Open Websocket into Node JS server

gistfile1.txt

require('dotenv').config();
var http = require('http');
var https = require('https');
var fs = require('fs');
const WebSocket = require('ws');
Tail = require('tail').Tail;

var privateKey  = fs.readFileSync('./key.pem', 'utf8');
var certificate = fs.readFileSync('./cert.pem', 'utf8');

var credentials = {key: privateKey, cert: certificate};
var express = require('express');
var app = express();
var certpass = process.env.ENV_CERTPASS;

var options = {
  key: privateKey,
  cert: certificate,
  passphrase: certpass
};

var server = https.createServer(options, function (req, res) {
  res.writeHead(200);
  res.end("hello world\n");
});

const wss = new WebSocket.Server({ server });

wss.on('connection', function connection(ws, req) {

  const ip = req.connection.remoteAddress;
  console.log('client ip'+ip);

ws.on('message', function incoming(message) {
    console.log('received: %s', message);
  });

  ws.send('something your ip '+ip);
});

server.listen(443);