node.js, socket.io with SSL

I'm trying to get socket.io running with my SSL certificate however, it will not connect.

I based my code off the chat example:

var https = require('https');
var fs = require('fs');
/**
 * Bootstrap app.
 */
var sys = require('sys')
require.paths.unshift(__dirname + '/../../lib/');

/**
* Module dependencies.
*/

var express = require('express')
  , stylus = require('stylus')
  , nib = require('nib')
  , sio = require('socket.io');

/**
 * App.
 */
var privateKey = fs.readFileSync('../key').toString();
var certificate = fs.readFileSync('../crt').toString();
var ca = fs.readFileSync('../intermediate.crt').toString();

var app = express.createServer({key:privateKey,cert:certificate,ca:ca });


/**
 * App configuration.
 */

...

/**
 * App routes.
 */

app.get('/', function (req, res) {
  res.render('index', { layout: false });
});

/**
 * App listen.
 */

app.listen(443, function () {
  var addr = app.address();
  console.log('   app listening on http://' + addr.address + ':' + addr.port);
});

/**
 * Socket.IO server (single process only)
 */

var io = sio.listen(app,{key:privateKey,cert:certificate,ca:ca});
...

If I remove the SSL code it runs fine, however with it I get a request to http://domain.com/socket.io/1/?t=1309967919512

Note it's not trying https, which causes it to fail.

I'm testing on chrome, since it is the target browser for this application.

I apologize if this is a simple question, I'm a node/socket.io newbie.

Thanks!

Use a secure URL for your initial connection, i.e. instead of "http://" use "https://". If the WebSocket transport is chosen, then Socket.IO should automatically use "wss://" (SSL) for the WebSocket connection too.

Update:

You can also try creating the connection using the 'secure' option:

var socket = io.connect('https://localhost', {secure: true});

The following is how I set up to set it up with express:

    var app = require('express')();
    var https = require('https');
    var fs = require( 'fs' );
    var io = require('socket.io')(server);

    var options = {
        key: fs.readFileSync('./test_key.key'),
        cert: fs.readFileSync('./test_cert.crt'),
        ca: fs.readFileSync('./test_ca.crt'),

        requestCert: false,
        rejectUnauthorized: false
    }

    var server = https.createServer(options, app);
    server.listen(8080);
    

    
    io.sockets.on('connection', function (socket) {
    	// code goes here...
    });
    
    app.get("/", function(request, response){
    	// code goes here...
    })
   

Update : for those using lets encrypt use this

var server = https.createServer({ 
                key: fs.readFileSync('privkey.pem'),
                cert: fs.readFileSync('fullchain.pem') 
             }, app);

On the same note, if your server supports both http and https you can connect using:

var socket = io.connect('//localhost');

to auto detect the browser scheme and connect using http/https accordingly. when in https, the transport will be secured by default, as connecting using

var socket = io.connect('https://localhost');

will use secure web sockets - wss:// (the {secure: true} is redundant).

for more information on how to serve both http and https easily using the same node server check out this answer.

If your server certificated file is not trusted, (for example, you may generate the keystore by yourself with keytool command in java), you should add the extra option rejectUnauthorized

var socket = io.connect('https://localhost', {rejectUnauthorized: false});

Depending on your needs, you could allow both secure and unsecure connections and still only use one Socket.io instance.

You simply have to instanciate two servers, one for HTTP and one for HTTPS, then attach those servers to the Socket.io instance.

Server side :

// needed to read certificates from disk
const fs          = require( "fs"    );

// Servers with and without SSL
const http        = require( "http"  )
const https       = require( "https" );
const httpPort    = 3333;
const httpsPort   = 3334;
const httpServer  = http.createServer();
const httpsServer = https.createServer({
    "key" : fs.readFileSync( "yourcert.key" ),
    "cert": fs.readFileSync( "yourcert.crt" ),
    "ca"  : fs.readFileSync( "yourca.crt"   )
});
httpServer.listen( httpPort, function() {
    console.log(  `Listening HTTP on ${httpPort}` );
});
httpsServer.listen( httpsPort, function() {
    console.log(  `Listening HTTPS on ${httpsPort}` );
});

// Socket.io
const ioServer = require( "socket.io" );
const io       = new ioServer();
io.attach( httpServer  );
io.attach( httpsServer );

io.on( "connection", function( socket ) {

    console.log( "user connected" );
    // ... your code

});

