async-google-ads.js

// Highly experimental async google ads.
propublica.views.googleAds = propublica.Deferrable.extend({
  cssClass: "ad",
  init : function(){
    this._super();
  },
  
  render : function(){
    // Add google attributes
    var accepted = "author,scope,project,type".split(",");
    $('meta').each(function(){
      var el = $(this);
      var name = el.attr('name');
      if(_.include(accepted, name)){
        _.each(el.attr('content').split(','), function(attr){
          if(attr.replace(/\s*/g, "").length > 0) GA_googleAddAttr(name, attr.replace(/[^\w\s]+/g, "").replace(/\s+/g, "_"));
        });
      }
    });
    // Setup the google slots
    this.el.each(function(){
      try{
      GA_googleAddSlot("ca-pub-7566226630144794", JSON.parse($(this).attr("data-ad"))["slot"]);
      } catch(e){ return; }
    });
    // Fetch the ads
    GA_googleFetchAds();
    
    // We need a count so we can start the queue after we're done
    this.length = this.el.length;
    var self = this;
    // google ads should be the last in the queue because they're amazingly messed up
    // here be dragons
    propublica.app.writeQueue.add(_.bind(self.adify, self));
  },
  
  // We'll use a **document.write** proxy to write each of the ads to the document, it's
  // super dicey, but hopefully the function queue will protect the write calls.
  adify : function(){
    propublica.app.writeQueue.stop();
    var _write = document.write;
    var _cb = window.GA_googleSetAdContentsBySlotForSync;
    var self = this;
    window.GA_googleSetAdContentsBySlotForSync = function(garbage){
      document.write = function(str){
        var el = $(self.query().string + '.' + _.keys(garbage)[0]);
        if(/script/.test(str)) {
          $('script').eq(0).before(str);
        } else {
          $(str).appendTo(el);
        }
      };
      _cb(garbage);
      // We want to make sure the function queue starts and that document write is restored
      // when we've placed the last ad.
      self.length--;
      if(!self.length) {
        document.write = _write;
        propublica.app.writeQueue.start(); // We want to ensure that we start the queue up again
      }
    };
    this.el.each(function(){
      var el = $(this);
      self.insertAd(el);
    });
  },
  
  // This is called through the asyncQueue so that we can be sure that the writes are
  // protected. We're proxying **document.write** in here so it's the danger zone.
  insertAd : function(el){
    try{
      var slot_id = JSON.parse(el.attr("data-ad"))["slot"];
    } catch(e){ return; }
    el.addClass(slot_id);
    document.write = function(str){
      $('script').eq(0).before($(str).attr({type:'text/javascript'}));
    };
    GA_googleFillSlot(slot_id);
  }
});