAllModels()
 
-	muxRouter.HandleFunc("/{schema}/{entity}", func(w http.ResponseWriter, r *http.Request) {
-		vars := mux.Vars(r)
-		reqAdapter := router.NewHTTPRequest(r)
+	// Loop through each registered model and create explicit routes
+	for fullName := range allModels {
+		// Parse the full name (e.g., "public.users" or just "users")
+		schema, entity := parseModelName(fullName)
+
+		// Build the route paths
+		entityPath := buildRoutePath(schema, entity)
+		entityWithIDPath := buildRoutePath(schema, entity) + "/{id}"
+
+		// Create handler functions for this specific entity
+		postEntityHandler := createMuxHandler(handler, schema, entity, "")
+		postEntityWithIDHandler := createMuxHandler(handler, schema, entity, "id")
+		getEntityHandler := createMuxGetHandler(handler, schema, entity, "")
+		optionsEntityHandler := createMuxOptionsHandler(handler, schema, entity, []string{"GET", "POST", "OPTIONS"})
+		optionsEntityWithIDHandler := createMuxOptionsHandler(handler, schema, entity, []string{"POST", "OPTIONS"})
+
+		// Apply authentication middleware if provided
+		if authMiddleware != nil {
+			postEntityHandler = authMiddleware(postEntityHandler).(http.HandlerFunc)
+			postEntityWithIDHandler = authMiddleware(postEntityWithIDHandler).(http.HandlerFunc)
+			getEntityHandler = authMiddleware(getEntityHandler).(http.HandlerFunc)
+			// Don't apply auth middleware to OPTIONS - CORS preflight must not require auth
+		}
+
+		// Register routes for this entity
+		muxRouter.Handle(entityPath, postEntityHandler).Methods("POST")
+		muxRouter.Handle(entityWithIDPath, postEntityWithIDHandler).Methods("POST")
+		muxRouter.Handle(entityPath, getEntityHandler).Methods("GET")
+		muxRouter.Handle(entityPath, optionsEntityHandler).Methods("OPTIONS")
+		muxRouter.Handle(entityWithIDPath, optionsEntityWithIDHandler).Methods("OPTIONS")
+	}
+}
+
+// Helper function to create Mux handler for a specific entity with CORS support
+func createMuxHandler(handler *Handler, schema, entity, idParam string) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		// Set CORS headers
+		corsConfig := common.DefaultCORSConfig()
 		respAdapter := router.NewHTTPResponseWriter(w)
+		common.SetCORSHeaders(respAdapter, corsConfig)
+
+		vars := make(map[string]string)
+		vars["schema"] = schema
+		vars["entity"] = entity
+		if idParam != "" {
+			vars["id"] = mux.Vars(r)[idParam]
+		}
+		reqAdapter := router.NewHTTPRequest(r)
+		handler.Handle(respAdapter, reqAdapter, vars)
+	}
+}
+
+// Helper function to create Mux GET handler for a specific entity with CORS support
+func createMuxGetHandler(handler *Handler, schema, entity, idParam string) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		// Set CORS headers
+		corsConfig := common.DefaultCORSConfig()
+		respAdapter := router.NewHTTPResponseWriter(w)
+		common.SetCORSHeaders(respAdapter, corsConfig)
+
+		vars := make(map[string]string)
+		vars["schema"] = schema
+		vars["entity"] = entity
+		if idParam != "" {
+			vars["id"] = mux.Vars(r)[idParam]
+		}
+		reqAdapter := router.NewHTTPRequest(r)
 		handler.HandleGet(respAdapter, reqAdapter, vars)
-	}).Methods("GET")
+	}
+}
+
+// Helper function to create Mux OPTIONS handler that returns metadata
+func createMuxOptionsHandler(handler *Handler, schema, entity string, allowedMethods []string) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		// Set CORS headers with the allowed methods for this route
+		corsConfig := common.DefaultCORSConfig()
+		corsConfig.AllowedMethods = allowedMethods
+		respAdapter := router.NewHTTPResponseWriter(w)
+		common.SetCORSHeaders(respAdapter, corsConfig)
+
+		// Return metadata in the OPTIONS response body
+		vars := make(map[string]string)
+		vars["schema"] = schema
+		vars["entity"] = entity
+		reqAdapter := router.NewHTTPRequest(r)
+		handler.HandleGet(respAdapter, reqAdapter, vars)
+	}
+}
+
+// parseModelName parses a model name like "public.users" into schema and entity
+// If no schema is present, returns empty string for schema
+func parseModelName(fullName string) (schema, entity string) {
+	parts := strings.Split(fullName, ".")
+	if len(parts) == 2 {
+		return parts[0], parts[1]
+	}
+	return "", fullName
+}
+
+// buildRoutePath builds a route path from schema and entity
+// If schema is empty, returns just "/entity", otherwise "/{schema}/{entity}"
+func buildRoutePath(schema, entity string) string {
+	if schema == "" {
+		return "/" + entity
+	}
+	return "/" + schema + "/" + entity
 }
 
 // Example usage functions for documentation:
@@ -68,12 +174,20 @@ func ExampleWithGORM(db *gorm.DB) {
 	// Create handler using GORM
 	handler := NewHandlerWithGORM(db)
 
-	// Setup router
+	// Setup router without authentication
 	muxRouter := mux.NewRouter()
-	SetupMuxRoutes(muxRouter, handler)
+	SetupMuxRoutes(muxRouter, handler, nil)
 
 	// Register models
 	// handler.RegisterModel("public", "users", &User{})
+
+	// To add authentication, pass a middleware function:
+	// import "github.com/bitechdev/ResolveSpec/pkg/security"
+	// secList := security.NewSecurityList(myProvider)
+	// authMiddleware := func(h http.Handler) http.Handler {
+	//     return security.NewAuthHandler(secList, h)
+	// }
+	// SetupMuxRoutes(muxRouter, handler, authMiddleware)
 }
 
 // ExampleWithBun shows how to switch to Bun ORM
@@ -88,60 +202,133 @@ func ExampleWithBun(bunDB *bun.DB) {
 	// Create handler
 	handler := NewHandler(dbAdapter, registry)
 
-	// Setup routes
+	// Setup routes without authentication
 	muxRouter := mux.NewRouter()
-	SetupMuxRoutes(muxRouter, handler)
+	SetupMuxRoutes(muxRouter, handler, nil)
 }
 
 // SetupBunRouterRoutes sets up bunrouter routes for the ResolveSpec API
 func SetupBunRouterRoutes(bunRouter *router.StandardBunRouterAdapter, handler *Handler) {
 	r := bunRouter.GetBunRouter()
 
-	r.Handle("POST", "/:schema/:entity", func(w http.ResponseWriter, req bunrouter.Request) error {
-		params := map[string]string{
-			"schema": req.Param("schema"),
-			"entity": req.Param("entity"),
-		}
-		reqAdapter := router.NewHTTPRequest(req.Request)
+	// CORS config
+	corsConfig := common.DefaultCORSConfig()
+
+	// Add global /openapi route
+	r.Handle("GET", "/openapi", func(w http.ResponseWriter, req bunrouter.Request) error {
 		respAdapter := router.NewHTTPResponseWriter(w)
-		handler.Handle(respAdapter, reqAdapter, params)
+		common.SetCORSHeaders(respAdapter, corsConfig)
+		reqAdapter := router.NewHTTPRequest(req.Request)
+		handler.HandleOpenAPI(respAdapter, reqAdapter)
 		return nil
 	})
 
-	r.Handle("POST", "/:schema/:entity/:id", func(w http.ResponseWriter, req bunrouter.Request) error {
-		params := map[string]string{
-			"schema": req.Param("schema"),
-			"entity": req.Param("entity"),
-			"id":     req.Param("id"),
-		}
-		reqAdapter := router.NewHTTPRequest(req.Request)
+	r.Handle("OPTIONS", "/openapi", func(w http.ResponseWriter, req bunrouter.Request) error {
 		respAdapter := router.NewHTTPResponseWriter(w)
-		handler.Handle(respAdapter, reqAdapter, params)
+		common.SetCORSHeaders(respAdapter, corsConfig)
 		return nil
 	})
 
-	r.Handle("GET", "/:schema/:entity", func(w http.ResponseWriter, req bunrouter.Request) error {
-		params := map[string]string{
-			"schema": req.Param("schema"),
-			"entity": req.Param("entity"),
-		}
-		reqAdapter := router.NewHTTPRequest(req.Request)
-		respAdapter := router.NewHTTPResponseWriter(w)
-		handler.HandleGet(respAdapter, reqAdapter, params)
-		return nil
-	})
+	// Get all registered models from the registry
+	allModels := handler.registry.GetAllModels()
 
-	r.Handle("GET", "/:schema/:entity/:id", func(w http.ResponseWriter, req bunrouter.Request) error {
-		params := map[string]string{
-			"schema": req.Param("schema"),
-			"entity": req.Param("entity"),
-			"id":     req.Param("id"),
-		}
-		reqAdapter := router.NewHTTPRequest(req.Request)
-		respAdapter := router.NewHTTPResponseWriter(w)
-		handler.HandleGet(respAdapter, reqAdapter, params)
-		return nil
-	})
+	// Loop through each registered model and create explicit routes
+	for fullName := range allModels {
+		// Parse the full name (e.g., "public.users" or just "users")
+		schema, entity := parseModelName(fullName)
+
+		// Build the route paths
+		entityPath := buildRoutePath(schema, entity)
+		entityWithIDPath := entityPath + "/:id"
+
+		// Create closure variables to capture current schema and entity
+		currentSchema := schema
+		currentEntity := entity
+
+		// POST route without ID
+		r.Handle("POST", entityPath, func(w http.ResponseWriter, req bunrouter.Request) error {
+			respAdapter := router.NewHTTPResponseWriter(w)
+			common.SetCORSHeaders(respAdapter, corsConfig)
+			params := map[string]string{
+				"schema": currentSchema,
+				"entity": currentEntity,
+			}
+			reqAdapter := router.NewHTTPRequest(req.Request)
+			handler.Handle(respAdapter, reqAdapter, params)
+			return nil
+		})
+
+		// POST route with ID
+		r.Handle("POST", entityWithIDPath, func(w http.ResponseWriter, req bunrouter.Request) error {
+			respAdapter := router.NewHTTPResponseWriter(w)
+			common.SetCORSHeaders(respAdapter, corsConfig)
+			params := map[string]string{
+				"schema": currentSchema,
+				"entity": currentEntity,
+				"id":     req.Param("id"),
+			}
+			reqAdapter := router.NewHTTPRequest(req.Request)
+			handler.Handle(respAdapter, reqAdapter, params)
+			return nil
+		})
+
+		// GET route without ID
+		r.Handle("GET", entityPath, func(w http.ResponseWriter, req bunrouter.Request) error {
+			respAdapter := router.NewHTTPResponseWriter(w)
+			common.SetCORSHeaders(respAdapter, corsConfig)
+			params := map[string]string{
+				"schema": currentSchema,
+				"entity": currentEntity,
+			}
+			reqAdapter := router.NewHTTPRequest(req.Request)
+			handler.HandleGet(respAdapter, reqAdapter, params)
+			return nil
+		})
+
+		// GET route with ID
+		r.Handle("GET", entityWithIDPath, func(w http.ResponseWriter, req bunrouter.Request) error {
+			respAdapter := router.NewHTTPResponseWriter(w)
+			common.SetCORSHeaders(respAdapter, corsConfig)
+			params := map[string]string{
+				"schema": currentSchema,
+				"entity": currentEntity,
+				"id":     req.Param("id"),
+			}
+			reqAdapter := router.NewHTTPRequest(req.Request)
+			handler.HandleGet(respAdapter, reqAdapter, params)
+			return nil
+		})
+
+		// OPTIONS route without ID (returns metadata)
+		r.Handle("OPTIONS", entityPath, func(w http.ResponseWriter, req bunrouter.Request) error {
+			respAdapter := router.NewHTTPResponseWriter(w)
+			optionsCorsConfig := corsConfig
+			optionsCorsConfig.AllowedMethods = []string{"GET", "POST", "OPTIONS"}
+			common.SetCORSHeaders(respAdapter, optionsCorsConfig)
+			params := map[string]string{
+				"schema": currentSchema,
+				"entity": currentEntity,
+			}
+			reqAdapter := router.NewHTTPRequest(req.Request)
+			handler.HandleGet(respAdapter, reqAdapter, params)
+			return nil
+		})
+
+		// OPTIONS route with ID (returns metadata)
+		r.Handle("OPTIONS", entityWithIDPath, func(w http.ResponseWriter, req bunrouter.Request) error {
+			respAdapter := router.NewHTTPResponseWriter(w)
+			optionsCorsConfig := corsConfig
+			optionsCorsConfig.AllowedMethods = []string{"POST", "OPTIONS"}
+			common.SetCORSHeaders(respAdapter, optionsCorsConfig)
+			params := map[string]string{
+				"schema": currentSchema,
+				"entity": currentEntity,
+			}
+			reqAdapter := router.NewHTTPRequest(req.Request)
+			handler.HandleGet(respAdapter, reqAdapter, params)
+			return nil
+		})
+	}
 }
 
 // ExampleWithBunRouter shows how to use bunrouter from uptrace

pkg/resolvespec/resolvespec_test.go

@@ -0,0 +1,114 @@
+package resolvespec
+
+import (
+	"testing"
+)
+
+func TestParseModelName(t *testing.T) {
+	tests := []struct {
+		name           string
+		fullName       string
+		expectedSchema string
+		expectedEntity string
+	}{
+		{
+			name:           "Model with schema",
+			fullName:       "public.users",
+			expectedSchema: "public",
+			expectedEntity: "users",
+		},
+		{
+			name:           "Model without schema",
+			fullName:       "users",
+			expectedSchema: "",
+			expectedEntity: "users",
+		},
+		{
+			name:           "Model with custom schema",
+			fullName:       "myschema.products",
+			expectedSchema: "myschema",
+			expectedEntity: "products",
+		},
+		{
+			name:           "Empty string",
+			fullName:       "",
+			expectedSchema: "",
+			expectedEntity: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			schema, entity := parseModelName(tt.fullName)
+			if schema != tt.expectedSchema {
+				t.Errorf("Expected schema '%s', got '%s'", tt.expectedSchema, schema)
+			}
+			if entity != tt.expectedEntity {
+				t.Errorf("Expected entity '%s', got '%s'", tt.expectedEntity, entity)
+			}
+		})
+	}
+}
+
+func TestBuildRoutePath(t *testing.T) {
+	tests := []struct {
+		name         string
+		schema       string
+		entity       string
+		expectedPath string
+	}{
+		{
+			name:         "With schema",
+			schema:       "public",
+			entity:       "users",
+			expectedPath: "/public/users",
+		},
+		{
+			name:         "Without schema",
+			schema:       "",
+			entity:       "users",
+			expectedPath: "/users",
+		},
+		{
+			name:         "Custom schema",
+			schema:       "admin",
+			entity:       "logs",
+			expectedPath: "/admin/logs",
+		},
+		{
+			name:         "Empty entity with schema",
+			schema:       "public",
+			entity:       "",
+			expectedPath: "/public/",
+		},
+		{
+			name:         "Both empty",
+			schema:       "",
+			entity:       "",
+			expectedPath: "/",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			path := buildRoutePath(tt.schema, tt.entity)
+			if path != tt.expectedPath {
+				t.Errorf("Expected path '%s', got '%s'", tt.expectedPath, path)
+			}
+		})
+	}
+}
+
+func TestNewStandardMuxRouter(t *testing.T) {
+	router := NewStandardMuxRouter()
+	if router == nil {
+		t.Error("Expected router to be created, got nil")
+	}
+}
+
+func TestNewStandardBunRouter(t *testing.T) {
+	router := NewStandardBunRouter()
+	if router == nil {
+		t.Error("Expected router to be created, got nil")
+	}
+}

