Setup Server-Server SSL communication using socket.io in node.js - node.js

Question

I'm trying to setup a server to server link using socket.io over ssl connection. This is my example:
/**
* Server
*/
var app = require('express')();
var config = require('./config');
var https = require('https');
var http = require('http');
var fs = require('fs');
var server = https.createServer({key: fs.readFileSync(config.ssl.key), cert: fs.readFileSync(config.ssl.cert), passphrase: config.ssl.passphrase}, app);
//var server = http.createServer(app);
var io = require('socket.io').listen(server);
server.listen(config.port);
app.get('/', function (req, res) {
res.send('Server');
//res.sendfile(__dirname + '/index.html');
});
io.sockets.on('connection', function (socket) {
socket.emit('news', { hello: 'world' });
socket.on('my other event', function (data) {
console.log(data);
});
});
/**
* Client
*/
var io = require('socket.io-client');
//var socket = io.connect('http://localhost', {port: 8088});
var socket = io.connect('https://localhost', {secure: true, port: 8088});
socket.on('connect', function(){
socket.on('event', function(data){});
socket.on('disconnect', function(){});
});
The code works fine when ran without SSL. I suspect it could be my self-signed certificate not being accepted, but I do not know how to make the client accept it.
Can I accept a self-signed SSL certificate, or is there another approach I can take?

Answer 1

I've had to do things a little differently on the client to get this to work, by manually telling socket.io to use that Agent as well (and the secure: true is implied by https:). Here it is:
// Client
var io = require('socket.io-client');
var https = require('https');
https.globalAgent.options.rejectUnauthorized = false;
var socket = io.connect('https://localhost:3210/', { agent: https.globalAgent });
socket.on('connect', function(){ console.log('connected'); });
This is using socket.io v1.0.2.
Alternatively, I've had success with the following as well, as pointed to here: Socket.io + SSL + self-signed CA certificate gives error when connecting
process.env.NODE_TLS_REJECT_UNAUTHORIZED = '0';
var io = require('socket.io-client');
var socket = io.connect('https://localhost:3210/');
socket.on('connect', function(){ console.log('connected'); });

Answer 2

After some more searching, adding this in the client makes it work:
require('https').globalAgent.options.rejectUnauthorized = false;
/**
* Client
*/
var io = require('socket.io-client');
//var socket = io.connect('http://localhost', {port: 8088});
require('https').globalAgent.options.rejectUnauthorized = false;
var socket = io.connect('https://localhost', {secure: true, port: 8088});
socket.on('connect', function(){
socket.on('event', function(data){});
socket.on('disconnect', function(){});
});

Answer 3

The previous answers didn't do it for me. require('https').globalAgent is always undefined.
Did some seaching and found the rejectUnauthorized parameter in the docs (https://nodejs.org/api/tls.html). Not sure if it's related to SocketIO, but it somehow seems to work with self-signed certificates:
var socket = io.connect('//yourhost:8000', {secure: true, rejectUnauthorized: false})
secure: true might be optional, but I like to enforce it anyhow.

Answer 4

While all the above solutions focus on rejectUnauthorized=false, I'd like to suggest an alternative.
const https = require('https');
const rootCas = require('ssl-root-cas').create();
rootCas.addFile('cert/ca.crt');
https.globalAgent.options.ca = rootCas; // optional
const io = require("socket.io-client");
var socket = io.connect("https://...", { agent: https.globalAgent });