Example of usage Promise.all

Promise.all.js

var getPromise = (value, delay) => {
  return new Promise(resolve => {
    setTimeout(() => resolve(value), delay);
  });
};

var promise1 = getPromise('value-1', 150);
var promise2 = getPromise('value-2', 250);
var promise3 = getPromise('value-3', 50);

var promise = Promise.all([promise1, promise2, promise3]);
promise
.then(([result1, result2, result3]) => {  
  // I prefer to use in such cases 
  // es6 destructurnig parameters.
  console.log('result of promise1:', result1); 
  console.log('result of promise2:', result2);
  console.log('result of promise3:', result3);
})
.catch(error => {
  console.log('error', error);
});

// Will be printed after some delay:
// result of promise1: value-1
// result of promise2: value-2
// result of promise3: value-3