Why I get CORS error in server while using socket.io

Question

I'm getting CORS error in server but I'm not getting this error in local. My project is working in local but when I try to connect my socket.io api in server I'm getting this error in console:

Access to XMLHttpRequest at 'https://my-web-site.com.tr/socket.io/?EIO=4&transport=polling&t=ORwXVX_' from origin 'null' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.

My api code is like this:

const cors = require('cors');
const express = require('express');
const app = express();
const http = require('http').Server(app);

const port = process.env.PORT || 3200;

app.use(cors({
    origin: '*'
}));

const io = require('socket.io')(http, {
    cors: {
        origin: '*',
        methods: ["GET", "POST"],
        allowedHeaders: ["*"],
        credentials: true
    }
}).of('/abcHub');

io.on('connection', (socket) => {
    console.log("Connected: " + socket.id);

    socket.on('disconnect', () => {
        console.log(`Disconnect ${socket.id}`);
        
    });
});


const server = http.listen(port, () => {
    console.log(`Server is running on port ${port}`);
});

My client code like this:

   <script src="node_modules/jquery/dist/jquery.min.js"></script>
   <script src = "node_modules/socket.io/client-dist/socket.io.min.js"></script>
   <script>
  
      $(document).ready(() => {
      const socket = io("https://my-web-site.com.tr/abcHub"); 

      });
   </script>

I wonder that why I don't get cors error in local but I get in server? If you have any question, you can ask. Thanks.

Did you run this command to install cors ? npm install cors --save — firatt_, Mar 19 '23 at 16:34
Did you refer to this answer? https://stackoverflow.com/a/43881141/20058276 — TengFeiXie, Mar 21 '23 at 07:38

score 1 · Answer 1 · answered Mar 21 '23 at 09:45

1

I solved. The problem is that iis is not hosting node.js project without redirection. I upload iisnode to server and did redirection settings. Then project worked. Thanks.

answered Mar 21 '23 at 09:45

fatih

149
1
1
12

score 0 · Answer 2 · edited Mar 24 '23 at 16:44

0

Try this:

const express = require("express")
const app = express()
const http = require("http")
const cors = require("cors")
const { Server } = require("socket.io") 
const corsOptions = require("./config/corsOptions.js")

app.use(cors())
const server = http.createServer(app)

const port = process.env.PORT || 3001

const io = new Server(server , corsOptions )

server.listen(port,() => {
    console.log("server listening on ","3001")
})

where the corsOptions is

const corsOptions = {
    cors: {
        origin: "*"
    }
}

edited Mar 24 '23 at 16:44

Tyler2P

2,324
26
22
31

answered Mar 19 '23 at 17:05

Mohammed Mehdi

26
5

It is same result. It is working in local but give cors error in iis server. – fatih Mar 20 '23 at 08:03

Why I get CORS error in server while using socket.io

2 Answers2