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Socket.io Basic web socket connection with url?

My client is making a WebSocket request to this URL: ws://localhost:3000/feed/XBTMUR
In my server, I have NodeJs running express. I want to use Socket.io to listen to clients connecting to this URL and send feed data regularly.
I tried this but it is not working:
var app = require('../app');
var http = require('http');
/**
* Get port from environment and store in Express.
*/
var port = normalizePort(process.env.PORT || '3000');
app.set('port', port);
/**
* Create HTTP server.
*/
var server = http.createServer(app);
/**
* Listen on provided port, on all network interfaces.
*/
var io = require('socket.io')(server);
var feed =
io.of('/feed/XBTMUR').on('connection', function (socket) {
socket.emit('news', { hello: 'world' });
socket.on('my other event', function (data) {
console.log(data);
});
});
io.on('connection', function(socket) {
console.log('a user connected, id ' + socket.id);
socket.on('disconnect', function() {
console.log('a user disconnected, id ' + socket.id);
})
})
setInterval(()=>{
io.sockets.emit('this', { receivers: 'everyone'});
},1000)
server.listen(port);
The client is not using Socket io.

I feel the the implementation is wrong while reading the documentation.
var feed = io.of('/feed') // `/feed` is the namespace
.on('connection', function (socket) {
socket.to('XBTMUR', { hello: 'world' }); // `XBTMUR` is the room / socket id
});
Hope this helps.

Triggering socket.io real-time notifications from Express 4 middleware

I am building a real-time notification system using socket.io. This is my server-side code at the moment:
bin/www:
var app = require('../app');
var server = http.createServer(app);
var io = app.io
io.attach(server);
server.listen(port, function(err) {
if (err) console.log(err);
console.log('Listening on port ' + port + '...');
});
app.js:
var socket_io = require('socket.io');
var express = require('express');
var app = express();
var io = socket_io();
app.io = io;
require('./config/socket')(app.io);
config/socket.js:
var User = require('../controllers/user');
module.exports = function (io) {
io.on('connection', function (socket) {
console.log('Socket.io connected');
socket.emit('connection', "Connection created.");
socket.on('send notification', function(data) {
User.createNotification(socket.request.user, data);
});
});
};
routes/index.js:
var express = require('express');
var User = require('../controllers/user');
var router = express.Router();
router.post('/order', User.order);
module.exports = router;
controllers/user.js:
var User = require('../models/user').model;
var io = require('socket.io');
module.exports = {
order: function(req, res) {
/* some create order code */
io.emit('send notification', 'Your order was successful!');
res.sendStatus(200);
}
}
I keep getting the error TypeError: io.emit is not a function whenever I try to call the route POST /send even though I am clearly initiating socket.io in my app.js and bin/www files and requiring it in controllers/user.js. All the examples I've seen online emit notifications from within this part:
io.on('connection', function (socket) {
socket.emit(event, msg);
});
but I want my notifications to be triggered from the middleware so I can send custom notifications to the user when certain events happen in the application backend.

Try the following instead:
io.on('connection', function(socket){
socket.on('xxx', function(obj){
io.emit('xxx', {xxx: xxx})
})
})
This should suppress your TypeError:.

How to emit message using socket.io from two different files?

I am working with socket.io , so i created server on app.js and connect socket to client and i see emit('message') is printing to the client console, Now i want to send another message from different file consumer.js and emit message to client but its throwing exception on server side io.on is not a function. Any idea what is implemented wrong in consumer.js file ?
app.js
var express = require('express');
var app = express();
var consumer = require('./consumer');
var server = require('http').createServer(app);
var io = require('socket.io')(server);
app.use(express.static(__dirname + "/public"));
io.on('connection', function(client) {
console.log('Client connected...');
client.emit('message', ' hello from server');
});
server.listen(3000, function () {
console.log('Example app listening on port 3000!');
consumer.start();
});
consumer.js
var io = require('socket.io');
function startConsumer(consumer) {
consumer.on('message', function (message) {
logger.log('info', message.value);
io.on('connection', function(client) {
console.log('Consumer connected...');
client.emit('Consumer-Message', 'Message from dit consumer');
});
});
consumer.on('error', function (err) {
console.log('error', err);
});
};
exports.start = start;
angularCtrl.js
socket.on('message',function (data) {
console.log(data);
});
socket.on('Consumer-Message',function (data) {
console.log(data);
});

Why can't I see in console.log() the server code of socket.io?

I am starting to learn how to use socket.io and I've been trying to figure this out for the last couple of days but I don't get 2 things.
Why, after starting the server and loading my respective url (localhost:8088) does it take so long for my alert to show up?
Why can't I see the server code of socket.io? for example in the next chunk of code I never see in console my data from "my other event".
server (app.js):
var app = require('express')()
, server = require('http').createServer(app)
, io = require('socket.io').listen(server);
server.listen(8088);
app.get('/', function (req, res) {
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 (index.html):
<script src="/socket.io/socket.io.js"></script>
<script>
var socket = io.connect();
socket.on('news', function (data) {
console.log(data);
alert(data.hello);
socket.emit('my other event', {
my: 'data'
});
});
</script>

It might be the incompability between express 3.0 and socket.io
Try this:
var express = require('express'),;
var http = require('http');
var app = express();
var server = module.exports = http.createServer(app);
var io = require("socket.io").listen(server);
server.listen(8088);

socket.io + express networkerror: 404 [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
socket.io: Failed to load resource
A simple express + socket.io hellow world app seems doesnt work, i keep getting
"NetworkError: 404 Not Found -
http:// localhost:3002/socket.io/socket.io.js"
Anyone know this issue?
code:
app.js
var express = require('express'),
http = require('http');
var app = express();
var server = http.createServer(app);
var io = require('socket.io').listen(server);
app.configure(function () {
app.use(express.static(__dirname + '/public'));
});
app.listen(3002);
io.sockets.on('connection', function(socket) {
socket.emit('news', {hello: 'world'});
socket.on('my other event', function (data) {
console.log(data);
});
});
index.html
<script src="/socket.io/socket.io.js"></script>
<script>
var socket = io.connect('http://localhost');
socket.on('news', function (data) {
console.log(data);
socket.emit('my other event', { my:'data' });
});

Your Socket.IO server is listening on port 3002, but you connected to:
var socket = io.connect('http://localhost');
which by default uses standard port 80. Try this:
var socket = io.connect('http://localhost:3002');
Also you will probably have to change localhost to the IP of your machine.
Side note: If you are running Express Server and Socket.IO server on the same port, then you can simply do:
var socket = io.connect();