pkg/resolvespec/security_hooks.go

@@ -0,0 +1,85 @@
+package resolvespec
+
+import (
+	"context"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
+	"github.com/bitechdev/ResolveSpec/pkg/security"
+)
+
+// RegisterSecurityHooks registers all security-related hooks with the handler
+func RegisterSecurityHooks(handler *Handler, securityList *security.SecurityList) {
+	// Hook 1: BeforeRead - Load security rules
+	handler.Hooks().Register(BeforeRead, func(hookCtx *HookContext) error {
+		secCtx := newSecurityContext(hookCtx)
+		return security.LoadSecurityRules(secCtx, securityList)
+	})
+
+	// Hook 2: BeforeScan - Apply row-level security filters
+	handler.Hooks().Register(BeforeScan, func(hookCtx *HookContext) error {
+		secCtx := newSecurityContext(hookCtx)
+		return security.ApplyRowSecurity(secCtx, securityList)
+	})
+
+	// Hook 3: AfterRead - Apply column-level security (masking)
+	handler.Hooks().Register(AfterRead, func(hookCtx *HookContext) error {
+		secCtx := newSecurityContext(hookCtx)
+		return security.ApplyColumnSecurity(secCtx, securityList)
+	})
+
+	// Hook 4 (Optional): Audit logging
+	handler.Hooks().Register(AfterRead, func(hookCtx *HookContext) error {
+		secCtx := newSecurityContext(hookCtx)
+		return security.LogDataAccess(secCtx)
+	})
+
+	logger.Info("Security hooks registered for resolvespec handler")
+}
+
+// securityContext adapts resolvespec.HookContext to security.SecurityContext interface
+type securityContext struct {
+	ctx *HookContext
+}
+
+func newSecurityContext(ctx *HookContext) security.SecurityContext {
+	return &securityContext{ctx: ctx}
+}
+
+func (s *securityContext) GetContext() context.Context {
+	return s.ctx.Context
+}
+
+func (s *securityContext) GetUserID() (int, bool) {
+	return security.GetUserID(s.ctx.Context)
+}
+
+func (s *securityContext) GetSchema() string {
+	return s.ctx.Schema
+}
+
+func (s *securityContext) GetEntity() string {
+	return s.ctx.Entity
+}
+
+func (s *securityContext) GetModel() interface{} {
+	return s.ctx.Model
+}
+
+func (s *securityContext) GetQuery() interface{} {
+	return s.ctx.Query
+}
+
+func (s *securityContext) SetQuery(query interface{}) {
+	if q, ok := query.(common.SelectQuery); ok {
+		s.ctx.Query = q
+	}
+}
+
+func (s *securityContext) GetResult() interface{} {
+	return s.ctx.Result
+}
+
+func (s *securityContext) SetResult(result interface{}) {
+	s.ctx.Result = result
+}

pkg/restheadspec/context.go

@@ -13,6 +13,7 @@ const (
 	contextKeyTableName contextKey = "tableName"
 	contextKeyModel     contextKey = "model"
 	contextKeyModelPtr  contextKey = "modelPtr"
+	contextKeyOptions   contextKey = "options"
 )
 
 // WithSchema adds schema to context
@@ -74,12 +75,28 @@ func GetModelPtr(ctx context.Context) interface{} {
 	return ctx.Value(contextKeyModelPtr)
 }
 
+// WithOptions adds request options to context
+func WithOptions(ctx context.Context, options ExtendedRequestOptions) context.Context {
+	return context.WithValue(ctx, contextKeyOptions, options)
+}
+
+// GetOptions retrieves request options from context
+func GetOptions(ctx context.Context) *ExtendedRequestOptions {
+	if v := ctx.Value(contextKeyOptions); v != nil {
+		if opts, ok := v.(ExtendedRequestOptions); ok {
+			return &opts
+		}
+	}
+	return nil
+}
+
 // WithRequestData adds all request-scoped data to context at once
-func WithRequestData(ctx context.Context, schema, entity, tableName string, model, modelPtr interface{}) context.Context {
+func WithRequestData(ctx context.Context, schema, entity, tableName string, model, modelPtr interface{}, options ExtendedRequestOptions) context.Context {
 	ctx = WithSchema(ctx, schema)
 	ctx = WithEntity(ctx, entity)
 	ctx = WithTableName(ctx, tableName)
 	ctx = WithModel(ctx, model)
 	ctx = WithModelPtr(ctx, modelPtr)
+	ctx = WithOptions(ctx, options)
 	return ctx
 }

pkg/restheadspec/context_test.go

@@ -0,0 +1,181 @@
+package restheadspec
+
+import (
+	"context"
+	"testing"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+)
+
+func TestContextOperations(t *testing.T) {
+	ctx := context.Background()
+
+	// Test Schema
+	t.Run("WithSchema and GetSchema", func(t *testing.T) {
+		ctx = WithSchema(ctx, "public")
+		schema := GetSchema(ctx)
+		if schema != "public" {
+			t.Errorf("Expected schema 'public', got '%s'", schema)
+		}
+	})
+
+	// Test Entity
+	t.Run("WithEntity and GetEntity", func(t *testing.T) {
+		ctx = WithEntity(ctx, "users")
+		entity := GetEntity(ctx)
+		if entity != "users" {
+			t.Errorf("Expected entity 'users', got '%s'", entity)
+		}
+	})
+
+	// Test TableName
+	t.Run("WithTableName and GetTableName", func(t *testing.T) {
+		ctx = WithTableName(ctx, "public.users")
+		tableName := GetTableName(ctx)
+		if tableName != "public.users" {
+			t.Errorf("Expected tableName 'public.users', got '%s'", tableName)
+		}
+	})
+
+	// Test Model
+	t.Run("WithModel and GetModel", func(t *testing.T) {
+		type TestModel struct {
+			ID   int
+			Name string
+		}
+		model := &TestModel{ID: 1, Name: "test"}
+		ctx = WithModel(ctx, model)
+		retrieved := GetModel(ctx)
+		if retrieved == nil {
+			t.Error("Expected model to be retrieved, got nil")
+		}
+		if retrievedModel, ok := retrieved.(*TestModel); ok {
+			if retrievedModel.ID != 1 || retrievedModel.Name != "test" {
+				t.Errorf("Expected model with ID=1 and Name='test', got ID=%d, Name='%s'", retrievedModel.ID, retrievedModel.Name)
+			}
+		} else {
+			t.Error("Retrieved model is not of expected type")
+		}
+	})
+
+	// Test ModelPtr
+	t.Run("WithModelPtr and GetModelPtr", func(t *testing.T) {
+		type TestModel struct {
+			ID int
+		}
+		models := []*TestModel{}
+		ctx = WithModelPtr(ctx, &models)
+		retrieved := GetModelPtr(ctx)
+		if retrieved == nil {
+			t.Error("Expected modelPtr to be retrieved, got nil")
+		}
+	})
+
+	// Test Options
+	t.Run("WithOptions and GetOptions", func(t *testing.T) {
+		limit := 10
+		options := ExtendedRequestOptions{
+			RequestOptions: common.RequestOptions{
+				Limit: &limit,
+			},
+		}
+		ctx = WithOptions(ctx, options)
+		retrieved := GetOptions(ctx)
+		if retrieved == nil {
+			t.Error("Expected options to be retrieved, got nil")
+			return
+		}
+		if retrieved.Limit == nil || *retrieved.Limit != 10 {
+			t.Error("Expected options to be retrieved with limit=10")
+		}
+	})
+
+	// Test WithRequestData
+	t.Run("WithRequestData", func(t *testing.T) {
+		type TestModel struct {
+			ID   int
+			Name string
+		}
+		model := &TestModel{ID: 1, Name: "test"}
+		modelPtr := &[]*TestModel{}
+		limit := 20
+		options := ExtendedRequestOptions{
+			RequestOptions: common.RequestOptions{
+				Limit: &limit,
+			},
+		}
+
+		ctx = WithRequestData(ctx, "test_schema", "test_entity", "test_schema.test_entity", model, modelPtr, options)
+
+		if GetSchema(ctx) != "test_schema" {
+			t.Errorf("Expected schema 'test_schema', got '%s'", GetSchema(ctx))
+		}
+		if GetEntity(ctx) != "test_entity" {
+			t.Errorf("Expected entity 'test_entity', got '%s'", GetEntity(ctx))
+		}
+		if GetTableName(ctx) != "test_schema.test_entity" {
+			t.Errorf("Expected tableName 'test_schema.test_entity', got '%s'", GetTableName(ctx))
+		}
+		if GetModel(ctx) == nil {
+			t.Error("Expected model to be set")
+		}
+		if GetModelPtr(ctx) == nil {
+			t.Error("Expected modelPtr to be set")
+		}
+		opts := GetOptions(ctx)
+		if opts == nil {
+			t.Error("Expected options to be set")
+			return
+		}
+		if opts.Limit == nil || *opts.Limit != 20 {
+			t.Error("Expected options to be set with limit=20")
+		}
+	})
+}
+
+func TestEmptyContext(t *testing.T) {
+	ctx := context.Background()
+
+	t.Run("GetSchema with empty context", func(t *testing.T) {
+		schema := GetSchema(ctx)
+		if schema != "" {
+			t.Errorf("Expected empty schema, got '%s'", schema)
+		}
+	})
+
+	t.Run("GetEntity with empty context", func(t *testing.T) {
+		entity := GetEntity(ctx)
+		if entity != "" {
+			t.Errorf("Expected empty entity, got '%s'", entity)
+		}
+	})
+
+	t.Run("GetTableName with empty context", func(t *testing.T) {
+		tableName := GetTableName(ctx)
+		if tableName != "" {
+			t.Errorf("Expected empty tableName, got '%s'", tableName)
+		}
+	})
+
+	t.Run("GetModel with empty context", func(t *testing.T) {
+		model := GetModel(ctx)
+		if model != nil {
+			t.Errorf("Expected nil model, got %v", model)
+		}
+	})
+
+	t.Run("GetModelPtr with empty context", func(t *testing.T) {
+		modelPtr := GetModelPtr(ctx)
+		if modelPtr != nil {
+			t.Errorf("Expected nil modelPtr, got %v", modelPtr)
+		}
+	})
+
+	t.Run("GetOptions with empty context", func(t *testing.T) {
+		options := GetOptions(ctx)
+		// GetOptions returns nil when context is empty
+		if options != nil {
+			t.Errorf("Expected nil options in empty context, got %v", options)
+		}
+	})
+}

pkg/restheadspec/cursor_test.go

@@ -0,0 +1,305 @@
+package restheadspec
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+)
+
+func TestGetCursorFilter_Forward(t *testing.T) {
+	opts := &ExtendedRequestOptions{
+		RequestOptions: common.RequestOptions{
+			Sort: []common.SortOption{
+				{Column: "created_at", Direction: "DESC"},
+				{Column: "id", Direction: "ASC"},
+			},
+		},
+	}
+	opts.CursorForward = "123"
+
+	tableName := "posts"
+	pkName := "id"
+	modelColumns := []string{"id", "title", "created_at", "user_id"}
+
+	filter, err := opts.GetCursorFilter(tableName, pkName, modelColumns, nil)
+	if err != nil {
+		t.Fatalf("GetCursorFilter failed: %v", err)
+	}
+
+	if filter == "" {
+		t.Fatal("Expected non-empty cursor filter")
+	}
+
+	// Verify filter contains EXISTS subquery
+	if !strings.Contains(filter, "EXISTS") {
+		t.Errorf("Filter should contain EXISTS subquery, got: %s", filter)
+	}
+
+	// Verify filter references the cursor ID
+	if !strings.Contains(filter, "123") {
+		t.Errorf("Filter should reference cursor ID 123, got: %s", filter)
+	}
+
+	// Verify filter contains the table name
+	if !strings.Contains(filter, tableName) {
+		t.Errorf("Filter should reference table name %s, got: %s", tableName, filter)
+	}
+
+	// Verify filter contains primary key
+	if !strings.Contains(filter, pkName) {
+		t.Errorf("Filter should reference primary key %s, got: %s", pkName, filter)
+	}
+
+	t.Logf("Generated cursor filter: %s", filter)
+}
+
+func TestGetCursorFilter_Backward(t *testing.T) {
+	opts := &ExtendedRequestOptions{
+		RequestOptions: common.RequestOptions{
+			Sort: []common.SortOption{
+				{Column: "created_at", Direction: "DESC"},
+				{Column: "id", Direction: "ASC"},
+			},
+		},
+	}
+	opts.CursorBackward = "456"
+
+	tableName := "posts"
+	pkName := "id"
+	modelColumns := []string{"id", "title", "created_at", "user_id"}
+
+	filter, err := opts.GetCursorFilter(tableName, pkName, modelColumns, nil)
+	if err != nil {
+		t.Fatalf("GetCursorFilter failed: %v", err)
+	}
+
+	if filter == "" {
+		t.Fatal("Expected non-empty cursor filter")
+	}
+
+	// Verify filter contains cursor ID
+	if !strings.Contains(filter, "456") {
+		t.Errorf("Filter should reference cursor ID 456, got: %s", filter)
+	}
+
+	// For backward cursor, sort direction should be reversed
+	// This is handled internally by the GetCursorFilter method
+	t.Logf("Generated backward cursor filter: %s", filter)
+}
+
+func TestGetCursorFilter_NoCursor(t *testing.T) {
+	opts := &ExtendedRequestOptions{
+		RequestOptions: common.RequestOptions{
+			Sort: []common.SortOption{
+				{Column: "created_at", Direction: "DESC"},
+			},
+		},
+	}
+	// No cursor set
+
+	tableName := "posts"
+	pkName := "id"
+	modelColumns := []string{"id", "title", "created_at"}
+
+	_, err := opts.GetCursorFilter(tableName, pkName, modelColumns, nil)
+	if err == nil {
+		t.Error("Expected error when no cursor is provided")
+	}
+
+	if !strings.Contains(err.Error(), "no cursor provided") {
+		t.Errorf("Expected 'no cursor provided' error, got: %v", err)
+	}
+}
+
+func TestGetCursorFilter_NoSort(t *testing.T) {
+	opts := &ExtendedRequestOptions{
+		RequestOptions: common.RequestOptions{
+			Sort: []common.SortOption{},
+		},
+	}
+	opts.CursorForward = "123"
+
+	tableName := "posts"
+	pkName := "id"
+	modelColumns := []string{"id", "title"}
+
+	_, err := opts.GetCursorFilter(tableName, pkName, modelColumns, nil)
+	if err == nil {
+		t.Error("Expected error when no sort columns are defined")
+	}
+
+	if !strings.Contains(err.Error(), "no sort columns") {
+		t.Errorf("Expected 'no sort columns' error, got: %v", err)
+	}
+}
+
+func TestGetCursorFilter_MultiColumnSort(t *testing.T) {
+	opts := &ExtendedRequestOptions{
+		RequestOptions: common.RequestOptions{
+			Sort: []common.SortOption{
+				{Column: "priority", Direction: "DESC"},
+				{Column: "created_at", Direction: "DESC"},
+				{Column: "id", Direction: "ASC"},
+			},
+		},
+	}
+	opts.CursorForward = "789"
+
+	tableName := "tasks"
+	pkName := "id"
+	modelColumns := []string{"id", "title", "priority", "created_at"}
+
+	filter, err := opts.GetCursorFilter(tableName, pkName, modelColumns, nil)
+	if err != nil {
+		t.Fatalf("GetCursorFilter failed: %v", err)
+	}
+
+	// Verify filter contains priority column
+	if !strings.Contains(filter, "priority") {
+		t.Errorf("Filter should reference priority column, got: %s", filter)
+	}
+
+	// Verify filter contains created_at column
+	if !strings.Contains(filter, "created_at") {
+		t.Errorf("Filter should reference created_at column, got: %s", filter)
+	}
+
+	t.Logf("Generated multi-column cursor filter: %s", filter)
+}
+
+func TestGetCursorFilter_WithSchemaPrefix(t *testing.T) {
+	opts := &ExtendedRequestOptions{
+		RequestOptions: common.RequestOptions{
+			Sort: []common.SortOption{
+				{Column: "name", Direction: "ASC"},
+			},
+		},
+	}
+	opts.CursorForward = "100"
+
+	tableName := "public.users"
+	pkName := "id"
+	modelColumns := []string{"id", "name", "email"}
+
+	filter, err := opts.GetCursorFilter(tableName, pkName, modelColumns, nil)
+	if err != nil {
+		t.Fatalf("GetCursorFilter failed: %v", err)
+	}
+
+	// Should handle schema prefix properly
+	if !strings.Contains(filter, "users") {
+		t.Errorf("Filter should reference table name users, got: %s", filter)
+	}
+
+	t.Logf("Generated cursor filter with schema: %s", filter)
+}
+
+func TestGetActiveCursor(t *testing.T) {
+	tests := []struct {
+		name              string
+		cursorForward     string
+		cursorBackward    string
+		expectedID        string
+		expectedDirection CursorDirection
+	}{
+		{
+			name:              "Forward cursor only",
+			cursorForward:     "123",
+			cursorBackward:    "",
+			expectedID:        "123",
+			expectedDirection: CursorForward,
+		},
+		{
+			name:              "Backward cursor only",
+			cursorForward:     "",
+			cursorBackward:    "456",
+			expectedID:        "456",
+			expectedDirection: CursorBackward,
+		},
+		{
+			name:              "Both cursors - forward takes precedence",
+			cursorForward:     "123",
+			cursorBackward:    "456",
+			expectedID:        "123",
+			expectedDirection: CursorForward,
+		},
+		{
+			name:              "No cursors",
+			cursorForward:     "",
+			cursorBackward:    "",
+			expectedID:        "",
+			expectedDirection: 0,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			opts := &ExtendedRequestOptions{}
+			opts.CursorForward = tt.cursorForward
+			opts.CursorBackward = tt.cursorBackward
+
+			id, direction := opts.getActiveCursor()
+
+			if id != tt.expectedID {
+				t.Errorf("Expected cursor ID %q, got %q", tt.expectedID, id)
+			}
+
+			if direction != tt.expectedDirection {
+				t.Errorf("Expected direction %d, got %d", tt.expectedDirection, direction)
+			}
+		})
+	}
+}
+
+func TestCleanSortField(t *testing.T) {
+	opts := &ExtendedRequestOptions{}
+
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		{"created_at desc", "created_at"},
+		{"name asc", "name"},
+		{"priority desc nulls last", "priority"},
+		{"id asc nulls first", "id"},
+		{"title", "title"},
+		{"updated_at DESC", "updated_at"},
+		{"  status  asc  ", "status"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			result := opts.cleanSortField(tt.input)
+			if result != tt.expected {
+				t.Errorf("cleanSortField(%q) = %q, expected %q", tt.input, result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestBuildPriorityChain(t *testing.T) {
+	clauses := []string{
+		"cursor_select.priority > posts.priority",
+		"cursor_select.created_at > posts.created_at",
+		"cursor_select.id < posts.id",
+	}
+
+	result := buildPriorityChain(clauses)
+
+	// Should build OR-AND chain for cursor comparison
+	if !strings.Contains(result, "OR") {
+		t.Error("Priority chain should contain OR operators")
+	}
+
+	if !strings.Contains(result, "AND") {
+		t.Error("Priority chain should contain AND operators for composite conditions")
+	}
+
+	// First clause should appear standalone
+	if !strings.Contains(result, clauses[0]) {
+		t.Errorf("Priority chain should contain first clause: %s", clauses[0])
+	}
+
+	t.Logf("Built priority chain: %s", result)
+}

