Promises with Bluebird.

bluebird_promise.js

var Promise = require('bluebird');

var async = function (input) {
  return new Promise(function (resolve, reject) {
    var data = input + ' Whatever.';
    // call the async process here
    setTimeout(function(){
      // send the result when it arrives
      resolve(data);
    }, 100);
  });
};

async("Hello.")
  .then(function (data) {
    console.log(data);
  });