node-callback-adapter

node callback adapter decorator

This is a function/method decorator which is when applied to a function which returns a promise makes it to handle optionally passed Node-style callback as last argument.

As decorators are a part of future ES7 standard they can only be used with transpilers such as Babel.

Installation:

% npm install node-callback-adapter

Example usage as a method decorator:

import adapt from 'node-callback-adapter'

class Component {

  @adapt
  add(x, y) {
    return Promise.resolve(x + y)
  }
}

let component = new Component()

// call without callback and get a promise back
component.add(2, 2).then(four => console.log(four))

// call with a callback
component.add(2, 2, function(err, four) {
  console.log(four)
})

Example usage as a function decorator:

import {adaptFunction} from 'node-callback-adapter'

let add = adaptFunction(function add(x, y) {
  return Promise.resolve(x + y)
})

// call without callback and get a promise back
add(2, 2).then(four => console.log(four))

// call with a callback
add(2, 2, function(err, four) {
  console.log(four)
})