Index: lams_learning/web/includes/javascript/learnerPage.js
===================================================================
diff -u -r89f41df2ea71b152595e2497fd3ca690e5464d16 -rd1d25ad3d8e023bd467dda99f615f7fd1b70ef91
--- lams_learning/web/includes/javascript/learnerPage.js	(.../learnerPage.js)	(revision 89f41df2ea71b152595e2497fd3ca690e5464d16)
+++ lams_learning/web/includes/javascript/learnerPage.js	(.../learnerPage.js)	(revision d1d25ad3d8e023bd467dda99f615f7fd1b70ef91)
@@ -82,10 +82,108 @@
                 .css('width', progressBarWidgetValue + '%')
                 .attr('aria-valuenow', progressBarWidgetValue);
             $('#progress-bar-widget-value').text(progressBarWidgetValue + '%');
+
+
+            initCommandWebsocket(result.lessonID);
         }
     });
 }
 
+function initCommandWebsocket(lessonId) {
+    let commandWebsocketInitTime = Date.now(),
+        commandWebsocket = null,
+        commandWebsocketPingTimeout = null,
+        commandWebsocketPingFunc = null,
+        commandWebsocketReconnectAttempts = 0,
+        commandWebsocketHookTrigger = null,
+        commandWebsocketHook = null;
+
+    commandWebsocketPingFunc = function (skipPing) {
+        if (commandWebsocket.readyState == commandWebsocket.CLOSING
+            || commandWebsocket.readyState == commandWebsocket.CLOSED) {
+            return;
+        }
+
+        // check and ping every 3 minutes
+        commandWebsocketPingTimeout = setTimeout(commandWebsocketPingFunc, 3 * 60 * 1000);
+        // initial set up does not send ping
+        if (!skipPing) {
+            commandWebsocket.send("ping");
+        }
+    };
+
+    // it is not an obvious place to init the websocket, but we need lesson ID
+    commandWebsocket = new WebSocket(LAMS_URL .replace('http', 'ws')
+        + 'learning/commandWebsocket?lessonID=' + lessonId);
+
+    commandWebsocket.onclose = function (e) {
+        // check reason and whether the close did not happen immediately after websocket creation
+        // (possible access denied, user logged out?)
+        if (e.code === 1006 &&
+            Date.now() - commandWebsocketInitTime > 1000 &&
+            commandWebsocketReconnectAttempts < 20) {
+            commandWebsocketReconnectAttempts++;
+            // maybe iPad went into sleep mode?
+            // we need this websocket working, so init it again after delay
+            setTimeout(initCommandWebsocket, 3000);
+        }
+    };
+
+    // set up timer for the first time
+    commandWebsocketPingFunc(true);
+
+    // when the server pushes new commands
+    commandWebsocket.onmessage = function (e) {
+        // read JSON object
+        var command = JSON.parse(e.data);
+        if (command.message) {
+            // some tools implement autosave feature
+            // if it is such a tool, trigger it
+            if (command.message === 'autosave') {
+                // the name of this function is same in all tools
+                if (typeof learnerAutosave == 'function') {
+                    learnerAutosave(true);
+                }
+            } else {
+                alert(command.message);
+            }
+        }
+
+        // if learner's currently displayed page has hookTrigger same as in the JSON
+        // then a function also defined on that page will run
+        if (command.hookTrigger && command.hookTrigger == commandWebsocketHookTrigger
+            && typeof commandWebsocketHook === 'function') {
+            commandWebsocketHook(command.hookParams);
+        }
+
+        if (command.redirectURL) {
+            window.location.href = command.redirectURL;
+        }
+
+        if (command.discussion) {
+            var discussionCommand = $('#discussion-sentiment-command');
+            if (discussionCommand.length === 0) {
+                discussionCommand = $('<div />').attr('id', 'discussion-sentiment-command').appendTo('body');
+            }
+            discussionCommand.load(LAMS_URL + "learning/discussionSentiment/" + command.discussion + ".do", {
+                lessonId: lessonId
+            });
+        }
+
+        // reset ping timer
+        clearTimeout(commandWebsocketPingTimeout);
+        commandWebsocketPingFunc(true);
+    };
+
+    // check if there is a running discussion; if so, a websocket command will come to display the widget
+    $.ajax({
+        url: LAMS_URL + "learning/discussionSentiment/checkLearner.do",
+        data: {
+            lessonId: lessonId
+        }
+    });
+}
+
 function toggleProgressBar(forceClose) {
     let pageContent = $('.component-page-wrapper .component-page-content'),
         progressBar = $('.component-page-wrapper .component-sidebar'),
@@ -105,7 +203,7 @@
         progressBar.removeAttr('inert');
         $('.sidebar-toggle-button', progressBar).focus();
 
-        $('body').on('keyup', function (event){
+        $('body').on('keyup', function (event) {
             if (event.key === "Escape") {
                 toggleProgressBar(true);
             }