cql_columns parsing and recursive preloading. Also added legacy header support for limt(s,e) ,sort(x,y,-z)

pkg/common/adapters/router/bunrouter.go

@@ -121,6 +121,16 @@ 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 {

pkg/common/adapters/router/mux.go

@@ -117,6 +117,16 @@ 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 {

pkg/common/interfaces.go

@@ -116,6 +116,7 @@ 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
 }
 
 // ResponseWriter interface abstracts HTTP response

pkg/common/types.go

@@ -32,15 +32,17 @@ 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
 }
 
 type FilterOption struct {

pkg/reflection/model_utils.go

@@ -323,6 +323,127 @@ 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

pkg/reflection/model_utils_test.go

@@ -474,3 +474,143 @@ func TestIsColumnWritableWithEmbedded(t *testing.T) {
 		})
 	}
 }
+
+// Test models with relations for GetSQLModelColumns
+type User struct {
+	ID          int       `bun:"id,pk" json:"id"`
+	Name        string    `bun:"name" json:"name"`
+	Email       string    `bun:"email" json:"email"`
+	ProfileData string    `json:"profile_data"` // No bun/gorm tag
+	Posts       []Post    `bun:"rel:has-many,join:id=user_id" json:"posts"`
+	Profile     *Profile  `bun:"rel:has-one,join:id=user_id" json:"profile"`
+	RowNumber   int64     `bun:",scanonly" json:"_rownumber"`
+}
+
+type Post struct {
+	ID      int    `gorm:"column:id;primaryKey" json:"id"`
+	Title   string `gorm:"column:title" json:"title"`
+	UserID  int    `gorm:"column:user_id;foreignKey" json:"user_id"`
+	User    *User  `gorm:"foreignKey:UserID;references:ID" json:"user"`
+	Tags    []Tag  `gorm:"many2many:post_tags" json:"tags"`
+	Content string `json:"content"` // No bun/gorm tag
+}
+
+type Profile struct {
+	ID     int    `bun:"id,pk" json:"id"`
+	Bio    string `bun:"bio" json:"bio"`
+	UserID int    `bun:"user_id" json:"user_id"`
+}
+
+type Tag struct {
+	ID   int    `gorm:"column:id;primaryKey" json:"id"`
+	Name string `gorm:"column:name" json:"name"`
+}
+
+// Model with scan-only embedded struct
+type EntityWithScanOnlyEmbedded struct {
+	ID          int    `bun:"id,pk" json:"id"`
+	Name        string `bun:"name" json:"name"`
+	AdhocBuffer `bun:",scanonly"` // Entire embedded struct is scan-only
+}
+
+func TestGetSQLModelColumns(t *testing.T) {
+	tests := []struct {
+		name     string
+		model    any
+		expected []string
+	}{
+		{
+			name:  "Bun model with relations - excludes relations and non-SQL fields",
+			model: User{},
+			// Should include: id, name, email (has bun tags)
+			// Should exclude: profile_data (no bun tag), Posts/Profile (relations), RowNumber (scan-only in embedded would be excluded)
+			expected: []string{"id", "name", "email"},
+		},
+		{
+			name:  "GORM model with relations - excludes relations and non-SQL fields",
+			model: Post{},
+			// Should include: id, title, user_id (has gorm tags)
+			// Should exclude: content (no gorm tag), User/Tags (relations)
+			expected: []string{"id", "title", "user_id"},
+		},
+		{
+			name:  "Model with embedded base and scan-only embedded",
+			model: EntityWithScanOnlyEmbedded{},
+			// Should include: id, name from main struct
+			// Should exclude: all fields from AdhocBuffer (scan-only embedded struct)
+			expected: []string{"id", "name"},
+		},
+		{
+			name:  "Model with embedded - includes SQL fields, excludes scan-only",
+			model: ModelWithEmbedded{},
+			// Should include: rid_base, created_at (from BaseModel), name, description (from main)
+			// Should exclude: cql1, cql2, _rownumber (from AdhocBuffer - scan-only fields)
+			expected: []string{"rid_base", "created_at", "name", "description"},
+		},
+		{
+			name:  "GORM model with embedded - includes SQL fields, excludes scan-only",
+			model: GormModelWithEmbedded{},
+			// Should include: rid_base, created_at (from GormBaseModel), name, description (from main)
+			// Should exclude: cql1, cql2 (scan-only), _rownumber (no gorm column tag, marked as -)
+			expected: []string{"rid_base", "created_at", "name", "description"},
+		},
+		{
+			name:  "Simple Profile model",
+			model: Profile{},
+			// Should include all fields with bun tags
+			expected: []string{"id", "bio", "user_id"},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := GetSQLModelColumns(tt.model)
+			if len(result) != len(tt.expected) {
+				t.Errorf("GetSQLModelColumns() returned %d columns, want %d.\nGot: %v\nWant: %v",
+					len(result), len(tt.expected), result, tt.expected)
+				return
+			}
+			for i, col := range result {
+				if col != tt.expected[i] {
+					t.Errorf("GetSQLModelColumns()[%d] = %v, want %v.\nFull result: %v",
+						i, col, tt.expected[i], result)
+				}
+			}
+		})
+	}
+}
+
+func TestGetSQLModelColumnsVsGetModelColumns(t *testing.T) {
+	// Demonstrate the difference between GetModelColumns and GetSQLModelColumns
+	user := User{}
+
+	allColumns := GetModelColumns(user)
+	sqlColumns := GetSQLModelColumns(user)
+
+	t.Logf("GetModelColumns(User): %v", allColumns)
+	t.Logf("GetSQLModelColumns(User): %v", sqlColumns)
+
+	// GetModelColumns should return more columns (includes fields with only json tags)
+	if len(allColumns) <= len(sqlColumns) {
+		t.Errorf("Expected GetModelColumns to return more columns than GetSQLModelColumns")
+	}
+
+	// GetSQLModelColumns should not include 'profile_data' (no bun tag)
+	for _, col := range sqlColumns {
+		if col == "profile_data" {
+			t.Errorf("GetSQLModelColumns should not include 'profile_data' (no bun/gorm tag)")
+		}
+	}
+
+	// GetModelColumns should include 'profile_data' (has json tag)
+	hasProfileData := false
+	for _, col := range allColumns {
+		if col == "profile_data" {
+			hasProfileData = true
+			break
+		}
+	}
+	if !hasProfileData {
+		t.Errorf("GetModelColumns should include 'profile_data' (has json tag)")
+	}
+}

