Fixing #38, and may be #39

Channel presence in "socket.io over node.js" can be detected like this:

function testChannelPresence(channel) {
var socket = io.connect('/');

socket.on('presence', function (isChannelPresent) {
console.log('is channel present', isChannelPresent);
if (!isChannelPresent) playRoleOfSessionInitiator();
});

socket.emit('presence', channel);
}
testChannelPresence('default-channel');

Demo: http://webrtc-signaling.jit.su/RTCMultiConnection

Socket.io over Node.js source code:

https://github.com/muaz-khan/WebRTC-Experiment/tree/master/socketio-over-nodejs

DataChannel/DataChannel.js

@@ -485,7 +485,7 @@
             self.sockets = self.sockets.swap();
         }
 
-        window.onunload = function () {
+        window.onbeforeunload = function () {
             leaveChannels();
         };
 

RTCMultiConnection/RTCMultiConnection-v1.2.js

@@ -993,9 +993,13 @@
 
             var that = this;
 
-            window.onunload = function () {
+            window.onbeforeunload = function () {
                 leaveARoom();
             };
+
+			window.onkeyup = function (e) {
+                if (e.keyCode == 116) leaveARoom();
+            };
 
             (function () {
                     var anchors = document.querySelectorAll('a'),

RTCMultiConnection/RTCMultiConnection-v1.3.js

@@ -621,7 +621,7 @@
                 sockets = sockets.swap();
             }
 
-            window.onunload = function () {
+            window.onbeforeunload = function () {
                 leaveARoom();
             };
 
@@ -1068,7 +1068,7 @@
             bandwidth = options.bandwidth;
 
             function setBandwidth(sdp) {
-                if(bandwidth.audio == 50 && bandwidth.video == 256) return sdp;
+                //if(bandwidth.audio == 50 && bandwidth.video == 256) return sdp;
                 sdp = sdp.replace(/a=mid:audio\r\n/g, 'a=mid:audio\r\nb=AS:' + (bandwidth.audio || 50) + '\r\n');
                 sdp = sdp.replace(/a=mid:video\r\n/g, 'a=mid:video\r\nb=AS:' + (bandwidth.video || 256) + '\r\n');
                 return sdp;

socketio-over-nodejs/webrtc-signaling/signaler.js

@@ -1,75 +1,105 @@
 /*  MIT License: https://webrtc-experiment.appspot.com/licence/ -- https://github.com/muaz-khan */
 
-// var port = 80; // use port:80 for non-localhost tests
-var port = 8888; // use port:8888 for localhost tests
-
+var port = 8888;
+// use port:80 for non-localhost (i.e. real) web servers
 var app = require('express')(),
-    server = require('http').createServer(app),
-    io = require('socket.io').listen(server);
+server = require('http').createServer(app),
+io = require('socket.io').listen(server);
 
 server.listen(port);
 
+/* -------------- for presence detection! -------------- */
+
+var channels = {};
+
 /* -------------- <socket.io> -------------- */
 
-io.sockets.on('connection', function (socket) {
-    if (!io.connected) io.connected = true;
+io.sockets.on('connection', function(socket) {
+    var initiatorChannel = '';
+    if (!io.connected)
+        io.connected = true;
 
-    socket.on('new-channel', function (data) {
+    socket.on('new-channel', function(data) {
+        channels[data.channel] = data.channel;
         onNewNamespace(data.channel, data.sender);
     });
+
+    socket.on('presence', function(channel) {
+        var isChannelPresent = !!channels[channel];
+        socket.emit('presence', isChannelPresent);
+        if (!isChannelPresent)
+            initiatorChannel = channel;
+    });
+
+    socket.on('disconnect', function(channel) {
+        if (initiatorChannel)
+            channels[initiatorChannel] = null;
+    });
 });
 
 function onNewNamespace(channel, sender) {
-    io.of('/' + channel).on('connection', function (socket) {
+    io.of('/' + channel).on('connection', function(socket) {
         if (io.isConnected) {
             io.isConnected = false;
             socket.emit('connect', true);
         }
 
-        socket.on('message', function (data) {
-            if (data.sender == sender) socket.broadcast.emit('message', data.data);
+        socket.on('message', function(data) {
+            if (data.sender == sender)
+                socket.broadcast.emit('message', data.data);
         });
     });
 }
 
 /* -------------- </socket.io> -------------- */
 
-app.get('/', function (req, res) {
+app.get('/', function(req, res) {
     res.sendfile(__dirname + '/static/video-conferencing/index.html');
 });
 
-app.get('/socketio.js', function (req, res) {
+app.get('/socketio.js', function(req, res) {
     res.setHeader('Content-Type', 'application/javascript');
     res.sendfile(__dirname + '/static/socket.io.js');
 });
 
-app.get('/RTCPeerConnection-v1.5.js', function (req, res) {
+app.get('/RTCPeerConnection-v1.5.js', function(req, res) {
     res.setHeader('Content-Type', 'application/javascript');
     res.sendfile(__dirname + '/static/video-conferencing/RTCPeerConnection-v1.5.js');
 });
 
-app.get('/conference.js', function (req, res) {
+app.get('/conference.js', function(req, res) {
     res.setHeader('Content-Type', 'application/javascript');
     res.sendfile(__dirname + '/static/video-conferencing/conference.js');
 });
 
-app.get('/conference-ui.js', function (req, res) {
+app.get('/conference-ui.js', function(req, res) {
     res.setHeader('Content-Type', 'application/javascript');
     res.sendfile(__dirname + '/static/video-conferencing/conference-ui.js');
 });
 
-// text chat
-app.get('/chat', function (req, res) {
+/* -------------- text chat -------------- */
+app.get('/chat', function(req, res) {
     res.sendfile(__dirname + '/static/text-chat.html');
 });
 
-// following lines aimed to auto-open the browser
+/* -------------- RTCMultiConnection demos -------------- */
+
+app.get('/RTCMultiConnection', function(req, res) {
+    res.sendfile(__dirname + '/static/RTCMultiConnection/index.html');
+});
+
+app.get('/RTCMultiConnection-v1.2.js', function(req, res) {
+    res.setHeader('Content-Type', 'application/javascript');
+    res.sendfile(__dirname + '/static/RTCMultiConnection/RTCMultiConnection-v1.2.js');
+});
+
+// following lines aimed to auto-open the browser instance
 // you can remove them if causing failure
 var childProcess = require('child_process'),
-    openURL = 'http://localhost:' + port + '/';
+openURL = 'http://localhost:' + port + '/';
 
 var chromeURL = 'C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe',
-    firefoxURL = 'c:\\Program Files (x86)\\Mozilla Firefox\\firefox.exe';
+firefoxURL = 'c:\\Program Files (x86)\\Mozilla Firefox\\firefox.exe';
 
 childProcess.spawn(chromeURL, ['-incognito', openURL]);
-//childProcess.spawn(firefoxURL, ['-new-tab', openURL]);
+//childProcess.spawn(firefoxURL, ['-new-tab', openURL]);