Help! Run ws on the same port as a http Express?

[m2kar]

How to run ws on the same port as a http Express?

I tried the example express-session-parse given by ws (link), and replace the const { WebSocketServer } = require('ws'); to const WebSocketServer = require('rpc-websockets').Server;, and add a hello remote function, but it didn't work. The client has no output, the server output is only Parsing session from request.. .

What need I do?

The source code of server and client are :

server

// server: index.json
'use strict';

const session = require('express-session');
const express = require('express');
const http = require('http');
const uuid = require('uuid');

const  WebSocketServer = require('rpc-websockets').Server;

const app = express();
const map = new Map();

//
// We need the same instance of the session parser in express and
// WebSocket server.
//
const sessionParser = session({
  saveUninitialized: false,
  secret: '$eCuRiTy',
  resave: false
});

//
// Serve static files from the 'public' folder.
//
app.use(express.static('public'));
app.use(sessionParser);

app.post('/login', function (req, res) {
  //
  // "Log in" user and set userId to session.
  //
  const id = uuid.v4();

  console.log(`Updating session for user ${id}`);
  req.session.userId = id;
  res.send({ result: 'OK', message: 'Session updated' });
});

app.delete('/logout', function (request, response) {
  const ws = map.get(request.session.userId);

  console.log('Destroying session');
  request.session.destroy(function () {
    if (ws) ws.close();

    response.send({ result: 'OK', message: 'Session destroyed' });
  });
});

//
// Create an HTTP server.
//
const server = http.createServer(app);

//
// Create a WebSocket server completely detached from the HTTP server.
//
const wss = new WebSocketServer({ clientTracking: false, noServer: true });

server.on('upgrade', function (request, socket, head) {
  console.log('Parsing session from request...');

  sessionParser(request, {}, () => {
    if (!request.session.userId) {
      socket.write('HTTP/1.1 401 Unauthorized\r\n\r\n');
      socket.destroy();
      return;
    }

    console.log('Session is parsed!');

    wss.handleUpgrade(request, socket, head, function (ws) {
      wss.emit('connection', ws, request);
    });
  });
});
wss.on('listening',()=>{
wss.register('hello',({index})=>{
  console.log(index);
  return `index:${index}`;
})

})
wss.on('connection', function (ws, request) {
  const userId = request.session.userId;

  map.set(userId, ws);

  ws.on('message', function (message) {
    //
    // Here we can now use session parameters.
    //
    console.log(`Received message ${message} from user ${userId}`);
  });

  ws.on('close', function () {
    map.delete(userId);
  });
});
//
// Start the server.
//
server.listen(8082, function () {
  console.log('Listening on http://localhost:8082');
});

client

// client: rpc_client.js
const WebSocket = require('rpc-websockets').Client;
// instantiate Client and connect to an RPC server
const ws = new WebSocket('ws://localhost:8082/');
ws.on('open', function () {
    console.log("connected");
    ws.call("hello",{index},).then((ret)=>{
        console.log(ret);
    }).catch(err=>{
        console.trace(err);
    })

});

[jumo-sballing]

Don't know if this helps but I pass the express server straight to the WebsocketServer. This works fine.

//
// Create an HTTP server.
//
const server = http.createServer(app);

//
// Create a WebSocket server and pass the express webserver.
//
const wss = new WebSocketServer({ server });

wss.on('connection', (socket, request) => {
    console.log('ws client connected, ' + socket._id + ', ' + request.url);
});

[mkozjak]

@m2kar A PR with documentation updates with your findings would be much appreciated!