schema-typegen

Welcome to schema-typegen 👋

Generate TypeScript type definitions from database schema.

Install

npm install schema-typegen

Usage

For now only Postgres is supported.

Usage: schema-typegen [opts] connection_string

Example:
schema-typegen -o ./entities.ts postgres://username:password@localhost:5432/database

Available options:

  -f/--suffix SUFFIX
        Suffix to append to generated table type, e.g. item -> ItemEntity. Default: 'Entity'.
  -s/--schema SCHEMA
        Schema. Default: 'public'.
  -h/--header HEADER
        Header content. Default: ''.
  -o/--output OUTPUT_PATH
        Output path, e.g. './entities.ts'. Default: outputs to stdout.
  -e/--exclude EXCLUDE
        Excluded tables and enums as comma separated string e.g. knex_migrations,knex_migrations_lock  Default: ''.
  --types
        Use type definitions instead of interfaces in generated output. Default: false.
  --no-semicolons
        Omit semicolons in generated types. Default: false.
  --ssl
        Use ssl. Default: false.
  --optionals
        Use optionals "?" instead of null. Default: false.
  --pascal-enums
        Transform enum keys to pascal case. Default: false.
  --bigint
        Use bigint for int8 types instead of strings. Default: false.
  -v/--version
        Print the version number.
  -h/--help
        Print this menu.

Given database table

CREATE TYPE user_state AS ENUM (
  'asleep',
  'awake'
);

CREATE TABLE users (
    id int4 NOT NULL,
    name varchar(255),
    state user_state,
    is_enabled bool NOT NULL DEFAULT FALSE
);

Running schema-typegen -o ./entities.ts postgres://username:password@localhost:5432/database Will generate the following type definitions

enum UserState {
  asleep = 'asleep',
  awake = 'awake'
}

interface UserEntity {
  id: number;
  name: string | null;
  state: UserState | null;
  is_enabled: boolean;
}

Running from code

import { join } from 'path'
import generate from 'schema-typegen'
;(async () => {
  const output = join(__dirname, 'entities.ts')
  await generate({ connection: 'postgres://username:password@localhost:5432/database', output })
})()

Loading database config

from .env file

export $(grep -v '^#' .env | xargs) && schema-typegen -o ./entities.ts postgres://$DB_USERNAME:$DB_PASSWORD@$DB_HOST:$DB_PORT/$DB_NAME

from json file

schema-typegen -o ./entities.ts postgres://$(jq -r '.DB.USERNAME' config.json):$(jq -r '.DB.PASSWORD' config.json)@$(jq -r '.DB.HOST' config.json):$(jq -r '.DB.PORT' config.json)/$(jq -r '.DB.NAME' config.json)

Run tests

docker-compose up -d
npm test

Contributing

Contributions, issues and feature requests are welcome!

License

Copyright © 2020 Aldis Ameriks.
This project is MIT licensed.