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app.js

@@ -22,14 +22,17 @@ app.configure('production', function() {
   app.use(express.errorHandler());
 });
 
-io.configure(function () { 
-  io.set("transports", ["xhr-polling"]); 
-  io.set("polling duration", 10); 
-});
+// Heroku won't actually allow us to use WebSockets
+// so we have to setup polling instead.
+// https://devcenter.heroku.com/articles/using-socket-io-with-node-js-on-heroku
+// io.configure(function () { 
+//   io.set("transports", ["xhr-polling"]); 
+//   io.set("polling duration", 10); 
+// });
 
 // Routes
 
-var port = process.env.PORT || 5000;
+var port = process.env.PORT || 5000; // Use the port that Heroku provides or default to 5000
 app.listen(port, function() {
   console.log("Express server listening on port %d in %s mode", app.address().port, app.settings.env);
 });
@@ -39,9 +42,9 @@ app.get('/', routes.index);
 var status = "All is well.";
 
 io.sockets.on('connection', function (socket) {
-  socket.emit('status', { status: status });
+  io.sockets.emit('status', { status: status }); // note the use of io.sockets to emit but socket.on to listen
   socket.on('reset', function (data) {
     status = "War is imminent!";
-    socket.emit('status', { status: status });
+    io.sockets.emit('status', { status: status });
   });
 });