Client side :

var url    = "//example.com:" + ( window.location.protocol == "https:" ? "3334" : "3333" );
var socket = io( url, {
    // set to false only if you use self-signed certificate !
    "rejectUnauthorized": true
});
socket.on( "connect", function( e ) {
    console.log( "connect", e );
});

If your NodeJS server is different from your Web server, you will maybe need to set some CORS headers. So in the server side, replace:

const httpServer  = http.createServer();
const httpsServer = https.createServer({
    "key" : fs.readFileSync( "yourcert.key" ),
    "cert": fs.readFileSync( "yourcert.crt" ),
    "ca"  : fs.readFileSync( "yourca.crt"   )
});

With:

const CORS_fn = (req, res) => {
    res.setHeader( "Access-Control-Allow-Origin"     , "*"    );
    res.setHeader( "Access-Control-Allow-Credentials", "true" );
    res.setHeader( "Access-Control-Allow-Methods"    , "*"    );
    res.setHeader( "Access-Control-Allow-Headers"    , "*"    );
    if ( req.method === "OPTIONS" ) {
        res.writeHead(200);
        res.end();
        return;
    }
};
const httpServer  = http.createServer( CORS_fn );
const httpsServer = https.createServer({
        "key" : fs.readFileSync( "yourcert.key" ),
        "cert": fs.readFileSync( "yourcert.crt" ),
        "ca"  : fs.readFileSync( "yourca.crt"   )
}, CORS_fn );

And of course add/remove headers and set the values of the headers according to your needs.

check this.configuration..

app = module.exports = express();
var httpsOptions = { key: fs.readFileSync('certificates/server.key'), cert: fs.readFileSync('certificates/final.crt') };		
var secureServer = require('https').createServer(httpsOptions, app);
io = module.exports = require('socket.io').listen(secureServer,{pingTimeout: 7000, pingInterval: 10000});
io.set("transports", ["xhr-polling","websocket","polling", "htmlfile"]);
secureServer.listen(3000);

Server-side:

import http from 'http';
import https from 'https';
import SocketIO, { Socket } from 'socket.io';
import fs from 'fs';
import path from 'path';

import { logger } from '../../utils';

const port: number = 3001;

const server: https.Server = https.createServer(
  {
    cert: fs.readFileSync(path.resolve(__dirname, '../../../ssl/cert.pem')),
    key: fs.readFileSync(path.resolve(__dirname, '../../../ssl/key.pem'))
  },
  (req: http.IncomingMessage, res: http.ServerResponse) => {
    logger.info(`request.url: ${req.url}`);

    let filePath = '.' + req.url;
    if (filePath === './') {
      filePath = path.resolve(__dirname, './index.html');
    }

    const extname = String(path.extname(filePath)).toLowerCase();
    const mimeTypes = {
      '.html': 'text/html',
      '.js': 'text/javascript',
      '.json': 'application/json'
    };

    const contentType = mimeTypes[extname] || 'application/octet-stream';

    fs.readFile(filePath, (error: NodeJS.ErrnoException, content: Buffer) => {
      if (error) {
        res.writeHead(500);
        return res.end(error.message);
      }
      res.writeHead(200, { 'Content-Type': contentType });
      res.end(content, 'utf-8');
    });
  }
);

const io: SocketIO.Server = SocketIO(server);

io.on('connection', (socket: Socket) => {
  socket.emit('news', { hello: 'world' });
  socket.on('updateTemplate', data => {
    logger.info(data);
    socket.emit('updateTemplate', { random: data });
  });
});

server.listen(port, () => {
  logger.info(`Https server is listening on https://localhost:${port}`);
});

Client-side:

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Websocket Secure Connection</title>
</head>

<body>
  <div>
    <button id='btn'>Send Message</button>
    <ul id='messages'></ul>
  </div>
  <script src='../../../node_modules/socket.io-client/dist/socket.io.js'></script>
  <script>
    window.onload = function onload() {
      const socket = io('https://localhost:3001');
      socket.on('news', function (data) {
        console.log(data);
      });

      socket.on('updateTemplate', function onUpdateTemplate(data) {
        console.log(data)
        createMessage(JSON.stringify(data));
      });
      const $btn = document.getElementById('btn');
      const $messages = document.getElementById('messages');

      function sendMessage() {
        socket.emit('updateTemplate', Math.random());
      }

      function createMessage(msg) {
        const $li = document.createElement('li');
        $li.textContent = msg;
        $messages.appendChild($li);
      }

      $btn.addEventListener('click', sendMessage);
    }
  </script>
</body>

</html>

For enterprise applications it should be noted that you should not be handling https in your code. It should be auto upgraded via IIS or nginx. The app shouldn't know about what protocols are used.

