Pickrr

Contracts in Typescript done right.

Goal

To have a simple contract in typescript that doesn't need an accompanying interface. i.e. The contract itself is the interface.

Installation

npm i --save pickrr

Usage

General usage

import {pick, number, string} from 'pickrr'

// Let's say req.body = {id: '1', name: 'John Doe'}

const data = pick({
  id: number,
  name: string,
}, req.body);

// data now has a signature of {id: number; name: string}
// and a value of {id: 1, name: 'John Doe'}

You can even pass multiple objects

import {pick, number, string, date} from 'pickrr'

const data = pick({
  id: number,
  name: string,
  birthdate: date,
}, req.params, req.body);

// data now has the same signature as the contract itself.

Optional vs required rules

If none of your params are required use the pick function.

const data = pick(
  {
    // optional rules
    id: number,
    name: string,
  }, 
  inputObject1, 
  inputObject2,
  // ... as many other objects to take properties from
);

If all of your params are required use the pickRqr function.

const data = pickRqr(
  {
    // required rules
    id: number,
    name: string,
  }, 
  inputObject1, 
  inputObject2,
  // ... as many other objects to take properties from
);

If some of your params are required use the pick2 function which lets you specify some required + some optional rules.

const data = pick2(
  {
    // required rules
    id: number,
    name: string,
  }, 
  {
    // optional rules
    foo: number,
  }, 
  inputObject1, 
  inputObject2,
  // ... as many other objects to take properties from
);

The trick? Take a look at src/index.ts.