pkg/restheadspec/handler.go

@@ -9,19 +9,27 @@ import (
 	"runtime/debug"
 	"strconv"
 	"strings"
+	"time"
 
+	"github.com/bitechdev/ResolveSpec/pkg/cache"
 	"github.com/bitechdev/ResolveSpec/pkg/common"
 	"github.com/bitechdev/ResolveSpec/pkg/logger"
 	"github.com/bitechdev/ResolveSpec/pkg/reflection"
 )
 
+// FallbackHandler is a function that handles requests when no model is found
+// It receives the same parameters as the Handle method
+type FallbackHandler func(w common.ResponseWriter, r common.Request, params map[string]string)
+
 // Handler handles API requests using database and model abstractions
 // This handler reads filters, columns, and options from HTTP headers
 type Handler struct {
-	db              common.Database
-	registry        common.ModelRegistry
-	hooks           *HookRegistry
-	nestedProcessor *common.NestedCUDProcessor
+	db               common.Database
+	registry         common.ModelRegistry
+	hooks            *HookRegistry
+	nestedProcessor  *common.NestedCUDProcessor
+	fallbackHandler  FallbackHandler
+	openAPIGenerator func() (string, error)
 }
 
 // NewHandler creates a new API handler with database and registry abstractions
@@ -36,12 +44,24 @@ func NewHandler(db common.Database, registry common.ModelRegistry) *Handler {
 	return handler
 }
 
+// GetDatabase returns the underlying database connection
+// Implements common.SpecHandler interface
+func (h *Handler) GetDatabase() common.Database {
+	return h.db
+}
+
 // Hooks returns the hook registry for this handler
 // Use this to register custom hooks for operations
 func (h *Handler) Hooks() *HookRegistry {
 	return h.hooks
 }
 
+// SetFallbackHandler sets a fallback handler to be called when no model is found
+// If not set, the handler will simply return (pass through to next route)
+func (h *Handler) SetFallbackHandler(fallback FallbackHandler) {
+	h.fallbackHandler = fallback
+}
+
 // handlePanic is a helper function to handle panics with stack traces
 func (h *Handler) handlePanic(w common.ResponseWriter, method string, err interface{}) {
 	stack := debug.Stack()
@@ -59,15 +79,18 @@ func (h *Handler) Handle(w common.ResponseWriter, r common.Request, params map[s
 		}
 	}()
 
-	ctx := context.Background()
+	// Check for ?openapi query parameter
+	if r.UnderlyingRequest().URL.Query().Get("openapi") != "" {
+		h.HandleOpenAPI(w, r)
+		return
+	}
+
+	ctx := r.UnderlyingRequest().Context()
 
 	schema := params["schema"]
 	entity := params["entity"]
 	id := params["id"]
 
-	// Parse options from headers (now returns ExtendedRequestOptions)
-	options := h.parseOptionsFromHeaders(r)
-
 	// Determine operation based on HTTP method
 	method := r.Method()
 
@@ -76,41 +99,39 @@ func (h *Handler) Handle(w common.ResponseWriter, r common.Request, params map[s
 	// Get model and populate context with request-scoped data
 	model, err := h.registry.GetModelByEntity(schema, entity)
 	if err != nil {
-		logger.Error("Invalid entity: %v", err)
-		h.sendError(w, http.StatusBadRequest, "invalid_entity", "Invalid entity", err)
+		// Model not found - call fallback handler if set, otherwise pass through
+		logger.Debug("Model not found for %s.%s", schema, entity)
+		if h.fallbackHandler != nil {
+			logger.Debug("Calling fallback handler for %s.%s", schema, entity)
+			h.fallbackHandler(w, r, params)
+		} else {
+			logger.Debug("No fallback handler set, passing through to next route")
+		}
 		return
 	}
 
-	// Validate that the model is a struct type (not a slice or pointer to slice)
-	modelType := reflect.TypeOf(model)
-	originalType := modelType
-	for modelType != nil && (modelType.Kind() == reflect.Ptr || modelType.Kind() == reflect.Slice || modelType.Kind() == reflect.Array) {
-		modelType = modelType.Elem()
-	}
-
-	if modelType == nil || modelType.Kind() != reflect.Struct {
-		logger.Error("Model for %s.%s must be a struct type, got %v. Please register models as struct types, not slices or pointers to slices.", schema, entity, originalType)
-		h.sendError(w, http.StatusInternalServerError, "invalid_model_type",
-			fmt.Sprintf("Model must be a struct type, got %v. Ensure you register the struct (e.g., ModelCoreAccount{}) not a slice (e.g., []*ModelCoreAccount)", originalType),
-			fmt.Errorf("invalid model type: %v", originalType))
+	// Validate and unwrap model using common utility
+	result, err := common.ValidateAndUnwrapModel(model)
+	if err != nil {
+		logger.Error("Model for %s.%s validation failed: %v", schema, entity, err)
+		h.sendError(w, http.StatusInternalServerError, "invalid_model_type", err.Error(), err)
 		return
 	}
 
-	// If the registered model was a pointer or slice, use the unwrapped struct type
-	if originalType != modelType {
-		model = reflect.New(modelType).Elem().Interface()
-	}
-
-	modelPtr := reflect.New(reflect.TypeOf(model)).Interface()
+	model = result.Model
+	modelPtr := result.ModelPtr
 	tableName := h.getTableName(schema, entity, model)
 
-	// Add request-scoped data to context
-	ctx = WithRequestData(ctx, schema, entity, tableName, model, modelPtr)
+	// Parse options from headers - this now includes relation name resolution
+	options := h.parseOptionsFromHeaders(r, model)
 
 	// Validate and filter columns in options (log warnings for invalid columns)
 	validator := common.NewColumnValidator(model)
 	options = filterExtendedOptions(validator, options)
 
+	// Add request-scoped data to context (including options)
+	ctx = WithRequestData(ctx, schema, entity, tableName, model, modelPtr, options)
+
 	switch method {
 	case "GET":
 		if id != "" {
@@ -121,13 +142,25 @@ func (h *Handler) Handle(w common.ResponseWriter, r common.Request, params map[s
 			h.handleRead(ctx, w, "", options)
 		}
 	case "POST":
-		// Create operation
+		// Read request body
 		body, err := r.Body()
 		if err != nil {
 			logger.Error("Failed to read request body: %v", err)
 			h.sendError(w, http.StatusBadRequest, "invalid_request", "Failed to read request body", err)
 			return
 		}
+
+		// Try to detect if this is a meta operation request
+		var bodyMap map[string]interface{}
+		if err := json.Unmarshal(body, &bodyMap); err == nil {
+			if operation, ok := bodyMap["operation"].(string); ok && operation == "meta" {
+				logger.Info("Detected meta operation request for %s.%s", schema, entity)
+				h.handleMeta(ctx, w, schema, entity, model)
+				return
+			}
+		}
+
+		// Not a meta operation, proceed with normal create/update
 		var data interface{}
 		if err := json.Unmarshal(body, &data); err != nil {
 			logger.Error("Failed to decode request body: %v", err)
@@ -182,6 +215,12 @@ func (h *Handler) HandleGet(w common.ResponseWriter, r common.Request, params ma
 		}
 	}()
 
+	// Check for ?openapi query parameter
+	if r.UnderlyingRequest().URL.Query().Get("openapi") != "" {
+		h.HandleOpenAPI(w, r)
+		return
+	}
+
 	schema := params["schema"]
 	entity := params["entity"]
 
@@ -189,11 +228,44 @@ func (h *Handler) HandleGet(w common.ResponseWriter, r common.Request, params ma
 
 	model, err := h.registry.GetModelByEntity(schema, entity)
 	if err != nil {
-		logger.Error("Failed to get model: %v", err)
-		h.sendError(w, http.StatusBadRequest, "invalid_entity", "Invalid entity", err)
+		// Model not found - call fallback handler if set, otherwise pass through
+		logger.Debug("Model not found for %s.%s", schema, entity)
+		if h.fallbackHandler != nil {
+			logger.Debug("Calling fallback handler for %s.%s", schema, entity)
+			h.fallbackHandler(w, r, params)
+		} else {
+			logger.Debug("No fallback handler set, passing through to next route")
+		}
 		return
 	}
 
+	// Parse request options from headers to get response format settings
+	options := h.parseOptionsFromHeaders(r, model)
+
+	tableMetadata := h.generateMetadata(schema, entity, model)
+	// Send with formatted response to respect DetailApi/SimpleApi/Syncfusion format
+	// Create empty metadata for response wrapper
+	responseMetadata := &common.Metadata{
+		Total:    0,
+		Filtered: 0,
+		Count:    0,
+		Limit:    0,
+		Offset:   0,
+	}
+	h.sendFormattedResponse(w, tableMetadata, responseMetadata, options)
+}
+
+// handleMeta processes meta operation requests
+func (h *Handler) handleMeta(ctx context.Context, w common.ResponseWriter, schema, entity string, model interface{}) {
+	// Capture panics and return error response
+	defer func() {
+		if err := recover(); err != nil {
+			h.handlePanic(w, "handleMeta", err)
+		}
+	}()
+
+	logger.Info("Getting metadata for %s.%s via meta operation", schema, entity)
+
 	metadata := h.generateMetadata(schema, entity, model)
 	h.sendResponse(w, metadata, nil)
 }
@@ -213,6 +285,10 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 	tableName := GetTableName(ctx)
 	model := GetModel(ctx)
 
+	if id == "" {
+		options.SingleRecordAsObject = false
+	}
+
 	// Execute BeforeRead hooks
 	hookCtx := &HookContext{
 		Context:   ctx,
@@ -260,11 +336,23 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 		query = query.Table(tableName)
 	}
 
+	// If we have computed columns/expressions but options.Columns is empty,
+	// populate it with all model columns first since computed columns are additions
+	if len(options.Columns) == 0 && (len(options.ComputedQL) > 0 || len(options.ComputedColumns) > 0) {
+		logger.Debug("Populating options.Columns with all model columns since computed columns are additions")
+		options.Columns = reflection.GetSQLModelColumns(model)
+	}
+
 	// Apply ComputedQL fields if any
 	if len(options.ComputedQL) > 0 {
 		for colName, colExpr := range options.ComputedQL {
 			logger.Debug("Applying computed column: %s", colName)
-			query = query.ColumnExpr(fmt.Sprintf("(%s) AS %s", colExpr, colName))
+			if strings.Contains(colName, "cql") {
+				query = query.ColumnExpr(fmt.Sprintf("(%s)::text AS %s", colExpr, colName))
+			} else {
+				query = query.ColumnExpr(fmt.Sprintf("(%s)AS %s", colExpr, colName))
+			}
+
 			for colIndex := range options.Columns {
 				if options.Columns[colIndex] == colName {
 					// Remove the computed column from the selected columns to avoid duplication
@@ -278,7 +366,12 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 	if len(options.ComputedColumns) > 0 {
 		for _, cu := range options.ComputedColumns {
 			logger.Debug("Applying computed column: %s", cu.Name)
-			query = query.ColumnExpr(fmt.Sprintf("(%s) AS %s", cu.Expression, cu.Name))
+			if strings.Contains(cu.Name, "cql") {
+				query = query.ColumnExpr(fmt.Sprintf("(%s)::text AS %s", cu.Expression, cu.Name))
+			} else {
+				query = query.ColumnExpr(fmt.Sprintf("(%s) AS %s", cu.Expression, cu.Name))
+			}
+
 			for colIndex := range options.Columns {
 				if options.Columns[colIndex] == cu.Name {
 					// Remove the computed column from the selected columns to avoid duplication
@@ -292,7 +385,10 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 	// Apply column selection
 	if len(options.Columns) > 0 {
 		logger.Debug("Selecting columns: %v", options.Columns)
-		query = query.Column(options.Columns...)
+		for _, col := range options.Columns {
+			query = query.Column(reflection.ExtractSourceColumn(col))
+		}
+
 	}
 
 	// Apply expand (Just expand to Preload for now)
@@ -340,50 +436,21 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 	for idx := range options.Preload {
 		preload := options.Preload[idx]
 		logger.Debug("Applying preload: %s", preload.Relation)
-		query = query.PreloadRelation(preload.Relation, func(sq common.SelectQuery) common.SelectQuery {
-			if len(preload.OmitColumns) > 0 {
-				allCols := reflection.GetModelColumns(model)
-				// Remove omitted columns
-				preload.Columns = []string{}
-				for _, col := range allCols {
-					addCols := true
-					for _, omitCol := range preload.OmitColumns {
-						if col == omitCol {
-							addCols = false
-							break
-						}
-					}
-					if addCols {
-						preload.Columns = append(preload.Columns, col)
-					}
-				}
-			}
 