pkg/resolvespec/handler.go

@@ -191,6 +191,11 @@ 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)
@@ -1145,7 +1150,7 @@ func (h *Handler) applyPreloads(model interface{}, query common.SelectQuery, pre
 		logger.Debug("Applying preload: %s", relationFieldName)
 		query = query.PreloadRelation(relationFieldName, func(sq common.SelectQuery) common.SelectQuery {
 			if len(preload.OmitColumns) > 0 {
-				allCols := reflection.GetModelColumns(model)
+				allCols := reflection.GetSQLModelColumns(model)
 				// Remove omitted columns
 				preload.Columns = []string{}
 				for _, col := range allCols {

pkg/restheadspec/handler.go

@@ -264,7 +264,7 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 	// 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.GetModelColumns(model)
+		options.Columns = reflection.GetSQLModelColumns(model)
 	}
 
 	// Apply ComputedQL fields if any
@@ -360,50 +360,8 @@ func (h *Handler) handleRead(ctx context.Context, w common.ResponseWriter, id st
 			preload.Where = fixedWhere
 		}
 
-		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...)
-			}
-
-			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, model, 0)
 	}
 
 	// Apply DISTINCT if requested
@@ -589,6 +547,111 @@ 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, model interface{}, depth int) common.SelectQuery {
+	// Apply the preload
+	query = query.PreloadRelation(preload.Relation, func(sq common.SelectQuery) common.SelectQuery {
+		// Get the related model for column operations
+		relatedModel := h.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
+		}
+
+		// 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 && relatedModel != nil {
+			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 && relatedModel != nil {
+			allCols := reflection.GetModelColumns(relatedModel)
+			// 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 {
+			sq = sq.Where(preload.Where)
+		}
+
+		// Apply limit
+		if preload.Limit != nil && *preload.Limit > 0 {
+			sq = sq.Limit(*preload.Limit)
+		}
+
+		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, 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() {

pkg/restheadspec/headers.go

@@ -110,22 +110,35 @@ func (h *Handler) parseOptionsFromHeaders(r common.Request, model interface{}) E
 		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
+	// 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
+	combinedParams := make(map[string]string)
 	for key, value := range headers {
-		// Normalize header key to lowercase for consistent matching
+		combinedParams[key] = value
+	}
+	for key, value := range queryParams {
+		combinedParams[key] = value
+	}
+
+	// Process each parameter (from both headers and query params)
+	for key, value := range combinedParams {
+		// Normalize parameter key to lowercase for consistent matching
 		normalizedKey := strings.ToLower(key)
 
 		// 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"):
@@ -158,7 +171,7 @@ func (h *Handler) parseOptionsFromHeaders(r common.Request, model interface{}) E
 			if strings.HasSuffix(normalizedKey, "-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"):
@@ -170,14 +183,37 @@ func (h *Handler) parseOptionsFromHeaders(r common.Request, model interface{}) E
 		// Sorting & Pagination
 		case strings.HasPrefix(normalizedKey, "x-sort"):
 			h.parseSorting(&options, decodedValue)
+		//Special cases for older clients using sort(a,b,-c) syntax
+		case strings.HasPrefix(normalizedKey, "sort(") && strings.Contains(normalizedKey, ")"):
+			sortValue := normalizedKey[strings.Index(normalizedKey, "(")+1 : strings.Index(normalizedKey, ")")]
+			h.parseSorting(&options, sortValue)
 		case strings.HasPrefix(normalizedKey, "x-limit"):
 			if limit, err := strconv.Atoi(decodedValue); err == nil {
 				options.Limit = &limit
 			}
+		//Special cases for older clients using limit(n) syntax
+		case strings.HasPrefix(normalizedKey, "limit(") && strings.Contains(normalizedKey, ")"):
+			limitValue := normalizedKey[strings.Index(normalizedKey, "(")+1 : strings.Index(normalizedKey, ")")]
+			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(normalizedKey, "x-offset"):
 			if offset, err := strconv.Atoi(decodedValue); err == nil {
 				options.Offset = &offset
 			}
+
 		case strings.HasPrefix(normalizedKey, "x-cursor-forward"):
 			options.CursorForward = decodedValue
 		case strings.HasPrefix(normalizedKey, "x-cursor-backward"):
@@ -922,6 +958,19 @@ func (h *Handler) addXFilesPreload(xfile *XFiles, options *ExtendedRequestOption
 		}
 	}
 
+	// 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
+
 	// Add the preload option
 	options.Preload = append(options.Preload, preloadOpt)
 

pkg/restheadspec/query_params_test.go

@@ -0,0 +1,403 @@
+package restheadspec
+
+import (
+	"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 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
+}