I have created a small library in JS that do some analytics for our customers.
So far, we are including it like the following near the </body>
tag :
<script type="text/javascript" src="https://cdn.myapp.net/main.min.js"></script>
<script type="text/javascript">
MyLib.init("idofthecustomer");
</script>
But apparently, it's not running on some browsers. I have looked other analytics libraries and they are including their scripts in multiple differents ways.
Heap :
<script type="text/javascript">
window.heap=window.heap||[],heap.load=function(e,t){window.heap.appid=e,window.heap.config=t=t||{};var r=t.forceSSL||"https:"===document.location.protocol,a=document.createElement("script");a.type="text/javascript",a.async=!0,a.src=(r?"https:":"http:")+"//cdn.heapanalytics.com/js/heap-"+e+".js";var n=document.getElementsByTagName("script")[0];n.parentNode.insertBefore(a,n);for(var o=function(e){return function(){heap.push([e].concat(Array.prototype.slice.call(arguments,0)))}},p=["addEventProperties","addUserProperties","clearEventProperties","identify","removeEventProperty","setEventProperties","track","unsetEventProperty"],c=0;c<p.length;c++)heap[p[c]]=o(p[c])};
heap.load("YOUR_APP_ID");
</script>
GoogleAnalytics :
<!-- Google Analytics -->
<script>
(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,document,'script','https://www.google-analytics.com/analytics.js','ga');
ga('create', 'UA-XXXXX-Y', 'auto');
ga('send', 'pageview');
</script>
<!-- End Google Analytics -->
Why are they doing such thing? Can you explain me what the goal of this?
In another way, how can we be sure that our script will be loaded and run?
Thanks for your answers !