-			if len(preload.Columns) > 0 {
-				sq = sq.Column(preload.Columns...)
+		// Validate and fix WHERE clause to ensure it contains the relation prefix
+		if len(preload.Where) > 0 {
+			fixedWhere, err := common.ValidateAndFixPreloadWhere(preload.Where, preload.Relation)
+			if err != nil {
+				logger.Error("Invalid preload WHERE clause for relation '%s': %v", preload.Relation, err)
+				h.sendError(w, http.StatusBadRequest, "invalid_preload_where",
+					fmt.Sprintf("Invalid preload WHERE clause for relation '%s'", preload.Relation), err)
+				return
 			}
+			preload.Where = fixedWhere
+		}
 
-			if len(preload.Filters) > 0 {
-				for _, filter := range preload.Filters {
-					sq = h.applyFilter(sq, filter, "", false, "AND")
-				}
-			}
-			if len(preload.Sort) > 0 {
-				for _, sort := range preload.Sort {
-					sq = sq.Order(fmt.Sprintf("%s %s", sort.Column, sort.Direction))
-				}
-			}
-
-			if len(preload.Where) > 0 {
-				sq = sq.Where(preload.Where)
-			}
-
-			if preload.Limit != nil && *preload.Limit > 0 {
-				sq = sq.Limit(*preload.Limit)
-			}
-
-			return sq
-		})
+		// Apply the preload with recursive support
+		query = h.applyPreloadWithRecursion(query, preload, options.Preload, model, 0)
 	}
 
 	// Apply DISTINCT if requested
@@ -413,13 +480,21 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 	// Apply custom SQL WHERE clause (AND condition)
 	if options.CustomSQLWhere != "" {
 		logger.Debug("Applying custom SQL WHERE: %s", options.CustomSQLWhere)
-		query = query.Where(options.CustomSQLWhere)
+		// Sanitize and allow preload table prefixes since custom SQL may reference multiple tables
+		sanitizedWhere := common.SanitizeWhereClause(options.CustomSQLWhere, reflection.ExtractTableNameOnly(tableName), &options.RequestOptions)
+		if sanitizedWhere != "" {
+			query = query.Where(sanitizedWhere)
+		}
 	}
 
 	// Apply custom SQL WHERE clause (OR condition)
 	if options.CustomSQLOr != "" {
 		logger.Debug("Applying custom SQL OR: %s", options.CustomSQLOr)
-		query = query.WhereOr(options.CustomSQLOr)
+		// Sanitize and allow preload table prefixes since custom SQL may reference multiple tables
+		sanitizedOr := common.SanitizeWhereClause(options.CustomSQLOr, reflection.ExtractTableNameOnly(tableName), &options.RequestOptions)
+		if sanitizedOr != "" {
+			query = query.WhereOr(sanitizedOr)
+		}
 	}
 
 	// If ID is provided, filter by ID
@@ -443,14 +518,69 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 	// Get total count before pagination (unless skip count is requested)
 	var total int
 	if !options.SkipCount {
-		count, err := query.Count(ctx)
-		if err != nil {
-			logger.Error("Error counting records: %v", err)
-			h.sendError(w, http.StatusInternalServerError, "query_error", "Error counting records", err)
-			return
+		// Try to get from cache first (unless SkipCache is true)
+		var cachedTotal *cache.CachedTotal
+		var cacheKey string
+
+		if !options.SkipCache {
+			// Build cache key from query parameters
+			// Convert expand options to interface slice for the cache key builder
+			expandOpts := make([]interface{}, len(options.Expand))
+			for i, exp := range options.Expand {
+				expandOpts[i] = map[string]interface{}{
+					"relation": exp.Relation,
+					"where":    exp.Where,
+				}
+			}
+
+			cacheKeyHash := cache.BuildExtendedQueryCacheKey(
+				tableName,
+				options.Filters,
+				options.Sort,
+				options.CustomSQLWhere,
+				options.CustomSQLOr,
+				expandOpts,
+				options.Distinct,
+				options.CursorForward,
+				options.CursorBackward,
+			)
+			cacheKey = cache.GetQueryTotalCacheKey(cacheKeyHash)
+
+			// Try to retrieve from cache
+			cachedTotal = &cache.CachedTotal{}
+			err := cache.GetDefaultCache().Get(ctx, cacheKey, cachedTotal)
+			if err == nil {
+				total = cachedTotal.Total
+				logger.Debug("Total records (from cache): %d", total)
+			} else {
+				logger.Debug("Cache miss for query total")
+				cachedTotal = nil
+			}
+		}
+
+		// If not in cache or cache skip, execute count query
+		if cachedTotal == nil {
+			count, err := query.Count(ctx)
+			if err != nil {
+				logger.Error("Error counting records: %v", err)
+				h.sendError(w, http.StatusInternalServerError, "query_error", "Error counting records", err)
+				return
+			}
+			total = count
+			logger.Debug("Total records (from query): %d", total)
+
+			// Store in cache (if caching is enabled)
+			if !options.SkipCache && cacheKey != "" {
+				cacheTTL := time.Minute * 2 // Default 2 minutes TTL
+				cacheData := &cache.CachedTotal{Total: total}
+				if err := cache.GetDefaultCache().Set(ctx, cacheKey, cacheData, cacheTTL); err != nil {
+					logger.Warn("Failed to cache query total: %v", err)
+					// Don't fail the request if caching fails
+				} else {
+					logger.Debug("Cached query total with key: %s", cacheKey)
+				}
+			}
 		}
-		total = count
-		logger.Debug("Total records: %d", total)
 	} else {
 		logger.Debug("Skipping count as requested")
 		total = -1 // Indicate count was skipped
@@ -495,7 +625,10 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 		// Apply cursor filter to query
 		if cursorFilter != "" {
 			logger.Debug("Applying cursor filter: %s", cursorFilter)
-			query = query.Where(cursorFilter)
+			sanitizedCursor := common.SanitizeWhereClause(cursorFilter, reflection.ExtractTableNameOnly(tableName), &options.RequestOptions)
+			if sanitizedCursor != "" {
+				query = query.Where(sanitizedCursor)
+			}
 		}
 	}
 
@@ -569,6 +702,144 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 	h.sendFormattedResponse(w, modelPtr, metadata, options)
 }
 
+// applyPreloadWithRecursion applies a preload with support for ComputedQL and recursive preloading
+func (h *Handler) applyPreloadWithRecursion(query common.SelectQuery, preload common.PreloadOption, allPreloads []common.PreloadOption, model interface{}, depth int) common.SelectQuery {
+	// Log relationship keys if they're specified (from XFiles)
+	if preload.RelatedKey != "" || preload.ForeignKey != "" || preload.PrimaryKey != "" {
+		logger.Debug("Preload %s has relationship keys - PK: %s, RelatedKey: %s, ForeignKey: %s",
+			preload.Relation, preload.PrimaryKey, preload.RelatedKey, preload.ForeignKey)
+
+		// Build a WHERE clause using the relationship keys if needed
+		// Note: Bun's PreloadRelation typically handles the relationship join automatically via struct tags
+		// However, if the relationship keys are explicitly provided from XFiles, we can use them
+		// to add additional filtering or validation
+		if preload.RelatedKey != "" && preload.Where == "" {
+			// For child tables: ensure the child's relatedkey column will be matched
+			// The actual parent value is dynamic and handled by Bun's preload mechanism
+			// We just log this for visibility
+			logger.Debug("Child table %s will be filtered by %s matching parent's primary key",
+				preload.Relation, preload.RelatedKey)
+		}
+		if preload.ForeignKey != "" && preload.Where == "" {
+			// For parent tables: ensure the parent's primary key matches the current table's foreign key
+			logger.Debug("Parent table %s will be filtered by primary key matching current table's %s",
+				preload.Relation, preload.ForeignKey)
+		}
+	}
+
+	// Apply the preload
+	query = query.PreloadRelation(preload.Relation, func(sq common.SelectQuery) common.SelectQuery {
+		// Get the related model for column operations
+		relatedModel := reflection.GetRelationModel(model, preload.Relation)
+		if relatedModel == nil {
+			logger.Warn("Could not get related model for preload: %s", preload.Relation)
+			// relatedModel = model // fallback to parent model
+		} else {
+
+			// If we have computed columns but no explicit columns, populate with all model columns first
+			// since computed columns are additions
+			if len(preload.Columns) == 0 && (len(preload.ComputedQL) > 0 || len(preload.OmitColumns) > 0) {
+				logger.Debug("Populating preload columns with all model columns since computed columns are additions")
+				preload.Columns = reflection.GetSQLModelColumns(relatedModel)
+			}
+
+			// Apply ComputedQL fields if any
+			if len(preload.ComputedQL) > 0 {
+				for colName, colExpr := range preload.ComputedQL {
+					logger.Debug("Applying computed column to preload %s: %s", preload.Relation, colName)
+					sq = sq.ColumnExpr(fmt.Sprintf("(%s) AS %s", colExpr, colName))
+					// Remove the computed column from selected columns to avoid duplication
+					for colIndex := range preload.Columns {
+						if preload.Columns[colIndex] == colName {
+							preload.Columns = append(preload.Columns[:colIndex], preload.Columns[colIndex+1:]...)
+							break
+						}
+					}
+				}
+			}
+
+			// Handle OmitColumns
+			if len(preload.OmitColumns) > 0 {
+				allCols := preload.Columns
+				// Remove omitted columns
+				preload.Columns = []string{}
+				for _, col := range allCols {
+					addCols := true
+					for _, omitCol := range preload.OmitColumns {
+						if col == omitCol {
+							addCols = false
+							break
+						}
+					}
+					if addCols {
+						preload.Columns = append(preload.Columns, col)
+					}
+				}
+			}
+
+			// Apply column selection
+			if len(preload.Columns) > 0 {
+				sq = sq.Column(preload.Columns...)
+			}
+		}
+
+		// Apply filters
+		if len(preload.Filters) > 0 {
+			for _, filter := range preload.Filters {
+				sq = h.applyFilter(sq, filter, "", false, "AND")
+			}
+		}
+
+		// Apply sorting
+		if len(preload.Sort) > 0 {
+			for _, sort := range preload.Sort {
+				sq = sq.Order(fmt.Sprintf("%s %s", sort.Column, sort.Direction))
+			}
+		}
+
+		// Apply WHERE clause
+		if len(preload.Where) > 0 {
+			// Build RequestOptions with all preloads to allow references to sibling relations
+			preloadOpts := &common.RequestOptions{Preload: allPreloads}
+			sanitizedWhere := common.SanitizeWhereClause(preload.Where, reflection.ExtractTableNameOnly(preload.Relation), preloadOpts)
+			if len(sanitizedWhere) > 0 {
+				sq = sq.Where(sanitizedWhere)
+			}
+		}
+
+		// Apply limit
+		if preload.Limit != nil && *preload.Limit > 0 {
+			sq = sq.Limit(*preload.Limit)
+		}
+
+		if preload.Offset != nil && *preload.Offset > 0 {
+			sq = sq.Offset(*preload.Offset)
+		}
+
+		return sq
+	})
+
+	// Handle recursive preloading
+	if preload.Recursive && depth < 5 {
+		logger.Debug("Applying recursive preload for %s at depth %d", preload.Relation, depth+1)
+
+		// For recursive relationships, we need to get the last part of the relation path
+		// e.g., "MastertaskItems" -> "MastertaskItems.MastertaskItems"
+		relationParts := strings.Split(preload.Relation, ".")
+		lastRelationName := relationParts[len(relationParts)-1]
+
+		// Create a recursive preload with the same configuration
+		// but with the relation path extended
+		recursivePreload := preload
+		recursivePreload.Relation = preload.Relation + "." + lastRelationName
+
+		// Recursively apply preload until we reach depth 5
+		query = h.applyPreloadWithRecursion(query, recursivePreload, allPreloads, model, depth+1)
+	}
+
+	return query
+}
+
 func (h *Handler) handleCreate(ctx context.Context, w common.ResponseWriter, data interface{}, options ExtendedRequestOptions) {
 	// Capture panics and return error response
 	defer func() {
@@ -663,7 +934,14 @@ func (h *Handler) handleCreate(ctx context.Context, w common.ResponseWriter, dat
 			}
 
 			// Create insert query
-			query := tx.NewInsert().Model(modelValue).Table(tableName).Returning("*")
+			query := tx.NewInsert().Model(modelValue)
+
+			// Only set Table() if the model doesn't provide a table name via TableNameProvider
+			if provider, ok := modelValue.(common.TableNameProvider); !ok || provider.TableName() == "" {
+				query = query.Table(tableName)
+			}
+
+			query = query.Returning("*")
 
 			// Execute BeforeScan hooks - pass query chain so hooks can modify it
 			itemHookCtx := &HookContext{
@@ -1222,7 +1500,7 @@ func (h *Handler) normalizeToSlice(data interface{}) []interface{} {
 func (h *Handler) extractNestedRelations(
 	data map[string]interface{},
 	model interface{},
-) (map[string]interface{}, map[string]interface{}, error) {
+) (_cleanedData map[string]interface{}, _relations map[string]interface{}, _err error) {
 	// Get model type for reflection
 	modelType := reflect.TypeOf(model)
 	for modelType != nil && (modelType.Kind() == reflect.Ptr || modelType.Kind() == reflect.Slice || modelType.Kind() == reflect.Array) {
@@ -1554,23 +1832,52 @@ func (h *Handler) generateMetadata(schema, entity string, model interface{}) *co
 	if modelType.Kind() != reflect.Struct {
 		logger.Error("Model type must be a struct, got %s for %s.%s", modelType.Kind(), schema, entity)
 		return &common.TableMetadata{
-			Schema:  schema,
-			Table:   h.getTableName(schema, entity, model),
-			Columns: []common.Column{},
+			Schema:    schema,
+			Table:     h.getTableName(schema, entity, model),
+			Columns:   []common.Column{},
+			Relations: []string{},
 		}
 	}
 
 	tableName := h.getTableName(schema, entity, model)
 
 	metadata := &common.TableMetadata{
-		Schema:  schema,
-		Table:   tableName,
-		Columns: []common.Column{},
+		Schema:    schema,
+		Table:     tableName,
+		Columns:   []common.Column{},
+		Relations: []string{},
 	}
 
 	for i := 0; i < modelType.NumField(); i++ {
 		field := modelType.Field(i)
 
+		// Skip unexported fields
+		if !field.IsExported() {
+			continue
+		}
+
+		gormTag := field.Tag.Get("gorm")
+		jsonTag := field.Tag.Get("json")
+
+		// Skip fields with json:"-"
+		if jsonTag == "-" {
+			continue
+		}
+
+		// Get JSON name
+		jsonName := strings.Split(jsonTag, ",")[0]
+		if jsonName == "" {
+			jsonName = field.Name
+		}
+
+		// Check if this is a relation field (slice or struct, but not time.Time)
+		if field.Type.Kind() == reflect.Slice ||
+			(field.Type.Kind() == reflect.Struct && field.Type.Name() != "Time") ||
+			(field.Type.Kind() == reflect.Ptr && field.Type.Elem().Kind() == reflect.Struct && field.Type.Elem().Name() != "Time") {
+			metadata.Relations = append(metadata.Relations, jsonName)
+			continue
+		}
+
 		// Get column name from gorm tag or json tag
 		columnName := field.Tag.Get("gorm")
 		if strings.Contains(columnName, "column:") {
@@ -1582,15 +1889,9 @@ func (h *Handler) generateMetadata(schema, entity string, model interface{}) *co
 				}
 			}
 		} else {
-			columnName = field.Tag.Get("json")
-			if columnName == "" || columnName == "-" {
-				columnName = strings.ToLower(field.Name)
-			}
+			columnName = jsonName
 		}
 
