Ember.js Google Tag Manager utility

## gtm-util.js
// Google Tag Manager
(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
j=d.createElement(s);j.async=true;j.src=
'//www.googletagmanager.com/gtm.js?id='+i;f.parentNode.insertBefore(j,f);
})(window,document,'script','dataLayer','GTM-ABCDEF');
// End Google Tag Manager

App.GtmUtil = {

  defaultEvent: {
    event: 'trackEvent',
    eventCategory: '',
    eventAction: '',
    eventLabel: '',
    eventValue: ''
  },

  defaultPageView: {
    event: 'vpv',
    virtualPagePath: ''
  },

  createPayload: function (type, o) {
    var data = o || {};
    var defaultPayload = this['default' + type];
    var payload = {};
    Object.keys(defaultPayload).forEach(function (key) {
      payload[key] = data.hasOwnProperty(key) ? data[key] : defaultPayload[key];
    });
    return payload;
  },

  trackEvent: function (o) {
    window.dataLayer.push(this.createPayload('Event', o));
  },

  trackPageView: function (path) {
    window.dataLayer.push(this.createPayload('PageView', { virtualPagePath: path }));
  }
};

## z1_gtm-initializer.js
require('../utils/gtm-util');

Ember.Application.initializer({
  name: 'googleTagManager',

  initialize: function (container, application) {
    var router = container.lookup('router:main');

    router.on('didTransition', function () {
      App.GtmUtil.trackPageView(this.get('url'));
    });
  }
});

## z2_application-route.js
// Sample usage of App.GtmUtil.trackEvent

require('../utils/gtm-util');

App.ApplicationRoute = Ember.Route.extend({

  actions: {

    openModal: function (name, model) {
      App.GtmUtil.trackEvent({ eventCategory: 'Application', eventAction: 'openModal', eventLabel: name });
      this.controllerFor('modal.' + name).set('model', model);
      return this.render('modal/' + name, {
        into: 'application',
        outlet: 'modal'
      });
    },

    closeModal: function () {
      App.GtmUtil.trackEvent({ eventCategory: 'Application', eventAction: 'closeModal' });
      return this.disconnectOutlet({
        outlet: 'modal',
        parentView: 'application'
      });
    }
  }

});