Create Websocket Secure on a HTTPS web server in express app - node.js

Question

I have a application in express.js. Am unable to create wss on a HTTPS web server.
var fs = require('fs');
var express = require('express');
var app = express();
var cfg = {
ssl: true,
port: 8001,
ssl_key: 'sslcert/ssl.key',
ssl_cert: 'sslcert/ssl.crt'
};
var httpServ = (cfg.ssl) ? require('https') : require('http');
if (cfg.ssl) {
httpsServer = httpServ.createServer({
key: fs.readFileSync(cfg.ssl_key),
cert: fs.readFileSync(cfg.ssl_cert)
}, app)
.listen(cfg.port, function () {
console.log('Magic happening at https://Secure');
});
} else {
httpsServer = httpServ.createServer(app)
.listen(cfg.port, function () {
console.log('Magic happening at http://InSecure');
});
}
var WebSocketServer = require('websocket')
.server;
var wsServer = new WebSocketServer({
httpServer: httpsServer
});
wsServer.on('connection', function connection(ws) {
console.log('Socket Connected');
});
I'm under the impression that passing a reference of the web server to WebSocket, then WebSocket would know the port and SSL capabilities of the server. But every time I get an error in the console
WebSocket connection to 'ws://localhost:8001/?trackme=TUKOCVPAF' failed: Connection closed before receiving a handshake response
How can I create a wss://localhost:8001/?trackme=TUKOCVPAF' when creating the Websocket..??