-		// Check for primary key and unique constraint
-		gormTag := field.Tag.Get("gorm")
-
 		column := common.Column{
 			Name:       columnName,
 			Type:       h.getColumnType(field.Type),
@@ -1640,13 +1941,10 @@ func (h *Handler) sendResponseWithOptions(w common.ResponseWriter, data interfac
 		data = h.normalizeResultArray(data)
 	}
 
-	response := common.Response{
-		Success:  true,
-		Data:     data,
-		Metadata: metadata,
-	}
+	// Return data as-is without wrapping in common.Response
+	w.SetHeader("Content-Type", "application/json")
 	w.WriteHeader(http.StatusOK)
-	if err := w.WriteJSON(response); err != nil {
+	if err := w.WriteJSON(data); err != nil {
 		logger.Error("Failed to write JSON response: %v", err)
 	}
 }
@@ -1655,7 +1953,7 @@ func (h *Handler) sendResponseWithOptions(w common.ResponseWriter, data interfac
 // Returns the single element if data is a slice/array with exactly one element, otherwise returns data unchanged
 func (h *Handler) normalizeResultArray(data interface{}) interface{} {
 	if data == nil {
-		return data
+		return nil
 	}
 
 	// Use reflection to check if data is a slice or array
@@ -1747,6 +2045,7 @@ func (h *Handler) sendError(w common.ResponseWriter, statusCode int, code, messa
 		"_error":  errorMsg,
 		"_retval": 1,
 	}
+	w.SetHeader("Content-Type", "application/json")
 	w.WriteHeader(statusCode)
 	if jsonErr := w.WriteJSON(response); jsonErr != nil {
 		logger.Error("Failed to write JSON error response: %v", jsonErr)
@@ -2095,3 +2394,35 @@ func (h *Handler) extractTagValue(tag, key string) string {
 	}
 	return ""
 }
+
+// HandleOpenAPI generates and returns the OpenAPI specification
+func (h *Handler) HandleOpenAPI(w common.ResponseWriter, r common.Request) {
+	// Import needed here to avoid circular dependency
+	// The import is done inline
+	// We'll use a factory function approach instead
+	if h.openAPIGenerator == nil {
+		logger.Error("OpenAPI generator not configured")
+		h.sendError(w, http.StatusInternalServerError, "openapi_not_configured", "OpenAPI generation not configured", nil)
+		return
+	}
+
+	spec, err := h.openAPIGenerator()
+	if err != nil {
+		logger.Error("Failed to generate OpenAPI spec: %v", err)
+		h.sendError(w, http.StatusInternalServerError, "openapi_generation_error", "Failed to generate OpenAPI specification", err)
+		return
+	}
+
+	w.SetHeader("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	_, err = w.Write([]byte(spec))
+	if err != nil {
+		logger.Error("Error sending OpenAPI spec response: %v", err)
+	}
+}
+
+// SetOpenAPIGenerator sets the OpenAPI generator function
+// This allows avoiding circular dependencies
+func (h *Handler) SetOpenAPIGenerator(generator func() (string, error)) {
+	h.openAPIGenerator = generator
+}

pkg/restheadspec/handler_nested_test.go

@@ -1,3 +1,5 @@
+// +build !integration
+
 package restheadspec
 
 import (

pkg/restheadspec/headers.go

@@ -2,6 +2,7 @@ package restheadspec
 
 import (
 	"encoding/base64"
+	"encoding/json"
 	"fmt"
 	"reflect"
 	"strconv"
@@ -9,6 +10,7 @@ import (
 
 	"github.com/bitechdev/ResolveSpec/pkg/common"
 	"github.com/bitechdev/ResolveSpec/pkg/logger"
+	"github.com/bitechdev/ResolveSpec/pkg/reflection"
 )
 
 // ExtendedRequestOptions extends common.RequestOptions with additional features
@@ -42,6 +44,9 @@ type ExtendedRequestOptions struct {
 
 	// Transaction
 	AtomicTransaction bool
+
+	// X-Files configuration - comprehensive query options as a single JSON object
+	XFiles *XFiles
 }
 
 // ExpandOption represents a relation expansion configuration
@@ -95,7 +100,8 @@ func DecodeParam(pStr string) (string, error) {
 }
 
 // parseOptionsFromHeaders parses all request options from HTTP headers
-func (h *Handler) parseOptionsFromHeaders(r common.Request) ExtendedRequestOptions {
+// If model is provided, it will resolve table names to field names in preload/expand options
+func (h *Handler) parseOptionsFromHeaders(r common.Request, model interface{}) ExtendedRequestOptions {
 	options := ExtendedRequestOptions{
 		RequestOptions: common.RequestOptions{
 			Filters: make([]common.FilterOption, 0),
@@ -105,105 +111,149 @@ func (h *Handler) parseOptionsFromHeaders(r common.Request) ExtendedRequestOptio
 		AdvancedSQL:          make(map[string]string),
 		ComputedQL:           make(map[string]string),
 		Expand:               make([]ExpandOption, 0),
-		ResponseFormat:       "simple",           // Default response format
-		SingleRecordAsObject: true,               // Default: normalize single-element arrays to objects
+		ResponseFormat:       "simple", // Default response format
+		SingleRecordAsObject: true,     // Default: normalize single-element arrays to objects
 	}
 
 	// Get all headers
 	headers := r.AllHeaders()
 
-	// Process each header
-	for key, value := range headers {
-		// Normalize header key to lowercase for consistent matching
-		normalizedKey := strings.ToLower(key)
+	// Get all query parameters
+	queryParams := r.AllQueryParams()
 
+	// Merge headers and query parameters - query parameters take precedence
+	// This allows the same parameters to be specified in either headers or query string
+	// Normalize keys to lowercase to ensure query params properly override headers
+	combinedParams := make(map[string]string)
+	for key, value := range headers {
+		combinedParams[strings.ToLower(key)] = value
+	}
+	for key, value := range queryParams {
+		combinedParams[strings.ToLower(key)] = value
+	}
+
+	// Process each parameter (from both headers and query params)
+	// Note: keys are already normalized to lowercase in combinedParams
+	for key, value := range combinedParams {
 		// Decode value if it's base64 encoded
 		decodedValue := decodeHeaderValue(value)
 
-		// Parse based on header prefix/name
+		// Parse based on parameter prefix/name
 		switch {
 		// Field Selection
-		case strings.HasPrefix(normalizedKey, "x-select-fields"):
+		case strings.HasPrefix(key, "x-select-fields"):
 			h.parseSelectFields(&options, decodedValue)
-		case strings.HasPrefix(normalizedKey, "x-not-select-fields"):
+		case strings.HasPrefix(key, "x-not-select-fields"):
 			h.parseNotSelectFields(&options, decodedValue)
-		case strings.HasPrefix(normalizedKey, "x-clean-json"):
+		case strings.HasPrefix(key, "x-clean-json"):
 			options.CleanJSON = strings.EqualFold(decodedValue, "true")
 
 		// Filtering & Search
-		case strings.HasPrefix(normalizedKey, "x-fieldfilter-"):
-			h.parseFieldFilter(&options, normalizedKey, decodedValue)
-		case strings.HasPrefix(normalizedKey, "x-searchfilter-"):
-			h.parseSearchFilter(&options, normalizedKey, decodedValue)
-		case strings.HasPrefix(normalizedKey, "x-searchop-"):
-			h.parseSearchOp(&options, normalizedKey, decodedValue, "AND")
-		case strings.HasPrefix(normalizedKey, "x-searchor-"):
-			h.parseSearchOp(&options, normalizedKey, decodedValue, "OR")
-		case strings.HasPrefix(normalizedKey, "x-searchand-"):
-			h.parseSearchOp(&options, normalizedKey, decodedValue, "AND")
-		case strings.HasPrefix(normalizedKey, "x-searchcols"):
+		case strings.HasPrefix(key, "x-fieldfilter-"):
+			h.parseFieldFilter(&options, key, decodedValue)
+		case strings.HasPrefix(key, "x-searchfilter-"):
+			h.parseSearchFilter(&options, key, decodedValue)
+		case strings.HasPrefix(key, "x-searchop-"):
+			h.parseSearchOp(&options, key, decodedValue, "AND")
+		case strings.HasPrefix(key, "x-searchor-"):
+			h.parseSearchOp(&options, key, decodedValue, "OR")
+		case strings.HasPrefix(key, "x-searchand-"):
+			h.parseSearchOp(&options, key, decodedValue, "AND")
+		case strings.HasPrefix(key, "x-searchcols"):
 			options.SearchColumns = h.parseCommaSeparated(decodedValue)
-		case strings.HasPrefix(normalizedKey, "x-custom-sql-w"):
-			options.CustomSQLWhere = decodedValue
-		case strings.HasPrefix(normalizedKey, "x-custom-sql-or"):
-			options.CustomSQLOr = decodedValue
+		case strings.HasPrefix(key, "x-custom-sql-w"):
+			if options.CustomSQLWhere != "" {
+				options.CustomSQLWhere = fmt.Sprintf("%s AND (%s)", options.CustomSQLWhere, decodedValue)
+			} else {
+				options.CustomSQLWhere = decodedValue
+			}
+		case strings.HasPrefix(key, "x-custom-sql-or"):
+			if options.CustomSQLOr != "" {
+				options.CustomSQLOr = fmt.Sprintf("%s OR (%s)", options.CustomSQLOr, decodedValue)
+			} else {
+				options.CustomSQLOr = decodedValue
+			}
 
 		// Joins & Relations
-		case strings.HasPrefix(normalizedKey, "x-preload"):
-			if strings.HasSuffix(normalizedKey, "-where") {
+		case strings.HasPrefix(key, "x-preload"):
+			if strings.HasSuffix(key, "-where") {
 				continue
 			}
-			whereClaude := headers[fmt.Sprintf("%s-where", key)]
+			whereClaude := combinedParams[fmt.Sprintf("%s-where", key)]
 			h.parsePreload(&options, decodedValue, decodeHeaderValue(whereClaude))
 
-		case strings.HasPrefix(normalizedKey, "x-expand"):
+		case strings.HasPrefix(key, "x-expand"):
 			h.parseExpand(&options, decodedValue)
-		case strings.HasPrefix(normalizedKey, "x-custom-sql-join"):
+		case strings.HasPrefix(key, "x-custom-sql-join"):
 			// TODO: Implement custom SQL join
 			logger.Debug("Custom SQL join not yet implemented: %s", decodedValue)
 
 		// Sorting & Pagination
-		case strings.HasPrefix(normalizedKey, "x-sort"):
+		case strings.HasPrefix(key, "x-sort"):
 			h.parseSorting(&options, decodedValue)
-		case strings.HasPrefix(normalizedKey, "x-limit"):
+		// Special cases for older clients using sort(a,b,-c) syntax
+		case strings.HasPrefix(key, "sort(") && strings.Contains(key, ")"):
+			sortValue := key[strings.Index(key, "(")+1 : strings.Index(key, ")")]
+			h.parseSorting(&options, sortValue)
+		case strings.HasPrefix(key, "x-limit"):
 			if limit, err := strconv.Atoi(decodedValue); err == nil {
 				options.Limit = &limit
 			}
-		case strings.HasPrefix(normalizedKey, "x-offset"):
+		// Special cases for older clients using limit(n) syntax
+		case strings.HasPrefix(key, "limit(") && strings.Contains(key, ")"):
+			limitValue := key[strings.Index(key, "(")+1 : strings.Index(key, ")")]
+			limitValueParts := strings.Split(limitValue, ",")
+
+			if len(limitValueParts) > 1 {
+				if offset, err := strconv.Atoi(limitValueParts[0]); err == nil {
+					options.Offset = &offset
+				}
+				if limit, err := strconv.Atoi(limitValueParts[1]); err == nil {
+					options.Limit = &limit
+				}
+			} else {
+				if limit, err := strconv.Atoi(limitValueParts[0]); err == nil {
+					options.Limit = &limit
+				}
+			}
+
+		case strings.HasPrefix(key, "x-offset"):
 			if offset, err := strconv.Atoi(decodedValue); err == nil {
 				options.Offset = &offset
 			}
-		case strings.HasPrefix(normalizedKey, "x-cursor-forward"):
+
+		case strings.HasPrefix(key, "x-cursor-forward"):
 			options.CursorForward = decodedValue
-		case strings.HasPrefix(normalizedKey, "x-cursor-backward"):
+		case strings.HasPrefix(key, "x-cursor-backward"):
 			options.CursorBackward = decodedValue
 
 		// Advanced Features
-		case strings.HasPrefix(normalizedKey, "x-advsql-"):
-			colName := strings.TrimPrefix(normalizedKey, "x-advsql-")
+		case strings.HasPrefix(key, "x-advsql-"):
+			colName := strings.TrimPrefix(key, "x-advsql-")
 			options.AdvancedSQL[colName] = decodedValue
-		case strings.HasPrefix(normalizedKey, "x-cql-sel-"):
-			colName := strings.TrimPrefix(normalizedKey, "x-cql-sel-")
+		case strings.HasPrefix(key, "x-cql-sel-"):
+			colName := strings.TrimPrefix(key, "x-cql-sel-")
 			options.ComputedQL[colName] = decodedValue
-		case strings.HasPrefix(normalizedKey, "x-distinct"):
+
+		case strings.HasPrefix(key, "x-distinct"):
 			options.Distinct = strings.EqualFold(decodedValue, "true")
-		case strings.HasPrefix(normalizedKey, "x-skipcount"):
+		case strings.HasPrefix(key, "x-skipcount"):
 			options.SkipCount = strings.EqualFold(decodedValue, "true")
-		case strings.HasPrefix(normalizedKey, "x-skipcache"):
+		case strings.HasPrefix(key, "x-skipcache"):
 			options.SkipCache = strings.EqualFold(decodedValue, "true")
-		case strings.HasPrefix(normalizedKey, "x-fetch-rownumber"):
+		case strings.HasPrefix(key, "x-fetch-rownumber"):
 			options.FetchRowNumber = &decodedValue
-		case strings.HasPrefix(normalizedKey, "x-pkrow"):
+		case strings.HasPrefix(key, "x-pkrow"):
 			options.PKRow = &decodedValue
 
 		// Response Format
-		case strings.HasPrefix(normalizedKey, "x-simpleapi"):
+		case strings.HasPrefix(key, "x-simpleapi"):
 			options.ResponseFormat = "simple"
-		case strings.HasPrefix(normalizedKey, "x-detailapi"):
+		case strings.HasPrefix(key, "x-detailapi"):
 			options.ResponseFormat = "detail"
-		case strings.HasPrefix(normalizedKey, "x-syncfusion"):
+		case strings.HasPrefix(key, "x-syncfusion"):
 			options.ResponseFormat = "syncfusion"
-		case strings.HasPrefix(normalizedKey, "x-single-record-as-object"):
+		case strings.HasPrefix(key, "x-single-record-as-object"):
 			// Parse as boolean - "false" disables, "true" enables (default is true)
 			if strings.EqualFold(decodedValue, "false") {
 				options.SingleRecordAsObject = false
@@ -212,11 +262,26 @@ func (h *Handler) parseOptionsFromHeaders(r common.Request) ExtendedRequestOptio
 			}
 
 		// Transaction Control
-		case strings.HasPrefix(normalizedKey, "x-transaction-atomic"):
+		case strings.HasPrefix(key, "x-transaction-atomic"):
 			options.AtomicTransaction = strings.EqualFold(decodedValue, "true")
+
+		// X-Files - comprehensive JSON configuration
+		case strings.HasPrefix(key, "x-files"):
+			h.parseXFiles(&options, decodedValue)
 		}
 	}
 
+	// Resolve relation names (convert table names to field names) if model is provided
+	if model != nil {
+		h.resolveRelationNamesInOptions(&options, model)
+	}
+
+	// Always sort according to the primary key if no sorting is specified
+	if len(options.Sort) == 0 {
+		pkName := reflection.GetPrimaryKeyName(model)
+		options.Sort = []common.SortOption{{Column: pkName, Direction: "ASC"}}
+	}
+
 	return options
 }
 
