promise-every

Currently javascript does not have a Promise.every() function, so here it is.

1. You have an iterable of Promises.

2. You want to do something when they are all done.

3. You want all the data.

Code

Promise.every = require('every-promise');
Promise.every(ARRAY_OF_PROMISES, function(finished) {
  console.log(finished) // array of finished promises
});

Thats it!

If you want to access just the resolved or rejected promises the callback is passed three parameteres finished, resolved, rejected. In that order, finished will contain both resolved and rejected promises in the order you provided them in.

Instalation

npm install every-promise

You can also just copypaste this into your code:

Promise.every = function(promises, callback) {
  var len;
  const preserved = new Array((len = promises.length));
  const resolved = [], rejected = [];
  (function recurs(found){
    promises[found].then(good => {
      preserved[found] = resolved.push(good) && good;
      if(++found === len) callback(preserved, resolved, rejected);
      else recurs(found)
    }, bad => {
      preserved[found] = rejected.push(bad) && bad;
      if(++found === len) callback(preserved, resolved, rejected);
      else recurs(found)
    })
  })(0)
};

Or useing the traditional .then().catch().

Promise.every = function(promises, callback) {
  var len;
  const preserved = new Array((len = promises.length));
  const resolved = [], rejected = [];
  (function recurs(found){
    promises[found].then(good => {
      preserved[found] = good;
      resolved.push(good);
      if(++found === len) callback(preserved, resolved, rejected);
      else recurs(found)
    }).catch(bad => {
      preserved[found] = bad;
      rejected.push(bad)
      if(++found === len) callback(preserved, resolved, rejected);
      else recurs(found)
   })
  })(0)
};

Dependencies

None.