Async Queuer

gistfile1.txt

function asyncFunction(){
  var deferred = Promise.defer();
  
  setTimeout(function(){
    console.log('ping');
    deferred.resolve();  
  },3000);
  
  return deferred.promise;
}

function AsyncQueuer(){
  var queue = [],
      running = false;
  
  function runQueue(){
    var first = queue.shift();
    
    running = true;
    
    if (first) {
      first.promisable.apply(first.context).then(function() {
        first.deferral.resolve();
        runQueue();
      }, 
      function() {
        first.deferral.reject();
        runQueue();
      });
    } else {
      running = false;
    }
  }
  
  return {
    add: function(promisable, context) {
      var deferred = Promise.defer();
      
      queue.push({
        promisable: promisable,
        deferral: deferred,
        context: context || window
      });
      
      if (!running) {
        runQueue();
      }
      
      return deferred;
    }
  };
}

var asyncQueuer = new AsyncQueuer();

asyncQueuer.add(asyncFunction);
asyncQueuer.add(asyncFunction);
asyncQueuer.add(asyncFunction);