YAML Reader
Reads database schema definitions from YAML files.
Overview
The YAML Reader parses YAML files that define database schemas in RelSpec's canonical YAML format and converts them into RelSpec's internal database model representation.
Features
- Reads RelSpec's standard YAML schema format
- Human-readable alternative to JSON format
- Supports complete schema representation including:
- Databases and schemas
- Tables, columns, and data types
- Constraints (PK, FK, unique, check)
- Indexes
- Relationships
- Views and sequences
Usage
Basic Example
package main
import (
"fmt"
"git.warky.dev/wdevs/relspecgo/pkg/readers"
"git.warky.dev/wdevs/relspecgo/pkg/readers/yaml"
)
func main() {
options := &readers.ReaderOptions{
FilePath: "/path/to/schema.yaml",
}
reader := yaml.NewReader(options)
db, err := reader.ReadDatabase()
if err != nil {
panic(err)
}
fmt.Printf("Found %d schemas\n", len(db.Schemas))
}
CLI Example
# Read YAML schema and convert to GORM models
relspec --input yaml --in-file schema.yaml --output gorm --out-file models.go
# Convert YAML to PostgreSQL DDL
relspec --input yaml --in-file database.yaml --output pgsql --out-file schema.sql
# Transform YAML to JSON
relspec --input yaml --in-file schema.yaml --output json --out-file schema.json
Example YAML Schema
name: myapp
database_type: postgresql
schemas:
- name: public
tables:
- name: users
schema: public
columns:
id:
name: id
type: bigint
not_null: true
is_primary_key: true
auto_increment: true
sequence: 1
username:
name: username
type: varchar
length: 50
not_null: true
sequence: 2
email:
name: email
type: varchar
length: 100
not_null: true
sequence: 3
constraints:
pk_users:
name: pk_users
type: PRIMARY KEY
columns:
- id
uq_users_username:
name: uq_users_username
type: UNIQUE
columns:
- username
indexes:
idx_users_email:
name: idx_users_email
columns:
- email
unique: false
type: btree
- name: posts
schema: public
columns:
id:
name: id
type: bigint
not_null: true
is_primary_key: true
sequence: 1
user_id:
name: user_id
type: bigint
not_null: true
sequence: 2
title:
name: title
type: varchar
length: 200
not_null: true
sequence: 3
constraints:
fk_posts_user_id:
name: fk_posts_user_id
type: FOREIGN KEY
columns:
- user_id
referenced_table: users
referenced_schema: public
referenced_columns:
- id
on_delete: CASCADE
on_update: NO ACTION
Schema Structure
The YAML format mirrors RelSpec's internal model structure with human-readable syntax:
- Database level:
name,database_type,schemas - Schema level:
name,tables,views,sequences - Table level:
name,schema,columns,constraints,indexes,relationships - Column level:
name,type,length,not_null,default, etc.
Notes
- YAML format is more human-readable than JSON
- Ideal for manual editing and version control
- Comments are supported in YAML
- Preserves complete schema information
- Can be used for configuration and documentation