@@ -480,170 +545,419 @@ func (h *Handler) parseCommaSeparated(value string) []string {
 	return result
 }
 
-// getColumnTypeFromModel uses reflection to determine the Go type of a column in a model
-func (h *Handler) getColumnTypeFromModel(model interface{}, colName string) reflect.Kind {
-	if model == nil {
-		return reflect.Invalid
+// parseXFiles parses x-files header containing comprehensive JSON configuration
+// and populates ExtendedRequestOptions fields from it
+func (h *Handler) parseXFiles(options *ExtendedRequestOptions, value string) {
+	if value == "" {
+		return
+	}
+
+	var xfiles XFiles
+	if err := json.Unmarshal([]byte(value), &xfiles); err != nil {
+		logger.Warn("Failed to parse x-files header: %v", err)
+		return
+	}
+
+	logger.Debug("Parsed x-files configuration for table: %s", xfiles.TableName)
+
+	// Store the original XFiles for reference
+	options.XFiles = &xfiles
+
+	// Map XFiles fields to ExtendedRequestOptions
+
+	// Column selection
+	if len(xfiles.Columns) > 0 {
+		options.Columns = append(options.Columns, xfiles.Columns...)
+		logger.Debug("X-Files: Added columns: %v", xfiles.Columns)
+	}
+
+	// Omit columns
+	if len(xfiles.OmitColumns) > 0 {
+		options.OmitColumns = append(options.OmitColumns, xfiles.OmitColumns...)
+		logger.Debug("X-Files: Added omit columns: %v", xfiles.OmitColumns)
+	}
+
+	// Computed columns (CQL) -> ComputedQL
+	if len(xfiles.CQLColumns) > 0 {
+		if options.ComputedQL == nil {
+			options.ComputedQL = make(map[string]string)
+		}
+		for i, cqlExpr := range xfiles.CQLColumns {
+			colName := fmt.Sprintf("cql%d", i+1)
+			options.ComputedQL[colName] = cqlExpr
+			logger.Debug("X-Files: Added computed column %s: %s", colName, cqlExpr)
+		}
+	}
+
+	// Sorting
+	if len(xfiles.Sort) > 0 {
+		for _, sortField := range xfiles.Sort {
+			direction := "ASC"
+			colName := sortField
+
+			// Handle direction prefixes
+			if strings.HasPrefix(sortField, "-") {
+				direction = "DESC"
+				colName = strings.TrimPrefix(sortField, "-")
+			} else if strings.HasPrefix(sortField, "+") {
+				colName = strings.TrimPrefix(sortField, "+")
+			}
+
+			// Handle DESC suffix
+			if strings.HasSuffix(strings.ToLower(colName), " desc") {
+				direction = "DESC"
+				colName = strings.TrimSuffix(strings.ToLower(colName), " desc")
+			} else if strings.HasSuffix(strings.ToLower(colName), " asc") {
+				colName = strings.TrimSuffix(strings.ToLower(colName), " asc")
+			}
+
+			options.Sort = append(options.Sort, common.SortOption{
+				Column:    strings.TrimSpace(colName),
+				Direction: direction,
+			})
+		}
+		logger.Debug("X-Files: Added %d sort options", len(xfiles.Sort))
+	}
+
+	// Filter fields
+	if len(xfiles.FilterFields) > 0 {
+		for _, filterField := range xfiles.FilterFields {
+			options.Filters = append(options.Filters, common.FilterOption{
+				Column:        filterField.Field,
+				Operator:      filterField.Operator,
+				Value:         filterField.Value,
+				LogicOperator: "AND", // Default to AND
+			})
+		}
+		logger.Debug("X-Files: Added %d filter fields", len(xfiles.FilterFields))
+	}
+
+	// SQL AND conditions -> CustomSQLWhere
+	if len(xfiles.SqlAnd) > 0 {
+		if options.CustomSQLWhere != "" {
+			options.CustomSQLWhere += " AND "
+		}
+		options.CustomSQLWhere += "(" + strings.Join(xfiles.SqlAnd, " AND ") + ")"
+		logger.Debug("X-Files: Added SQL AND conditions")
+	}
+
+	// SQL OR conditions -> CustomSQLOr
+	if len(xfiles.SqlOr) > 0 {
+		if options.CustomSQLOr != "" {
+			options.CustomSQLOr += " OR "
+		}
+		options.CustomSQLOr += "(" + strings.Join(xfiles.SqlOr, " OR ") + ")"
+		logger.Debug("X-Files: Added SQL OR conditions")
+	}
+
+	// Pagination - Limit
+	if limitStr := xfiles.Limit.String(); limitStr != "" && limitStr != "0" {
+		if limitVal, err := xfiles.Limit.Int64(); err == nil && limitVal > 0 {
+			limit := int(limitVal)
+			options.Limit = &limit
+			logger.Debug("X-Files: Set limit: %d", limit)
+		}
+	}
+
+	// Pagination - Offset
+	if offsetStr := xfiles.Offset.String(); offsetStr != "" && offsetStr != "0" {
+		if offsetVal, err := xfiles.Offset.Int64(); err == nil && offsetVal > 0 {
+			offset := int(offsetVal)
+			options.Offset = &offset
+			logger.Debug("X-Files: Set offset: %d", offset)
+		}
+	}
+
+	// Cursor pagination
+	if xfiles.CursorForward != "" {
+		options.CursorForward = xfiles.CursorForward
+		logger.Debug("X-Files: Set cursor forward")
+	}
+	if xfiles.CursorBackward != "" {
+		options.CursorBackward = xfiles.CursorBackward
+		logger.Debug("X-Files: Set cursor backward")
+	}
+
+	// Flags
+	if xfiles.Skipcount {
+		options.SkipCount = true
+		logger.Debug("X-Files: Set skip count")
+	}
+
+	// Process ParentTables and ChildTables recursively
+	h.processXFilesRelations(&xfiles, options, "")
+}
+
+// processXFilesRelations processes ParentTables and ChildTables from XFiles
+// and adds them as Preload options recursively
+func (h *Handler) processXFilesRelations(xfiles *XFiles, options *ExtendedRequestOptions, basePath string) {
+	if xfiles == nil {
+		return
+	}
+
+	// Process ParentTables
+	if len(xfiles.ParentTables) > 0 {
+		logger.Debug("X-Files: Processing %d parent tables", len(xfiles.ParentTables))
+		for _, parentTable := range xfiles.ParentTables {
+			h.addXFilesPreload(parentTable, options, basePath)
+		}
+	}
+
+	// Process ChildTables
+	if len(xfiles.ChildTables) > 0 {
+		logger.Debug("X-Files: Processing %d child tables", len(xfiles.ChildTables))
+		for _, childTable := range xfiles.ChildTables {
+			h.addXFilesPreload(childTable, options, basePath)
+		}
+	}
+}
+
+// resolveRelationNamesInOptions resolves all table names to field names in preload options
+// This is called internally by parseOptionsFromHeaders when a model is provided
+func (h *Handler) resolveRelationNamesInOptions(options *ExtendedRequestOptions, model interface{}) {
+	if options == nil || model == nil {
+		return
+	}
+
+	// Resolve relation names in all preload options
+	for i := range options.Preload {
+		preload := &options.Preload[i]
+
+		// Split the relation path (e.g., "parent.child.grandchild")
+		parts := strings.Split(preload.Relation, ".")
+		resolvedParts := make([]string, 0, len(parts))
+
+		// Resolve each part of the path
+		currentModel := model
+		for _, part := range parts {
+			resolvedPart := h.resolveRelationName(currentModel, part)
+			resolvedParts = append(resolvedParts, resolvedPart)
+
+			// Try to get the model type for the next level
+			// This allows nested resolution
+			if nextModel := reflection.GetRelationModel(currentModel, resolvedPart); nextModel != nil {
+				currentModel = nextModel
+			}
+		}
+
+		// Update the relation path with resolved names
+		resolvedPath := strings.Join(resolvedParts, ".")
+		if resolvedPath != preload.Relation {
+			logger.Debug("Resolved relation path '%s' -> '%s'", preload.Relation, resolvedPath)
+			preload.Relation = resolvedPath
+		}
+	}
+
+	// Resolve relation names in expand options
+	for i := range options.Expand {
+		expand := &options.Expand[i]
+		resolved := h.resolveRelationName(model, expand.Relation)
+		if resolved != expand.Relation {
+			logger.Debug("Resolved expand relation '%s' -> '%s'", expand.Relation, resolved)
+			expand.Relation = resolved
+		}
+	}
+}
+
+// resolveRelationName resolves a relation name or table name to the actual field name in the model
+// If the input is already a field name, it returns it as-is
+// If the input is a table name, it looks up the corresponding relation field
+func (h *Handler) resolveRelationName(model interface{}, nameOrTable string) string {
+	if model == nil || nameOrTable == "" {
+		return nameOrTable
 	}
 
 	modelType := reflect.TypeOf(model)
+	if modelType == nil {
+		return nameOrTable
+	}
+
 	// Dereference pointer if needed
 	if modelType.Kind() == reflect.Ptr {
 		modelType = modelType.Elem()
 	}
 
+	// Check again after dereferencing
+	if modelType == nil {
+		return nameOrTable
+	}
+
 	// Ensure it's a struct
 	if modelType.Kind() != reflect.Struct {
-		return reflect.Invalid
+		return nameOrTable
 	}
 
-	// Find the field by JSON tag or field name
+	// First, check if the input matches a field name directly
 	for i := 0; i < modelType.NumField(); i++ {
 		field := modelType.Field(i)
+		if field.Name == nameOrTable {
+			// It's already a field name
+			// logger.Debug("Input '%s' is a field name", nameOrTable)
+			return nameOrTable
+		}
+	}
 
-		// Check JSON tag
-		jsonTag := field.Tag.Get("json")
-		if jsonTag != "" {
-			// Parse JSON tag (format: "name,omitempty")
-			parts := strings.Split(jsonTag, ",")
-			if parts[0] == colName {
-				return field.Type.Kind()
+	// If not found as a field name, try to look it up as a table name
+	normalizedInput := strings.ToLower(strings.ReplaceAll(nameOrTable, "_", ""))
+
+	for i := 0; i < modelType.NumField(); i++ {
+		field := modelType.Field(i)
+		fieldType := field.Type
+
+		// Check if it's a slice or pointer to a struct
+		var targetType reflect.Type
+		if fieldType.Kind() == reflect.Slice {
+			targetType = fieldType.Elem()
+		} else if fieldType.Kind() == reflect.Ptr {
+			targetType = fieldType.Elem()
+		}
+
+		if targetType != nil {
+			// Dereference pointer if the slice contains pointers
+			if targetType.Kind() == reflect.Ptr {
+				targetType = targetType.Elem()
+			}
+
+			// Check if it's a struct type
+			if targetType.Kind() == reflect.Struct {
+				// Get the type name and normalize it
+				typeName := targetType.Name()
+
+				// Extract the table name from type name
+				// Patterns: ModelCoreMastertaskitem -> mastertaskitem
+				//           ModelMastertaskitem -> mastertaskitem
+				normalizedTypeName := strings.ToLower(typeName)
+
+				// Remove common prefixes like "model", "modelcore", etc.
+				normalizedTypeName = strings.TrimPrefix(normalizedTypeName, "modelcore")
+				normalizedTypeName = strings.TrimPrefix(normalizedTypeName, "model")
+
+				// Compare normalized names
+				if normalizedTypeName == normalizedInput {
+					logger.Debug("Resolved table name '%s' to field '%s' (type: %s)", nameOrTable, field.Name, typeName)
+					return field.Name
+				}
 			}
 		}
+	}
 
-		// Check field name (case-insensitive)
-		if strings.EqualFold(field.Name, colName) {
-			return field.Type.Kind()
-		}
+	// If no match found, return the original input
+	logger.Debug("No field found for '%s', using as-is", nameOrTable)
+	return nameOrTable
+}
 
-		// Check snake_case conversion
-		snakeCaseName := toSnakeCase(field.Name)
-		if snakeCaseName == colName {
-			return field.Type.Kind()
+// addXFilesPreload converts an XFiles relation into a PreloadOption
+// and recursively processes its children
+func (h *Handler) addXFilesPreload(xfile *XFiles, options *ExtendedRequestOptions, basePath string) {
+	if xfile == nil || xfile.TableName == "" {
+		return
+	}
+
+	// Store the table name as-is for now - it will be resolved to field name later
+	// when we have the model instance available
+	relationPath := xfile.TableName
+	if basePath != "" {
+		relationPath = basePath + "." + xfile.TableName
+	}
+
+	logger.Debug("X-Files: Adding preload for relation: %s", relationPath)
+
+	// Create PreloadOption from XFiles configuration
+	preloadOpt := common.PreloadOption{
+		Relation:    relationPath,
+		Columns:     xfile.Columns,
+		OmitColumns: xfile.OmitColumns,
+	}
+
+	// Add sorting if specified
+	if len(xfile.Sort) > 0 {
+		preloadOpt.Sort = make([]common.SortOption, 0, len(xfile.Sort))
+		for _, sortField := range xfile.Sort {
+			direction := "ASC"
+			colName := sortField
+
+			// Handle direction prefixes
+			if strings.HasPrefix(sortField, "-") {
+				direction = "DESC"
+				colName = strings.TrimPrefix(sortField, "-")
+			} else if strings.HasPrefix(sortField, "+") {
+				colName = strings.TrimPrefix(sortField, "+")
+			}
+
+			preloadOpt.Sort = append(preloadOpt.Sort, common.SortOption{
+				Column:    strings.TrimSpace(colName),
+				Direction: direction,
+			})
 		}
 	}
 
-	return reflect.Invalid
-}
-
-// toSnakeCase converts a string from CamelCase to snake_case
-func toSnakeCase(s string) string {
-	var result strings.Builder
-	for i, r := range s {
-		if i > 0 && r >= 'A' && r <= 'Z' {
-			result.WriteRune('_')
+	// Add filters if specified
+	if len(xfile.FilterFields) > 0 {
+		preloadOpt.Filters = make([]common.FilterOption, 0, len(xfile.FilterFields))
+		for _, filterField := range xfile.FilterFields {
+			preloadOpt.Filters = append(preloadOpt.Filters, common.FilterOption{
+				Column:        filterField.Field,
+				Operator:      filterField.Operator,
+				Value:         filterField.Value,
+				LogicOperator: "AND",
+			})
 		}
-		result.WriteRune(r)
-	}
-	return strings.ToLower(result.String())
-}
-
-// isNumericType checks if a reflect.Kind is a numeric type
-func isNumericType(kind reflect.Kind) bool {
-	return kind == reflect.Int || kind == reflect.Int8 || kind == reflect.Int16 ||
-		kind == reflect.Int32 || kind == reflect.Int64 || kind == reflect.Uint ||
-		kind == reflect.Uint8 || kind == reflect.Uint16 || kind == reflect.Uint32 ||
-		kind == reflect.Uint64 || kind == reflect.Float32 || kind == reflect.Float64
-}
-
-// isStringType checks if a reflect.Kind is a string type
-func isStringType(kind reflect.Kind) bool {
-	return kind == reflect.String
-}
-
-// convertToNumericType converts a string value to the appropriate numeric type
-func convertToNumericType(value string, kind reflect.Kind) (interface{}, error) {
-	value = strings.TrimSpace(value)
-
-	switch kind {
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-		// Parse as integer
-		bitSize := 64
-		switch kind {
-		case reflect.Int8:
-			bitSize = 8
-		case reflect.Int16:
-			bitSize = 16
-		case reflect.Int32:
-			bitSize = 32
-		}
-
-		intVal, err := strconv.ParseInt(value, 10, bitSize)
-		if err != nil {
-			return nil, fmt.Errorf("invalid integer value: %w", err)
-		}
-
-		// Return the appropriate type
-		switch kind {
-		case reflect.Int:
-			return int(intVal), nil
-		case reflect.Int8:
-			return int8(intVal), nil
-		case reflect.Int16:
-			return int16(intVal), nil
-		case reflect.Int32:
-			return int32(intVal), nil
-		case reflect.Int64:
-			return intVal, nil
-		}
-
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
-		// Parse as unsigned integer
-		bitSize := 64
-		switch kind {
-		case reflect.Uint8:
-			bitSize = 8
-		case reflect.Uint16:
-			bitSize = 16
-		case reflect.Uint32:
-			bitSize = 32
-		}
-
-		uintVal, err := strconv.ParseUint(value, 10, bitSize)
-		if err != nil {
-			return nil, fmt.Errorf("invalid unsigned integer value: %w", err)
-		}
-
-		// Return the appropriate type
-		switch kind {
-		case reflect.Uint:
-			return uint(uintVal), nil
-		case reflect.Uint8:
-			return uint8(uintVal), nil
-		case reflect.Uint16:
-			return uint16(uintVal), nil
-		case reflect.Uint32:
-			return uint32(uintVal), nil
-		case reflect.Uint64:
-			return uintVal, nil
-		}
-
-	case reflect.Float32, reflect.Float64:
-		// Parse as float
-		bitSize := 64
-		if kind == reflect.Float32 {
-			bitSize = 32
-		}
-
-		floatVal, err := strconv.ParseFloat(value, bitSize)
-		if err != nil {
-			return nil, fmt.Errorf("invalid float value: %w", err)
-		}
-
-		if kind == reflect.Float32 {
-			return float32(floatVal), nil
-		}
-		return floatVal, nil
 	}
 