In case someone need a shorter form

var fs = require('fs');
var https = require('https');

var express = require('express');
var app = express();

var options = {
  key: fs.readFileSync('/path-to/ssl.key'),
  cert: fs.readFileSync('/path-to/ssl.cert')
};

var server = https.createServer(options, app);
var io = require('socket.io')(server);

This is my nginx config file and iosocket code. Server(express) is listening on port 9191. It works well: nginx config file:

server {
    listen       443 ssl;
    server_name  localhost;
    root   /usr/share/nginx/html/rdist;

    location /user/ {
        proxy_pass   http://localhost:9191;
    }
    location /api/ {
        proxy_pass   http://localhost:9191;
    }
    location /auth/ {
        proxy_pass   http://localhost:9191;
    }

    location / {
        index  index.html index.htm;
        if (!-e $request_filename){
          rewrite ^(.*)$ /index.html break;
        }
    }
    location /socket.io/ {
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_pass   http://localhost:9191/socket.io/;
    }

 
    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/share/nginx/html;
    }

    ssl_certificate /etc/nginx/conf.d/sslcert/xxx.pem;
    ssl_certificate_key /etc/nginx/conf.d/sslcert/xxx.key;

}

Server:

const server = require('http').Server(app)
const io = require('socket.io')(server)
io.on('connection', (socket) => {
    handleUserConnect(socket)
  
  socket.on("disconnect", () => {
   handleUserDisConnect(socket)
  });
})

server.listen(9191, function () {
  console.log('Server listening on port 9191')
})

Client(react):

    const socket = io.connect('', { secure: true, query: `userId=${this.props.user._id}` })

        socket.on('notifications', data => {
            console.log('Get messages from back end:', data)
            this.props.mergeNotifications(data)
        })

Server side:

var ssl_options = {
    ca: [fs.readFileSync('../ssl/cert1.crt'), fs.readFileSync('../ssl/cert2.crt'), fs.readFileSync('../ssl/cert3.crt')],
    key: fs.readFileSync('../ssl/xxx.key'),
    cert: fs.readFileSync('../ssl/xxx.com.crt'),
};
var wssServer = https.createServer(ssl_options,app);  // Express app
wssServer.listen(4433, '0.0.0.0');
global.io = require("socket.io")();
io.listen(wssServer);
io.on( "connection", function( socket ) {
    console.log( "user connected" );
});

Client-side (no luck with the built-in WebSocket API):

<script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/3.1.3/socket.io.js"></script>
<script>
   const socket = io("https://xxx.co:4433",{ transports: ['websocket', 'polling', 'flashsocket'] });
</script>

I needed to get this to work with Debian 10, ISPConfig 3 and Let's Encrypt. Took me a while to work out the specifics. Maybe this saves someone else some time…

Server-side:

const fs = require('fs');
const https = require('https');
const express = require('express');
const socketio = require('socket.io');
const app = express();
const https_options = {
    key: fs.readFileSync('/var/www/clients/client1/web1/ssl/your-domain.com-le.key'),
    cert: fs.readFileSync('/var/www/clients/client1/web1/ssl/your-domain.com-le.crt'),
    ca: fs.readFileSync('/root/.acme.sh/your-domain.com/fullchain.cer'),
    requestCert: false,
    rejectUnauthorized: false
}
const server = https.createServer(https_options, app);
server.listen(3000, () => {
    console.log('server started ok');
});
const io = socketio(server, {
    cors: {
        origin: "https://your-domain.com",
    },
    secure: true
});
io.on('connection', (sock) => {
    console.log('someone connected');
}

Client-side:

const sock = io('https://your-domain.com:3000/');    
sock.on('status', (text) => {
    add_text($('#status'), text);
});