index.js

/* npm install promise */
const Promise = require('promise');

function within(time) {
  return new Promise(function (fulfill) {
    setTimeout(fulfill, time);
  });
}

function timeout(promise, milliseconds) {
  return Promise.race([promise, within(milliseconds).then(function () {
    throw new Error(`Operation timed out after ${milliseconds}ms`);
  })]);
}

function slowNetworkRequest() {
  return new Promise( (fulfill) => {
    const data = { name: 'Ryan Cromwell' };

    setTimeout( () => { fulfill(data) }, 5000 );
  });
}

/* Passes because we wait 5.5 seconds */
timeout(slowNetworkRequest(), 5500)
  .then( data => console.log(`Name: ${data.name}`) )
  .catch( err => console.log(err) );

/* Fails because we only wait 2.5 seconds */
timeout(slowNetworkRequest(), 2500)
  .then( data => console.log(`Name: ${data.name}`) )
  .catch( err => console.log(err) );