Socket.io error hooking into express.js

Question

Socket.io error hooking into express.js

I'm trying to hook socket.io and express.js together:

var socket = require('./socket_chat/socket.js');

var express = require('express'),
    app = module.exports.app = express();

    var io = require('socket.io').listen(app);

    app.use(express.static(__dirname + '/app'));

io.sockets.on('connection', socket);

At the line: var io = require('socket.io').listen(app); I'm getting an error:

Error: You are trying to attach socket.io to an expressrequest handler function. Please pass a http.Server instance.

There doesn't seem to be anything on SO/google about this error...

javascript
node.js
express
socket.io

Answer 1

You should use http module:

var http = require('http');
var express = require('express'),
    app = module.exports.app = express();

var server = http.createServer(app);
var io = require('socket.io').listen(server);  //pass a http.Server instance
server.listen(80);  //listen on port 80

//now you can use app and io

More details you can find in a documentation: http://socket.io/docs/#using-with-express-3/4