serverconnection.onmessage=gotMessageFromServer never called after createOffer - webrtc

Question

I'm trying to connect to a browser for video chat using WebRTC and websockets.
I'm able to createoffer, get the ice candidates but the function (where I expect a remote stream response) serverconnection.onmessage is never called.
in my index.html
function pageReady() {
localVideo = document.getElementById("localVideo");
remoteVideo = document.getElementById("remoteVideo");
serverConnection = new WebSocket('ws://localhost:3434');
serverConnection.onmessage = gotMessageFromServer;
var constraints = {
video: true,
audio: true,
};
if (navigator.getUserMedia) {
navigator.getUserMedia(constraints, getUserMediaSuccess, getUserMediaError);
} else {
alert('Your browser does not support getUserMedia API');
}
}
function start(isCaller) {
peerConnection = new RTCPeerConnection(peerConnectionConfig, optional);
console.log('the peer connection is', peerConnection);
peerConnection.onicecandidate = gotIceCandidate;
peerConnection.onaddstream = gotRemoteStream;
peerConnection.addStream(localStream);
if (isCaller)
peerConnection.createOffer(gotDescription, createOfferError);
}
function gotMessageFromServer(message) {
console.log('message is', json);
if (!peerConnection) start(false);
var signal = JSON.parse(message.data);
if (signal.sdp) {
console.log('message is signal.sdp', signal.sdp);
peerConnection.setRemoteDescription(new RTCSessionDescription(signal.sdp), function () {
peerConnection.createAnswer(gotDescription, createAnswerError);
});
} else if (signal.ice) {
console.log('message is signal.ice', signal.ice);
peerConnection.addIceCandidate(new RTCIceCandidate(signal.ice));
}
}
server.js
var WebSocketServer = require('ws').Server;
var wss = new WebSocketServer({ noServer: true });
var http = require('http'),
fs = require('fs');
fs.readFile('../index.html', function (err, html) {
if (err) {
throw err;
}
var server = http.createServer(function (request, response) {
response.writeHeader(200, { "Content-Type": "text/html" });
response.write(html);
response.end();
})
server.listen(3434);
server.on('upgrade', function (req, socket, head) {
wss.handleUpgrade(req, socket, head, function (client) {
});
});
wss.on('connection', function connection(ws) {
ws.on('message', function incoming(message) {
console.log('received: %s', message);
});
ws.send(message);
});
});