-	return nil, fmt.Errorf("unsupported numeric type: %v", kind)
-}
+	// Add WHERE clause if SQL conditions specified
+	whereConditions := make([]string, 0)
+	if len(xfile.SqlAnd) > 0 {
+		whereConditions = append(whereConditions, xfile.SqlAnd...)
+	}
+	if len(whereConditions) > 0 {
+		preloadOpt.Where = strings.Join(whereConditions, " AND ")
+	}
 
-// isNumericValue checks if a string value can be parsed as a number
-func isNumericValue(value string) bool {
-	value = strings.TrimSpace(value)
-	_, err := strconv.ParseFloat(value, 64)
-	return err == nil
+	// Add limit if specified
+	if limitStr := xfile.Limit.String(); limitStr != "" && limitStr != "0" {
+		if limitVal, err := xfile.Limit.Int64(); err == nil && limitVal > 0 {
+			limit := int(limitVal)
+			preloadOpt.Limit = &limit
+		}
+	}
+
+	// Add computed columns (CQL) -> ComputedQL
+	if len(xfile.CQLColumns) > 0 {
+		preloadOpt.ComputedQL = make(map[string]string)
+		for i, cqlExpr := range xfile.CQLColumns {
+			colName := fmt.Sprintf("cql%d", i+1)
+			preloadOpt.ComputedQL[colName] = cqlExpr
+			logger.Debug("X-Files: Added computed column %s to preload %s: %s", colName, relationPath, cqlExpr)
+		}
+	}
+
+	// Set recursive flag
+	preloadOpt.Recursive = xfile.Recursive
+
+	// Extract relationship keys for proper foreign key filtering
+	if xfile.PrimaryKey != "" {
+		preloadOpt.PrimaryKey = xfile.PrimaryKey
+		logger.Debug("X-Files: Set primary key for %s: %s", relationPath, xfile.PrimaryKey)
+	}
+	if xfile.RelatedKey != "" {
+		preloadOpt.RelatedKey = xfile.RelatedKey
+		logger.Debug("X-Files: Set related key for %s: %s", relationPath, xfile.RelatedKey)
+	}
+	if xfile.ForeignKey != "" {
+		preloadOpt.ForeignKey = xfile.ForeignKey
+		logger.Debug("X-Files: Set foreign key for %s: %s", relationPath, xfile.ForeignKey)
+	}
+
+	// Add the preload option
+	options.Preload = append(options.Preload, preloadOpt)
+
+	// Recursively process nested ParentTables and ChildTables
+	if xfile.Recursive {
+		logger.Debug("X-Files: Recursive preload enabled for: %s", relationPath)
+		h.processXFilesRelations(xfile, options, relationPath)
+	} else if len(xfile.ParentTables) > 0 || len(xfile.ChildTables) > 0 {
+		h.processXFilesRelations(xfile, options, relationPath)
+	}
 }
 
 // ColumnCastInfo holds information about whether a column needs casting
@@ -659,7 +973,7 @@ func (h *Handler) ValidateAndAdjustFilterForColumnType(filter *common.FilterOpti
 		return ColumnCastInfo{NeedsCast: false, IsNumericType: false}
 	}
 
-	colType := h.getColumnTypeFromModel(model, filter.Column)
+	colType := reflection.GetColumnTypeFromModel(model, filter.Column)
 	if colType == reflect.Invalid {
 		// Column not found in model, no casting needed
 		logger.Debug("Column %s not found in model, skipping type validation", filter.Column)
@@ -670,18 +984,18 @@ func (h *Handler) ValidateAndAdjustFilterForColumnType(filter *common.FilterOpti
 	valueIsNumeric := false
 	if strVal, ok := filter.Value.(string); ok {
 		strVal = strings.Trim(strVal, "%")
-		valueIsNumeric = isNumericValue(strVal)
+		valueIsNumeric = reflection.IsNumericValue(strVal)
 	}
 
 	// Adjust based on column type
 	switch {
-	case isNumericType(colType):
+	case reflection.IsNumericType(colType):
 		// Column is numeric
 		if valueIsNumeric {
 			// Value is numeric - try to convert it
 			if strVal, ok := filter.Value.(string); ok {
 				strVal = strings.Trim(strVal, "%")
-				numericVal, err := convertToNumericType(strVal, colType)
+				numericVal, err := reflection.ConvertToNumericType(strVal, colType)
 				if err != nil {
 					logger.Debug("Failed to convert value '%s' to numeric type for column %s, will use text cast", strVal, filter.Column)
 					return ColumnCastInfo{NeedsCast: true, IsNumericType: true}
@@ -696,7 +1010,7 @@ func (h *Handler) ValidateAndAdjustFilterForColumnType(filter *common.FilterOpti
 			return ColumnCastInfo{NeedsCast: true, IsNumericType: true}
 		}
 
-	case isStringType(colType):
+	case reflection.IsStringType(colType):
 		// String columns don't need casting
 		return ColumnCastInfo{NeedsCast: false, IsNumericType: false}
 

pkg/restheadspec/headers_test.go

@@ -0,0 +1,46 @@
+package restheadspec
+
+import (
+	"testing"
+)
+
+func TestDecodeHeaderValue(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "Normal string",
+			input:    "test",
+			expected: "test",
+		},
+		{
+			name:     "String without encoding prefix",
+			input:    "hello world",
+			expected: "hello world",
+		},
+		{
+			name:     "Empty string",
+			input:    "",
+			expected: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := decodeHeaderValue(tt.input)
+			if result != tt.expected {
+				t.Errorf("Expected '%s', got '%s'", tt.expected, result)
+			}
+		})
+	}
+}
+
+// Note: The following functions are unexported (lowercase) and cannot be tested directly:
+// - parseSelectFields
+// - parseFieldFilter
+// - mapSearchOperator
+// - parseCommaSeparated
+// - parseSorting
+// These are tested indirectly through parseOptionsFromHeaders in query_params_test.go

pkg/restheadspec/integration_test.go

@@ -0,0 +1,556 @@
+// +build integration
+
+package restheadspec
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/gorilla/mux"
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+	"gorm.io/gorm/logger"
+
+	"github.com/bitechdev/ResolveSpec/pkg/common"
+)
+
+// Test models
+type TestUser struct {
+	ID        uint      `gorm:"primaryKey" json:"id"`
+	Name      string    `gorm:"not null" json:"name"`
+	Email     string    `gorm:"uniqueIndex;not null" json:"email"`
+	Age       int       `json:"age"`
+	Active    bool      `gorm:"default:true" json:"active"`
+	CreatedAt time.Time `json:"created_at"`
+	Posts     []TestPost `gorm:"foreignKey:UserID" json:"posts,omitempty"`
+}
+
+func (TestUser) TableName() string {
+	return "test_users"
+}
+
+type TestPost struct {
+	ID        uint      `gorm:"primaryKey" json:"id"`
+	UserID    uint      `gorm:"not null" json:"user_id"`
+	Title     string    `gorm:"not null" json:"title"`
+	Content   string    `json:"content"`
+	Published bool      `gorm:"default:false" json:"published"`
+	CreatedAt time.Time `json:"created_at"`
+	User      *TestUser  `gorm:"foreignKey:UserID" json:"user,omitempty"`
+	Comments  []TestComment `gorm:"foreignKey:PostID" json:"comments,omitempty"`
+}
+
+func (TestPost) TableName() string {
+	return "test_posts"
+}
+
+type TestComment struct {
+	ID        uint      `gorm:"primaryKey" json:"id"`
+	PostID    uint      `gorm:"not null" json:"post_id"`
+	Content   string    `gorm:"not null" json:"content"`
+	CreatedAt time.Time `json:"created_at"`
+	Post      *TestPost  `gorm:"foreignKey:PostID" json:"post,omitempty"`
+}
+
+func (TestComment) TableName() string {
+	return "test_comments"
+}
+
+// Test helper functions
+func setupTestDB(t *testing.T) *gorm.DB {
+	// Get connection string from environment or use default
+	dsn := os.Getenv("TEST_DATABASE_URL")
+	if dsn == "" {
+		dsn = "host=localhost user=postgres password=postgres dbname=restheadspec_test port=5434 sslmode=disable"
+	}
+
+	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{
+		Logger: logger.Default.LogMode(logger.Silent),
+	})
+	if err != nil {
+		t.Skipf("Skipping integration test: database not available: %v", err)
+		return nil
+	}
+
+	// Run migrations
+	err = db.AutoMigrate(&TestUser{}, &TestPost{}, &TestComment{})
+	if err != nil {
+		t.Skipf("Skipping integration test: failed to migrate database: %v", err)
+		return nil
+	}
+
+	return db
+}
+
+func cleanupTestDB(t *testing.T, db *gorm.DB) {
+	// Clean up test data
+	db.Exec("TRUNCATE TABLE test_comments CASCADE")
+	db.Exec("TRUNCATE TABLE test_posts CASCADE")
+	db.Exec("TRUNCATE TABLE test_users CASCADE")
+}
+
+func createTestData(t *testing.T, db *gorm.DB) {
+	users := []TestUser{
+		{Name: "John Doe", Email: "john@example.com", Age: 30, Active: true},
+		{Name: "Jane Smith", Email: "jane@example.com", Age: 25, Active: true},
+		{Name: "Bob Johnson", Email: "bob@example.com", Age: 35, Active: false},
+	}
+
+	for i := range users {
+		if err := db.Create(&users[i]).Error; err != nil {
+			t.Fatalf("Failed to create test user: %v", err)
+		}
+	}
+
+	posts := []TestPost{
+		{UserID: users[0].ID, Title: "First Post", Content: "Hello World", Published: true},
+		{UserID: users[0].ID, Title: "Second Post", Content: "More content", Published: true},
+		{UserID: users[1].ID, Title: "Jane's Post", Content: "Jane's content", Published: false},
+	}
+
+	for i := range posts {
+		if err := db.Create(&posts[i]).Error; err != nil {
+			t.Fatalf("Failed to create test post: %v", err)
+		}
+	}
+
+	comments := []TestComment{
+		{PostID: posts[0].ID, Content: "Great post!"},
+		{PostID: posts[0].ID, Content: "Thanks for sharing"},
+		{PostID: posts[1].ID, Content: "Interesting"},
+	}
+
+	for i := range comments {
+		if err := db.Create(&comments[i]).Error; err != nil {
+			t.Fatalf("Failed to create test comment: %v", err)
+		}
+	}
+}
+
+// Integration tests
+func TestIntegration_GetAllUsers(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.registry.RegisterModel("public.test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	req := httptest.NewRequest("GET", "/public/test_users", nil)
+	req.Header.Set("X-DetailApi", "true")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	if response.Metadata == nil {
+		t.Fatal("Expected metadata, got nil")
+	}
+
+	if response.Metadata.Total != 3 {
+		t.Errorf("Expected 3 users, got %d", response.Metadata.Total)
+	}
+}
+
+func TestIntegration_GetUsersWithFilters(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.registry.RegisterModel("public.test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Filter: age > 25
+	req := httptest.NewRequest("GET", "/public/test_users", nil)
+	req.Header.Set("X-DetailApi", "true")
+	req.Header.Set("X-SearchOp-Gt-Age", "25")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	// Should return 2 users (John: 30, Bob: 35)
+	if response.Metadata.Total != 2 {
+		t.Errorf("Expected 2 filtered users, got %d", response.Metadata.Total)
+	}
+}
+
+func TestIntegration_GetUsersWithPagination(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.registry.RegisterModel("public.test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	req := httptest.NewRequest("GET", "/public/test_users", nil)
+	req.Header.Set("X-DetailApi", "true")
+	req.Header.Set("X-Limit", "2")
+	req.Header.Set("X-Offset", "1")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d", w.Code)
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	// Total should still be 3, but we're only retrieving 2 records starting from offset 1
+	if response.Metadata.Total != 3 {
+		t.Errorf("Expected total 3 users, got %d", response.Metadata.Total)
+	}
+
+	if response.Metadata.Limit != 2 {
+		t.Errorf("Expected limit 2, got %d", response.Metadata.Limit)
+	}
+
+	if response.Metadata.Offset != 1 {
+		t.Errorf("Expected offset 1, got %d", response.Metadata.Offset)
+	}
+}
+
+func TestIntegration_GetUsersWithSorting(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.registry.RegisterModel("public.test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Sort by age descending
+	req := httptest.NewRequest("GET", "/public/test_users", nil)
+	req.Header.Set("X-DetailApi", "true")
+	req.Header.Set("X-Sort", "-age")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d", w.Code)
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	// Parse data to verify sort order
+	dataBytes, _ := json.Marshal(response.Data)
+	var users []TestUser
+	json.Unmarshal(dataBytes, &users)
+
+	if len(users) < 3 {
+		t.Fatal("Expected at least 3 users")
+	}
+
+	// Check that users are sorted by age descending (Bob:35, John:30, Jane:25)
+	if users[0].Age < users[1].Age || users[1].Age < users[2].Age {
+		t.Error("Expected users to be sorted by age descending")
+	}
+}
+
+func TestIntegration_GetUsersWithColumnsSelection(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.registry.RegisterModel("public.test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	req := httptest.NewRequest("GET", "/public/test_users", nil)
+	req.Header.Set("X-DetailApi", "true")
+	req.Header.Set("X-Columns", "id,name,email")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	// Verify data was returned (column selection doesn't affect metadata count)
+	if response.Metadata.Total != 3 {
+		t.Errorf("Expected 3 users, got %d", response.Metadata.Total)
+	}
+}
+
+func TestIntegration_GetUsersWithPreload(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.registry.RegisterModel("public.test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	req := httptest.NewRequest("GET", "/public/test_users?x-fieldfilter-email=john@example.com", nil)
+	req.Header.Set("X-DetailApi", "true")
+	req.Header.Set("X-Preload", "Posts")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	// Verify posts are preloaded
+	dataBytes, _ := json.Marshal(response.Data)
+	var users []TestUser
+	json.Unmarshal(dataBytes, &users)
+
+	if len(users) == 0 {
+		t.Fatal("Expected at least one user")
+	}
+
+	if len(users[0].Posts) == 0 {
+		t.Error("Expected posts to be preloaded")
+	}
+}
+
+func TestIntegration_GetMetadata(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.registry.RegisterModel("public.test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	req := httptest.NewRequest("GET", "/public/test_users/metadata", nil)
+	req.Header.Set("X-DetailApi", "true")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v. Body: %s, Error: %v", response.Success, w.Body.String(), response.Error)
+	}
+
+	// Check that metadata includes columns
+	metadataBytes, _ := json.Marshal(response.Data)
+	var metadata common.TableMetadata
+	json.Unmarshal(metadataBytes, &metadata)
+
+	if len(metadata.Columns) == 0 {
+		t.Error("Expected metadata to contain columns")
+	}
+
+	// Verify some expected columns
+	hasID := false
+	hasName := false
+	hasEmail := false
+	for _, col := range metadata.Columns {
+		if col.Name == "id" {
+			hasID = true
+		}
+		if col.Name == "name" {
+			hasName = true
+		}
+		if col.Name == "email" {
+			hasEmail = true
+		}
+	}
+
+	if !hasID || !hasName || !hasEmail {
+		t.Error("Expected metadata to contain 'id', 'name', and 'email' columns")
+	}
+}
+
+func TestIntegration_OptionsRequest(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.registry.RegisterModel("public.test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	req := httptest.NewRequest("OPTIONS", "/public/test_users", nil)
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d", w.Code)
+	}
+
+	// Check CORS headers
+	if w.Header().Get("Access-Control-Allow-Origin") == "" {
+		t.Error("Expected Access-Control-Allow-Origin header")
+	}
+
+	if w.Header().Get("Access-Control-Allow-Methods") == "" {
+		t.Error("Expected Access-Control-Allow-Methods header")
+	}
+}
+
+func TestIntegration_QueryParamsOverHeaders(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.registry.RegisterModel("public.test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Query params should override headers
+	req := httptest.NewRequest("GET", "/public/test_users?x-limit=1", nil)
+	req.Header.Set("X-DetailApi", "true")
+	req.Header.Set("X-Limit", "10")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d", w.Code)
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	// Query param should win (limit=1)
+	if response.Metadata.Limit != 1 {
+		t.Errorf("Expected limit 1 from query param, got %d", response.Metadata.Limit)
+	}
+}
+
+func TestIntegration_GetSingleRecord(t *testing.T) {
+	db := setupTestDB(t)
+	defer cleanupTestDB(t, db)
+	createTestData(t, db)
+
+	handler := NewHandlerWithGORM(db)
+	handler.registry.RegisterModel("public.test_users", TestUser{})
+
+	muxRouter := mux.NewRouter()
+	SetupMuxRoutes(muxRouter, handler, nil)
+
+	// Get first user ID
+	var user TestUser
+	db.Where("email = ?", "john@example.com").First(&user)
+
+	req := httptest.NewRequest("GET", fmt.Sprintf("/public/test_users/%d", user.ID), nil)
+	req.Header.Set("X-DetailApi", "true")
+	w := httptest.NewRecorder()
+
+	muxRouter.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status 200, got %d. Body: %s", w.Code, w.Body.String())
+	}
+
+	var response common.Response
+	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+		t.Fatalf("Failed to parse response: %v", err)
+	}
+
+	if !response.Success {
+		t.Errorf("Expected success=true, got %v", response.Success)
+	}
+
+	// Verify it's a single record
+	dataBytes, _ := json.Marshal(response.Data)
+	var resultUser TestUser
+	json.Unmarshal(dataBytes, &resultUser)
+
+	if resultUser.Email != "john@example.com" {
+		t.Errorf("Expected user with email 'john@example.com', got '%s'", resultUser.Email)
+	}
+}

