Respect doNotTrack setting

js/h5p-x-api-event.js

@@ -191,6 +191,29 @@ H5P.XAPIEvent.prototype.setContext = function (instance) {
  * Set the actor. Email and name will be added automatically.
  */
 H5P.XAPIEvent.prototype.setActor = function () {
+
+  /*
+   * Check for doNotTrack setting by user. Could be placed in h5p.js.
+   * @param {boolean} [strict=true] If True, will assume "do no track" if unset.
+   * @return {boolean} True, if user should not be tracked.
+   */
+  const isDoNotTrackSet = function (strict) {
+    strict = (typeof strict === 'boolean') ? strict : true;
+
+    // User explicitly does not want to be tracked
+    if (window.doNotTrack === '1' || navigator.doNotTrack === 'yes' || navigator.doNotTrack === '1') {
+      return true;
+    }
+
+    // Strict and user/browser did not specify doNotTrack setting
+    if (strict && !(window.doNotTrack || navigator.doNotTrack)) {
+      return true;
+    }
+
+    // Not strict or user explicitly allowed tracking
+    return false;
+  }
+
   if (H5PIntegration.user !== undefined) {
     this.data.statement.actor = {
       'name': H5PIntegration.user.name,
@@ -200,6 +223,11 @@ H5P.XAPIEvent.prototype.setActor = function () {
   }
   else {
     var uuid;
+
+    if (isDoNotTrackSet()) {
+      uuid = 'not-trackable-' + H5P.createUUID();
+    }
+    else {
       try {
         if (localStorage.H5PUserUUID) {
           uuid = localStorage.H5PUserUUID;
@@ -213,6 +241,8 @@ H5P.XAPIEvent.prototype.setActor = function () {
         // LocalStorage and Cookies are probably disabled. Do not track the user.
         uuid = 'not-trackable-' + H5P.createUUID();
       }
+    }
+
     this.data.statement.actor = {
       'account': {
         'name': uuid,