无法从Win Forms C＃应用程序连接到远程Node.js Socket.IO服务器

Question

I have created C# application that connects to Socket.IO server and send/receive some data. I'm using SocketIoClientDotNet which works when Socket.IO server is on my localhost (windows) . But for production, Socket.IO server is on remote Debian Linux server and my app won't connect to it. However I know that remote Socket.IO server is working since I'm also using Express module to run web server which also connects to same Socket.IO only different namespace, and it connects just fine.

I'm using this code to connect to Socket.IO server

Socket socket = IO.Socket("http://someurl:9910/client");

On both servers (local and remote) Socket.IO version is 2.0.4.

EDIT

In node.js code is like this, so i know when somebody is connected:

var express = require('express');
var app = express();
var server = require('http').createServer(app);
var io = require('socket.io').listen(server, {log: false, serveClient: true});

app.use('/', express.static(__dirname + '/html'));
server.listen(9910);

var ioClient = io.of('/client');
var ioManager = io.of('/manager');

ioClient.on('connection', function (socket) {
    debug("Client connected", "Client connected with ID \x1b[36m"+socket.client.id+"\x1b[0m");
}

ioManager.on('connection', function (socket) {
    debug("Manager connected", "Manager connected with ID \x1b[36m"+socket.client.id+"\x1b[0m");
}

There is also debug function which is not relevant.

in C# Win Forms app it looks something like this

using Newtonsoft.Json;
using Quobject.SocketIoClientDotNet.Client;

Socket socket;

private void frmMain_Load(object sender, EventArgs e)
        {
            socketConnect();
        }

private void socketConnect()
        {
            socket = IO.Socket("http://someurl:9910/client");
        }

        private void socketDisconnect()
        {
            socket.Disconnect();
        }

        private void initListeners()
        {
            socket.On(Socket.EVENT_CONNECT, () =>
            {
                Console.WriteLine("SOCKET CONNECTED");
            });
        }

So on my local server I can see debug messages:

06.03.2018. 11:40:12: Client connected; Client connected with ID SknUAgkyMg61QtfUAAAA

But on remote server nothing is happening. Also there is none C# exceptions except few of my debug messages.

Answer 1

After long time debugging I found that it is a problem in socket.io packet installed using npm.

It appears that some socket.io dependency (not sure which one) is updated and broken since I have installed socket.io packet on my PC a month ago.

Solution was to copy whole socket.io folder from node_modules folder from my PC to the server.

After that everything worked as it should. However many people wont have this issue since it is revealed only on C# to Node.JS socekt.io relation but it is good to know.