thenifiedly

thenifiedly

Promisifiedly call a callback style function/method with an es6 promise returned.

Install

$ npm install thenifiedly

Usage

import http from 'http';
import thenifiedly from 'thenifiedly';

const callWrite = thenifiedly.callMethodFactory('write');

http.createServer(async (req, res) => {
  const ghRes = await thenifiedly.call(
    http.get,
    'https://github.com'
  );
  await callWrite(res, `GitHub is ${
    ghRes.statusCode < 300 ? 'ok': 'down'
  }! `);
  ghRes.destroy();

  await callMethod('end', res, 'Bye!');
  console.log('Response Ended!');
});

This is especially useful when the function/instance is from the parameters or returned dynamically. Thus you don't need to wrap it every time before use, and might gain small performance enhancement from it. Check benchmark.

API

call: (fn, [...args]) ⇒ Promise

Call a callback style function with postceding arguments, return a promise.

fn Function

The function to be called.

args any[]

Arguments to be passed to fn, except the most postceded callback.

async () => {
  const statOfMe = await thenifiedly.call(fs.stat, '/tmp/me');
}

callMethod: (method, instance, [...args]) ⇒ Promise

method string|Symbol

The method name to be called on the instance object.

instance Object

The object contains the method to be called.

args any[]

Arguments to be passed to method, except the most postceded callback.

async () => {
  const worker = child_process.fork('some.js');
  await thenifiedly.callMethod('send', worker, { do: 'a job' });
}

callMethodFactory: (method) ⇒ (instance, [...args]) ⇒ Promise

Make a method calling function with the method name specified.

method string|Symbol

The method name to be called on the instance object.

instance Object

The object contains the method to be called.

args any[]

Arguments to be passed to method, except the postceded callback function.

const callEnd = thenifiedly.callMethodFactory('end');

http.createServer(async (req, res) => {
  await callEnd(res, 'Hello world!');
  console.log('Finished!');
});

Benchmark

Tested with node.js v10.8.0, check ./benchmarks for details.

### Test promisify function every time:
  util.promisify x 115,690 ops/sec ±2.69% (81 runs sampled)
  thenify x 226,758 ops/sec ±2.24% (82 runs sampled)
  es6-promisify x 1,433,982 ops/sec ±1.04% (80 runs sampled)
  pify x 1,969,359 ops/sec ±2.96% (77 runs sampled)
  thenifiedly.call x 3,704,139 ops/sec ±0.89% (84 runs sampled)

### Test promisify function once:
  util.promisify x 3,117,345 ops/sec ±0.86% (85 runs sampled)
  thenify x 3,529,109 ops/sec ±2.95% (83 runs sampled)
  es6-promisify x 1,559,947 ops/sec ±0.92% (83 runs sampled)
  pify x 3,164,405 ops/sec ±2.46% (82 runs sampled)
  thenifiedly.call x 3,724,577 ops/sec ±0.73% (83 runs sampled)

### Test promisify method every time:
  thenify-all x 204,321 ops/sec ±1.19% (82 runs sampled)
  pify x 1,494,615 ops/sec ±2.39% (82 runs sampled)
  thenifiedly.callMethod x 3,683,058 ops/sec ±0.75% (84 runs sampled)
  thenifiedly.callMethodFactory x 3,657,715 ops/sec ±2.42% (84 runs sampled)

### Test promisify method once:
  thenify-all x 3,591,625 ops/sec ±0.80% (86 runs sampled)
  pify x 3,628,348 ops/sec ±0.98% (80 runs sampled)
  thenifiedly.callMethod x 3,626,803 ops/sec ±2.34% (83 runs sampled)
  thenifiedly.callMethodFactory x 3,738,145 ops/sec ±0.98% (84 runs sampled)

License

MIT