pkg/restheadspec/query_params_test.go

@@ -0,0 +1,410 @@
+package restheadspec
+
+import (
+	"net/http"
+	"testing"
+)
+
+// MockRequest implements common.Request interface for testing
+type MockRequest struct {
+	headers     map[string]string
+	queryParams map[string]string
+}
+
+func (m *MockRequest) Method() string {
+	return "GET"
+}
+
+func (m *MockRequest) URL() string {
+	return "http://example.com/test"
+}
+
+func (m *MockRequest) Header(key string) string {
+	return m.headers[key]
+}
+
+func (m *MockRequest) AllHeaders() map[string]string {
+	return m.headers
+}
+
+func (m *MockRequest) Body() ([]byte, error) {
+	return nil, nil
+}
+
+func (m *MockRequest) PathParam(key string) string {
+	return ""
+}
+
+func (m *MockRequest) QueryParam(key string) string {
+	return m.queryParams[key]
+}
+
+func (m *MockRequest) AllQueryParams() map[string]string {
+	return m.queryParams
+}
+
+func (m *MockRequest) UnderlyingRequest() *http.Request {
+	// For testing purposes, return nil
+	// In real scenarios, you might want to construct a proper http.Request
+	return nil
+}
+
+func TestParseOptionsFromQueryParams(t *testing.T) {
+	handler := NewHandler(nil, nil)
+
+	tests := []struct {
+		name        string
+		queryParams map[string]string
+		headers     map[string]string
+		validate    func(t *testing.T, options ExtendedRequestOptions)
+	}{
+		{
+			name: "Parse custom SQL WHERE from query params",
+			queryParams: map[string]string{
+				"x-custom-sql-w-1": `("v_webui_clients".clientstatus = 0 or "v_webui_clients".clientstatus is null)`,
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if options.CustomSQLWhere == "" {
+					t.Error("Expected CustomSQLWhere to be set from query param")
+				}
+				expected := `("v_webui_clients".clientstatus = 0 or "v_webui_clients".clientstatus is null)`
+				if options.CustomSQLWhere != expected {
+					t.Errorf("Expected CustomSQLWhere=%q, got %q", expected, options.CustomSQLWhere)
+				}
+			},
+		},
+		{
+			name: "Parse sort from query params",
+			queryParams: map[string]string{
+				"x-sort": "-applicationdate,name",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if len(options.Sort) != 2 {
+					t.Errorf("Expected 2 sort options, got %d", len(options.Sort))
+					return
+				}
+				if options.Sort[0].Column != "applicationdate" || options.Sort[0].Direction != "DESC" {
+					t.Errorf("Expected first sort: applicationdate DESC, got %s %s", options.Sort[0].Column, options.Sort[0].Direction)
+				}
+				if options.Sort[1].Column != "name" || options.Sort[1].Direction != "ASC" {
+					t.Errorf("Expected second sort: name ASC, got %s %s", options.Sort[1].Column, options.Sort[1].Direction)
+				}
+			},
+		},
+		{
+			name: "Parse limit and offset from query params",
+			queryParams: map[string]string{
+				"x-limit":  "100",
+				"x-offset": "50",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if options.Limit == nil || *options.Limit != 100 {
+					t.Errorf("Expected limit=100, got %v", options.Limit)
+				}
+				if options.Offset == nil || *options.Offset != 50 {
+					t.Errorf("Expected offset=50, got %v", options.Offset)
+				}
+			},
+		},
+		{
+			name: "Parse field filters from query params",
+			queryParams: map[string]string{
+				"x-fieldfilter-status": "active",
+				"x-fieldfilter-type":   "user",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if len(options.Filters) != 2 {
+					t.Errorf("Expected 2 filters, got %d", len(options.Filters))
+					return
+				}
+				// Check that filters were created
+				foundStatus := false
+				foundType := false
+				for _, filter := range options.Filters {
+					if filter.Column == "status" && filter.Value == "active" && filter.Operator == "eq" {
+						foundStatus = true
+					}
+					if filter.Column == "type" && filter.Value == "user" && filter.Operator == "eq" {
+						foundType = true
+					}
+				}
+				if !foundStatus {
+					t.Error("Expected status filter not found")
+				}
+				if !foundType {
+					t.Error("Expected type filter not found")
+				}
+			},
+		},
+		{
+			name: "Parse select fields from query params",
+			queryParams: map[string]string{
+				"x-select-fields": "id,name,email",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if len(options.Columns) != 3 {
+					t.Errorf("Expected 3 columns, got %d", len(options.Columns))
+					return
+				}
+				expected := []string{"id", "name", "email"}
+				for i, col := range expected {
+					if i >= len(options.Columns) || options.Columns[i] != col {
+						t.Errorf("Expected column[%d]=%s, got %v", i, col, options.Columns)
+					}
+				}
+			},
+		},
+		{
+			name: "Parse preload from query params",
+			queryParams: map[string]string{
+				"x-preload": "posts:title,content|comments",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if len(options.Preload) != 2 {
+					t.Errorf("Expected 2 preload options, got %d", len(options.Preload))
+					return
+				}
+				// Check first preload (posts with columns)
+				if options.Preload[0].Relation != "posts" {
+					t.Errorf("Expected first preload relation=posts, got %s", options.Preload[0].Relation)
+				}
+				if len(options.Preload[0].Columns) != 2 {
+					t.Errorf("Expected 2 columns for posts preload, got %d", len(options.Preload[0].Columns))
+				}
+				// Check second preload (comments without columns)
+				if options.Preload[1].Relation != "comments" {
+					t.Errorf("Expected second preload relation=comments, got %s", options.Preload[1].Relation)
+				}
+			},
+		},
+		{
+			name: "Query params take precedence over headers",
+			queryParams: map[string]string{
+				"x-limit": "100",
+			},
+			headers: map[string]string{
+				"X-Limit": "50",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if options.Limit == nil || *options.Limit != 100 {
+					t.Errorf("Expected query param limit=100 to override header, got %v", options.Limit)
+				}
+			},
+		},
+		{
+			name: "Parse search operators from query params",
+			queryParams: map[string]string{
+				"x-searchop-contains-name": "john",
+				"x-searchop-gt-age":        "18",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if len(options.Filters) != 2 {
+					t.Errorf("Expected 2 filters, got %d", len(options.Filters))
+					return
+				}
+				// Check for ILIKE filter
+				foundContains := false
+				foundGt := false
+				for _, filter := range options.Filters {
+					if filter.Column == "name" && filter.Operator == "ilike" {
+						foundContains = true
+					}
+					if filter.Column == "age" && filter.Operator == "gt" && filter.Value == "18" {
+						foundGt = true
+					}
+				}
+				if !foundContains {
+					t.Error("Expected contains filter not found")
+				}
+				if !foundGt {
+					t.Error("Expected gt filter not found")
+				}
+			},
+		},
+		{
+			name: "Parse complex example with multiple params",
+			queryParams: map[string]string{
+				"x-custom-sql-w-1":     `("v_webui_clients".clientstatus = 0)`,
+				"x-sort":               "-applicationdate",
+				"x-limit":              "100",
+				"x-select-fields":      "id,name,status",
+				"x-fieldfilter-active": "true",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				// Validate CustomSQLWhere
+				if options.CustomSQLWhere == "" {
+					t.Error("Expected CustomSQLWhere to be set")
+				}
+				// Validate Sort
+				if len(options.Sort) != 1 || options.Sort[0].Column != "applicationdate" || options.Sort[0].Direction != "DESC" {
+					t.Errorf("Expected sort by applicationdate DESC, got %v", options.Sort)
+				}
+				// Validate Limit
+				if options.Limit == nil || *options.Limit != 100 {
+					t.Errorf("Expected limit=100, got %v", options.Limit)
+				}
+				// Validate Columns
+				if len(options.Columns) != 3 {
+					t.Errorf("Expected 3 columns, got %d", len(options.Columns))
+				}
+				// Validate Filters
+				if len(options.Filters) < 1 {
+					t.Error("Expected at least 1 filter")
+				}
+			},
+		},
+		{
+			name: "Parse distinct flag from query params",
+			queryParams: map[string]string{
+				"x-distinct": "true",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if !options.Distinct {
+					t.Error("Expected Distinct to be true")
+				}
+			},
+		},
+		{
+			name: "Parse skip count flag from query params",
+			queryParams: map[string]string{
+				"x-skipcount": "true",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if !options.SkipCount {
+					t.Error("Expected SkipCount to be true")
+				}
+			},
+		},
+		{
+			name: "Parse response format from query params",
+			queryParams: map[string]string{
+				"x-syncfusion": "true",
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if options.ResponseFormat != "syncfusion" {
+					t.Errorf("Expected ResponseFormat=syncfusion, got %s", options.ResponseFormat)
+				}
+			},
+		},
+		{
+			name: "Parse custom SQL OR from query params",
+			queryParams: map[string]string{
+				"x-custom-sql-or": `("field1" = 'value1' OR "field2" = 'value2')`,
+			},
+			validate: func(t *testing.T, options ExtendedRequestOptions) {
+				if options.CustomSQLOr == "" {
+					t.Error("Expected CustomSQLOr to be set")
+				}
+				expected := `("field1" = 'value1' OR "field2" = 'value2')`
+				if options.CustomSQLOr != expected {
+					t.Errorf("Expected CustomSQLOr=%q, got %q", expected, options.CustomSQLOr)
+				}
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Create mock request
+			req := &MockRequest{
+				headers:     tt.headers,
+				queryParams: tt.queryParams,
+			}
+			if req.headers == nil {
+				req.headers = make(map[string]string)
+			}
+			if req.queryParams == nil {
+				req.queryParams = make(map[string]string)
+			}
+
+			// Parse options
+			options := handler.parseOptionsFromHeaders(req, nil)
+
+			// Validate
+			tt.validate(t, options)
+		})
+	}
+}
+
+func TestQueryParamsWithURLEncoding(t *testing.T) {
+	handler := NewHandler(nil, nil)
+
+	// Test with URL-encoded query parameter (like the user's example)
+	req := &MockRequest{
+		headers: make(map[string]string),
+		queryParams: map[string]string{
+			// URL-encoded version of the SQL WHERE clause
+			"x-custom-sql-w-1": `("v_webui_clients".clientstatus = 0 or "v_webui_clients".clientstatus is null) and ("v_webui_clients".inactive = 0 or "v_webui_clients".inactive is null)`,
+		},
+	}
+
+	options := handler.parseOptionsFromHeaders(req, nil)
+
+	if options.CustomSQLWhere == "" {
+		t.Error("Expected CustomSQLWhere to be set from URL-encoded query param")
+	}
+
+	// The SQL should contain the expected conditions
+	if !contains(options.CustomSQLWhere, "clientstatus") {
+		t.Error("Expected CustomSQLWhere to contain 'clientstatus'")
+	}
+	if !contains(options.CustomSQLWhere, "inactive") {
+		t.Error("Expected CustomSQLWhere to contain 'inactive'")
+	}
+}
+
+func TestHeadersAndQueryParamsCombined(t *testing.T) {
+	handler := NewHandler(nil, nil)
+
+	// Test that headers and query params can work together
+	req := &MockRequest{
+		headers: map[string]string{
+			"X-Select-Fields": "id,name",
+			"X-Limit":         "50",
+		},
+		queryParams: map[string]string{
+			"x-sort":   "-created_at",
+			"x-offset": "10",
+			// This should override the header value
+			"x-limit": "100",
+		},
+	}
+
+	options := handler.parseOptionsFromHeaders(req, nil)
+
+	// Verify columns from header
+	if len(options.Columns) != 2 {
+		t.Errorf("Expected 2 columns from header, got %d", len(options.Columns))
+	}
+
+	// Verify sort from query param
+	if len(options.Sort) != 1 || options.Sort[0].Column != "created_at" {
+		t.Errorf("Expected sort from query param, got %v", options.Sort)
+	}
+
+	// Verify offset from query param
+	if options.Offset == nil || *options.Offset != 10 {
+		t.Errorf("Expected offset=10 from query param, got %v", options.Offset)
+	}
+
+	// Verify limit from query param (should override header)
+	if options.Limit == nil {
+		t.Error("Expected limit to be set from query param")
+	} else if *options.Limit != 100 {
+		t.Errorf("Expected limit=100 from query param (overriding header), got %d", *options.Limit)
+	}
+}
+
+// Helper function to check if a string contains a substring
+func contains(s, substr string) bool {
+	return len(s) >= len(substr) && (s == substr || len(s) > len(substr) && containsHelper(s, substr))
+}
+
+func containsHelper(s, substr string) bool {
+	for i := 0; i <= len(s)-len(substr); i++ {
+		if s[i:i+len(substr)] == substr {
+			return true
+		}
+	}
+	return false
+}