Backbone patch to defer update method requests when new create requests are not complete on a model

gistfile1.js

// Queue of Backbone.Model save()s so that we don't issue multiple POSTs while waiting for
// the first one to come back. The first save() will always POST and the second will always PUT now.
// https://github.com/documentcloud/backbone/issues/345
// https://gist.github.com/1037984 and https://gist.github.com/gists/3148064
(function() {
  function proxyAjaxEvent(event, options, dit) {
    var eventCallback = options[event];
    options[event] = function() {
      // check if callback for event exists and if so pass on request
      if (eventCallback) { eventCallback(arguments) }
      dit.processQueue(); // move onto next save request in the queue
    }
  }
  Backbone.Model.prototype._save = Backbone.Model.prototype.save;
  Backbone.Model.prototype.save = function( attrs, options ) {
    if (!options) { options = {}; }
    if (this.saving) {
      this.saveQueue = this.saveQueue || new Array();
      this.saveQueue.push({ attrs: _.extend({}, this.attributes, attrs), options: options });
    } else {
      this.saving = true;
      proxyAjaxEvent('success', options, this);
      proxyAjaxEvent('error', options, this);
      Backbone.Model.prototype._save.call( this, attrs, options );
    }
  }
  Backbone.Model.prototype.processQueue = function() {
    if (this.saveQueue && this.saveQueue.length) {
      var saveArgs = this.saveQueue.shift();
      proxyAjaxEvent('success', saveArgs.options, this);
      proxyAjaxEvent('error', saveArgs.options, this);
      Backbone.Model.prototype._save.call( this, saveArgs.attrs, saveArgs.options );
    } else {
      this.saving = false;
    }
  }
})();