Introduces a utility function to load optional scripts such as callstats.io.

JitsiMeetJS.js

@@ -9,6 +9,7 @@ var Logger = require("jitsi-meet-logger");
 var RTC = require("./modules/RTC/RTC");
 var Statistics = require("./modules/statistics/statistics");
 var Resolutions = require("./service/RTC/Resolutions");
+var ScriptUtil = require("./modules/util/ScriptUtil");
 
 function getLowerResolution(resolution) {
     if(!Resolutions[resolution])
@@ -128,7 +129,15 @@ var LibJitsiMeet = {
     },
     enumerateDevices: function (callback) {
         RTC.enumerateDevices(callback);
-    }
+    },
+
+    /**
+     * Represents a hub/namespace for utility functionality which may be of
+     * interest to LibJitsiMeet clients.
+     */
+    util: {
+        ScriptUtil: ScriptUtil,
+    },
 };
 
 //Setups the promise object.

modules/statistics/statistics.js

@@ -4,6 +4,7 @@ var RTPStats = require("./RTPStatsCollector.js");
 var EventEmitter = require("events");
 var StatisticsEvents = require("../../service/statistics/Events");
 var CallStats = require("./CallStats");
+var ScriptUtil = require('../util/ScriptUtil');
 
 // Since callstats.io is a third party, we cannot guarantee the quality of
 // their service. More specifically, their server may take noticeably long
@@ -13,15 +14,10 @@ var CallStats = require("./CallStats");
 // start downloading their API as soon as possible and (2) do the
 // downloading asynchronously.
 function loadCallStatsAPI() {
-    (function (d, src) {
-        var elementName = 'script';
-        var newScript = d.createElement(elementName);
-        var referenceNode = d.getElementsByTagName(elementName)[0];
-
-        newScript.async = true;
-        newScript.src = src;
-        referenceNode.parentNode.insertBefore(newScript, referenceNode);
-    })(document, 'https://api.callstats.io/static/callstats.min.js');
+    ScriptUtil.loadScript(
+            'https://api.callstats.io/static/callstats.min.js',
+            /* async */ true,
+            /* prepend */ true);
     // FIXME At the time of this writing, we hope that the callstats.io API will
     // have loaded by the time we needed it (i.e. CallStats.init is invoked).
 }

modules/util/ScriptUtil.js

@@ -0,0 +1,32 @@
+/**
+ * Implements utility functions which facilitate the dealing with scripts such
+ * as the download and execution of a JavaScript file.
+ */
+var ScriptUtil = {
+    /**
+     * Loads a script from a specific source.
+     *
+     * @param src the source from the which the script is to be (down)loaded
+     * @param async true to asynchronously load the script or false to
+     * synchronously load the script
+     * @param prepend true to schedule the loading of the script as soon as
+     * possible or false to schedule the loading of the script at the end of the
+     * scripts known at the time
+     */
+    loadScript: function (src, async, prepend) {
+        var d = document;
+        var tagName = 'script';
+        var script = d.createElement(tagName);
+        var referenceNode = d.getElementsByTagName(tagName)[0];
+
+        script.async = async;
+        script.src = src;
+        if (prepend) {
+            referenceNode.parentNode.insertBefore(script, referenceNode);
+        } else {
+            referenceNode.parentNode.appendChild(script);
+        }
+    },
+};
+
+module.exports = ScriptUtil;