Check if analytics.js is loaded

Question

I have to use a local analytics.js that I serve from my server. I just want to use the local version if necessary - so is there a solution for checking if the call for analy

Answer 1

A particularly elegant solution would be to use RequireJS and leverage its support for fallback paths. I do this on my site to load a stub version of analytics.js if loading GA fails because the visitor uses a privacy tool blocking the request:

http://veithen.github.io/2015/02/14/requirejs-google-analytics.html

Your use case is similar, except that you want to fallback to a complete local copy. You also probably don't want to change all calls to GA as described in that article. If that's the case then you could use a hybrid approach where you only use RequireJS to load analytics.js (Google's version or the local copy), without changing any other code.

Setting this up would involve the following steps:

• Add RequireJS to your site and configure it as follows:

  require.config({
      paths: {
          "ga": [
              "//www.google-analytics.com/analytics",
              "local-copy-of-analytics"
          ]
      }
  });
  

• Use the alternative version of the tracking code, but replace <script async src='//www.google-analytics.com/analytics.js'></script> with the following JavaScript code:

  require(["ga"]);
  

Answer 2

There's a function to track if the library has loaded. From the docs:

ga(function(tracker) {
   var defaultPage = tracker.get('page');
});

The passed in function is executed when the library is loaded, so you could set a variable to keep track of whether or not it has loaded. You'd have to put it on some sort of timer to decide when you want to consider it failed:

var loaded = false;
ga(function() {
   loaded = true;
});

// after one second do something if the library hasn't loaded
setTimeout(function(){
    if (!loaded){
        //do something
    }
},1000);

Answer 3

instead of waiting for a callback, you can easily get it with

if(window.ga && ga.loaded) {
    // yeps... it is loaded!
}

you can easily see this in the Firefox documentation

same trick can be applied if you want to see if the tracker is blocked (by any plugin for example)

if(window.ga && ga.q) {
    // yeps... blocked! >:o
}