A queue of promises that for the given url will wait for 3 seconds and then upload it to gfycat

DelayAndUploadQueue.js

var uploadQueue
var addGifToUploadQueueWithDelay = (url) => {

  var delayAndUpload = () => {
    return delay().then(uploadGifToGfycat.bind(null, url));
  }

  //Queue is either empty or finished
  if(!uploadQueue || uploadQueue.isFulfilled()){
    uploadQueue = delayAndUpload();
  }
  else {
    uploadQueue = uploadQueue.then(delayAndUpload);
  }

  return uploadQueue;
}

var DELAY = 3000;
var delay = () => new Promise ((resolve) =>
{
  setTimeout(resolve, DELAY);
});