Get Started with SchemaGen

🚀 Quick Start

Get up and running with SchemaGen in less than 5 minutes.

export SCHEMAGEN_API_KEY=your_api_key_here

curl -X POST https://api.schemagen.tech/v1/generate \
  -H "Authorization: Bearer $SCHEMAGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "description": "Create a user table with email, password, and name",
    "format": "json-schema"
  }'

⚙️ Installation

CLI Installation

npm install -g @schemagen/cli

yarn global add @schemagen/cli

pip install schemagen

schemagen --version

💻 Basic Usage

Using the CLI

schemagen generate \
  --description "User model with email, password, and optional profile info" \
  --format json-schema \
  --output user.schema.json

schemagen migrate \
  --description "User table with email, password, created_at" \
  --database postgresql \
  --output migrations/001_create_users.sql

schemagen data \
  --schema user.schema.json \
  --count 100 \
  --output sample-users.json

Using the API

// JavaScript/Node.js
const SchemaGen = require('@schemagen/sdk');

const client = new SchemaGen({
  apiKey: process.env.SCHEMAGEN_API_KEY
});

const result = await client.generate({
  description: 'Product catalog with SKU, name, price, and inventory',
  format: 'json-schema',
  options: {
    strict: true,
    includeExamples: true
  }
});

console.log(result.schema);

📋 JSON Schema Generation

SchemaGen generates fully compliant JSON Schema (Draft 7, 2019-09, 2020-12) with rich validation rules.

Example

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "title": "User",
  "description": "User account schema",
  "required": ["email"],
  "properties": {
    "email": {
      "type": "string",
      "format": "email",
      "description": "User email address",
      "examples": ["user@example.com"]
    },
    "age": {
      "type": "integer",
      "minimum": 18,
      "maximum": 120,
      "description": "User age"
    },
    "roles": {
      "type": "array",
      "items": {
        "type": "string",
        "enum": ["user", "admin", "moderator"]
      },
      "minItems": 1,
      "uniqueItems": true,
      "description": "User roles"
    }
  },
  "additionalProperties": false
}

🗄️ Database Migrations

Generate production-ready migration scripts for any database. Includes proper indexes, constraints, and rollback plans.

Supported Databases

PostgreSQL Example

-- Migration: 20260118_create_users_table.up.sql
-- Generated by SchemaGen

CREATE TABLE IF NOT EXISTS users (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  email VARCHAR(255) NOT NULL UNIQUE,
  password_hash VARCHAR(255) NOT NULL,
  name VARCHAR(100),
  age INTEGER CHECK (age >= 18 AND age <= 120),
  roles TEXT[] NOT NULL DEFAULT ARRAY['user']::TEXT[],
  created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP,
  updated_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP
);

-- Indexes for performance
CREATE INDEX idx_users_email ON users(email);
CREATE INDEX idx_users_created_at ON users(created_at);

-- Trigger to automatically update updated_at
CREATE OR REPLACE FUNCTION update_updated_at_column()
RETURNS TRIGGER AS $$
BEGIN
  NEW.updated_at = CURRENT_TIMESTAMP;
  RETURN NEW;
END;
$$ language 'plpgsql';

CREATE TRIGGER update_users_updated_at
  BEFORE UPDATE ON users
  FOR EACH ROW
  EXECUTE FUNCTION update_updated_at_column();

Rollback Script

-- Migration: 20260118_create_users_table.down.sql
-- Rollback generated by SchemaGen

DROP TRIGGER IF EXISTS update_users_updated_at ON users;
DROP FUNCTION IF EXISTS update_updated_at_column();
DROP INDEX IF EXISTS idx_users_created_at;
DROP INDEX IF EXISTS idx_users_email;
DROP TABLE IF EXISTS users;

📊 Sample Data Generation

Generate realistic test data that respects all your schema constraints and validation rules.

CLI Usage

schemagen data \
  --schema user.schema.json \
  --count 1000 \
  --format json \
  --output test-data.json

API Usage

const data = await client.generateData({
  schema: userSchema,
  count: 100,
  options: {
    realistic: true,
    locale: 'en_US'
  }
});

🔄 CI/CD Integration

Integrate schema validation into your CI/CD pipeline to catch breaking changes before they reach production.

GitHub Actions

# .github/workflows/schema-validation.yml
name: Schema Validation

on:
  pull_request:
    paths:
      - 'schemas/**'

jobs:
  validate:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      
      - name: Setup Node.js
        uses: actions/setup-node@v3
        with:
          node-version: '18'
      
      - name: Install SchemaGen CLI
        run: npm install -g @schemagen/cli
      
      - name: Validate Schemas
        env:
          SCHEMAGEN_API_KEY: ${{ secrets.SCHEMAGEN_API_KEY }}
        run: |
          schemagen validate ./schemas/**/*.json
          
      - name: Check for Breaking Changes
        env:
          SCHEMAGEN_API_KEY: ${{ secrets.SCHEMAGEN_API_KEY }}
        run: |
          schemagen diff \
            --base main \
            --head HEAD \
            --fail-on-breaking

GitLab CI

# .gitlab-ci.yml
schema_validation:
  stage: test
  image: node:18
  before_script:
    - npm install -g @schemagen/cli
  script:
    - schemagen validate ./schemas
    - schemagen diff --base main --head HEAD --fail-on-breaking
  only:
    - merge_requests
  variables:
    SCHEMAGEN_API_KEY: $API_KEY

📡 API Reference

Complete REST API for programmatic access to all SchemaGen features.

https://api.schemagen.tech/v1

Authorization: Bearer YOUR_API_KEY

Need Help?

We're here to help you get the most out of SchemaGen.