Setting up a google analytics service in an angularjs application

analyticsService.js

var myModule = angular.module('myModule', []);
myModule.factory('googleAnalytics', ['$window',  function($window) {  
    // Initialize GA Tracker
    (function (i, s, o, g, r, a, m) {
        i['GoogleAnalyticsObject'] = r;
        i[r] = i[r] || function () {
            (i[r].q = i[r].q || []).push(arguments)
        }, i[r].l = 1 * new Date();
        a = s.createElement(o),
            m = s.getElementsByTagName(o)[0];
        a.async = 1;
        a.src = g;
        m.parentNode.insertBefore(a, m)
    })($window, $window.document, 'script', '//www.google-analytics.com/analytics.js', 'ga');

    $window.ga('create', 'UA-XXXXXXXX-X', 'auto');
  
  return {
      tracker: $window.ga
  }
}]);

app.js

angular.run(['$rootScope', '$location', 'googleAnalytics', 
    function ($rootScope, $location, googleAnalytics) {
        $rootScope.$on('$routeChangeSuccess',
            function(event) {
                googleAnalytics.tracker('send', 'pageview', { page: $location.path() });
            });
    });
]);