Schema-typegen NPM

Generate TypeScript type definitions from database schema.

Install

npm install schema-typegen

Usage

For now only Postgres is supported.

Usage: schema-typegen [options] <connection>

Options:
  -V, --version              output the version number
  -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>      file output path (default: "stdout")
  -e, --exclude <exclude>    excluded tables and enums as comma separated string e.g. knex_migrations,knex_migrations_lock (default: [])
  --type                     use type definitions instead of interfaces in generated output (default: false)
  --noSemi, --no-semicolons  omit semicolons in generated types
  --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)
  --date-as-string           use string for date types instead of javascript Date object (default: false)
  --help                     display help for command

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

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)