gen-ts-type

Generate Typescript type from sample data

Installation

npm i -g gen-ts-type

Usage

From cli

echo 'export type Package = ' | tee package.d.ts
format=1 allowEmptyArray=1 allowMultiTypedArray=1 gen-ts-type package.json | tee -a package.d.ts

From typescript

import { genTsType } from 'gen-ts-type';
import * as fs from 'fs';

const UserType = genTsType(
    { user: 'Alice', friends: [{ user: 'Bob', since: new Date() }] },
    { format: true },
  );
const code = `export type User = ${UserType};`
fs.writeFileSync('types.ts', code);

Above example generate into:

export type User = {
  user: string;
  friends: Array<{
    user: string;
    since: Date;
  }>;
}

Features

Supported features

• primitive types
  • string
  • number
  • boolean
  • bigint
  • Date
  • symbol (not specific)
• Array (single-type / union-type)
• Object (strict-type / optional-type)
• named custom type

Todo features

• Tuple (specific-type array) (e.g. [number, string, string])
• specific symbol / string / number
• Enum