Track javascript errors to google analytics

track-errors.js

(function () {
    'use strict';

    var duringErrorTrack = false;
    var ua = 'UA-XXXXXX-X'

    // don't break old browsers
    if (!window.addEventListener) {
        return;
    }

    window.addEventListener('error', function (e) {
        // Prevent theoretical error handle recursion
        if (duringErrorTrack) {
            return;
        }

        duringErrorTrack = true;

        if (!window.ga) {
            // Load analytics on demand if its not yet available on the page
            (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');
        }

        window.ga('create', ua, 'auto', {'name': 'jsErrors'});

        window.ga('jsErrors.send', 'event', 'DEBUG: js error', 'message:' + e.message, 'location:' + e.filename + ':' + e.lineno + ':' + e.colno);

        duringErrorTrack = false;
    });
}());