schemagen

Database migration CLI - generate schemas from JSON/TypeScript

Installation

npm install -g @mazhu/schemagen

Usage

Initialize a new migration project

schemagen init -n my-project
cd my-project

Generate migration from JSON schema

schemagen generate schemas/my-schema.json -d postgres

Run pending migrations

schemagen migrate -d postgres

Rollback last migration

schemagen rollback -d postgres

Show migration status

schemagen status -d postgres

Schema Format

{
  "users": {
    "id": { "type": "uuid", "primaryKey": true },
    "email": { "type": "varchar", "length": 255, "unique": true, "notNull": true },
    "name": { "type": "varchar", "length": 255 },
    "created_at": { "type": "timestamp", "default": "now()" }
  },
  "posts": {
    "id": { "type": "uuid", "primaryKey": true },
    "user_id": { "type": "uuid", "references": { "table": "users", "column": "id" } },
    "title": { "type": "varchar", "length": 500, "notNull": true },
    "content": { "type": "text" },
    "published": { "type": "boolean", "default": false },
    "created_at": { "type": "timestamp", "default": "now()" },
    "updated_at": { "type": "timestamp", "default": "now()" }
  }
}

Supported Dialects

• PostgreSQL
• MySQL
• SQLite

Configuration

Create a .schemagen/config.json file:

{
  "dialect": "postgres",
  "migrationsDir": "migrations",
  "schemasDir": "schemas",
  "connection": {
    "host": "localhost",
    "port": 5432,
    "database": "mydb",
    "user": "postgres",
    "password": ""
  }
}

License

MIT