socket.IO can only connect one client (browser) at a time - node.js

I am having a problem of using socket IO to connect my server to the client(http website).
On the client, I have a button that when pressed, sends data to the server. However, this only works with one client.
If I have two clients, the first person to open the http website gets the socket IO connection, while the second person can open the page, but can't send any data to the server.
On the client side:
var socket = new io.connect('ServerIP:8090');
socket.on('message', function(obj){
if ('buffer' in obj){
//ignore this
} else message(obj);
});
On server side:
var io = io.listen(server)
, buffer = [];
io.on('connection', function(client)
{
client.send({ buffer: buffer });
client.broadcast.send({ announcement: client.sessionId + ' connected' });
chatGuests.push(client);
client.on('message', function(message){
var msg = { message: [client.sessionId, message] };
buffer.push(msg);
if (buffer.length > 15) buffer.shift();
client.broadcast.send(msg);
});
client.on('disconnect', function(){
client.broadcast.send({ announcement: client.sessionId + ' disconnected' });
});

Instead of using client.broadcast.send(something) and client.send(something) use io.emit('eventName', something). Also, for setting up the server with the variable io use
var socket = require('socket.io');
var http = require('http');
var express = require('express');
var app = express();
var server = http.createServer(app);
var io = socket.listen(server);
And then after your code:
server.listen(8090);
This allows you to use the node.js module express, which allows additional communication between the client and server (but doesn't require you to rewrite your socket.io code).
For your client code, instead of using:
socket.on('message', function(obj){
//Do something
});
Use:
socket.on('eventName', function(something){
//Do something
});
This works for multiple kinds of data passing, not just messages. You can multiple event listeners to each do different things

Related

How to properly setup socket connection from AS3 air to nodejs

I found lot of samples in here, but very old posts using very old node and adobe air versions. I made simple node js server which is working properly - tested with web browser. Node JS is version 6.11.
var http = require('http');
var sockets = [];
var server = http.createServer(function(req, res) {});
server.listen(8080);
var io = require('socket.io').listen(server);
io.set('transports', ['websocket','flashsocket']);
io.sockets.on('connection', function (socket) {
sockets.push(socket);
socket.on('disconnect', function() {
var i = sockets.indexOf(socket);
sockets.splice(i, 1);
});
socket.on("data",function(d){
console.log('data from flash: ',d);
});
socket.write(JSON.stringify({message:"blah blah"}));
});
My task is to connect it to AS3 Air application. Script looks something like this:
public class CustomSocket extends Socket {
public function CustomSocket(host:String = null, port:uint = 0) {
super();
configureListeners();
if (host && port) {
super.connect(host, port);
}
}
private function configureListeners():void {
addEventListener(Event.CLOSE, closeHandler);
addEventListener(Event.CONNECT, connectHandler);
addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler);
addEventListener(SecurityErrorEvent.SECURITY_ERROR, securityErrorHandler);
addEventListener(ProgressEvent.SOCKET_DATA, socketDataHandler);
}
....
}
It is connecting to socket with no error, but neither sending or receiving data are working. Only connecting event is fired and that's it. ProgressEvent.SOCKET_DATA is never fired. Also, on connect I send some data to node, never received.
Any idea?
Figured it out. Instead of using socket.io, like for web pages, I had to use TCP socket connection on nodejs side. When I create script like this:
var net = require('net');
var net_server = net.createServer(function(socket) {
socket.write('blah blah \n');
socket.on('data', function(chunk) {
});
socket.on('error', function(err) {});
});
net_server.listen(8000);
there is bi-directional communication which is working.

How to emit message from client side [node.js + socket.io]

I am trying to emit message from client side with socket.io ...
Here is my client code:
var socket = io.connect('http://localhost/');
socket.on('connect', function(data){
setStatus('connected');
socket.emit('subscribe', {channel:'update.comment'});
});
Server:
io.sockets.on('connection', function (socket) {
socket.emit('message', { text : 'Welcome!' });
socket.on('subscribe', function (data) {
socket.join(data.channel);
redisClient.subscribe(data.channel);
});
});
Also I get this error message in console:
GET
http://localhost/socket.io?EIO=3&transport=polling&t=1442169984269-1
404 (Not Found)
Full serever:
var app = require('express')();
var http = require('http').Server(app);
var redis = require('ioredis');
var io = require('socket.io')(http);
redisClient = redis.createClient();
//look for connection errors and log
redisClient.on("error", function (err) {
console.log("error event - " + redisClient.host + ":" + redisClient.port + " - " + err);
});
io.sockets.on('connection', function (socket) {
socket.emit('message', { text : 'Welcome!' });
//on subscription request joins specified room
//later messages are broadcasted on the rooms
socket.on('subscribe', function (data) {
socket.join(data.channel);
redisClient.subscribe(data.channel);
});
});
redisClient.on('ready', function(data) {
console.log('#redis ready');
});
redisClient.on("message", function(channel, message){
console.log(channel);
var resp = {'text': message, 'channel':channel};
io.sockets.in(channel).emit('message', resp);
});
http.listen(3000, function(){
console.log('Listening on Port 3000');
});
New Problem Recognized:
Your server is listening on port 3000, but you are attempting to connect on port 80. The error message http://localhost/socket.io?EIO=3&transport=polling&t=1442169984269-1 has no port number on it so that defaults to port 80.
That error message means that your server-side socket.io code is not initialized correctly and thus is not listening for the HTTP request that starts all webSocket connections so when the browser tries to connect on that URL to initiate a socket.io connection, there's nobody on the server-side listening so the web server returns a 404 error back to the browser.
If you are using Express, this is the minimal socket.io initialization to hook it into your server:
var express = require('express');
var app = express();
var server = app.listen(8081);
var io = require('socket.io').listen(server);
For a plain HTTP server, this is the minimal socket.io initialization:
var app = require('http').createServer(handler)
var io = require('socket.io')(app);
app.listen(80);
As always, if you show us the socket.io and web server initialization code you are using, we can help you better with your specific code issue.

var socket = io.connect('http://yourhostname/');?

I try socket.io again since v.1.0 released.
As the doc,
https://github.com/Automattic/socket.io
Server side:
var server = require('http').Server();
var io = require('socket.io')(server);
io.on('connection', function(socket){
socket.on('event', function(data){});
socket.on('disconnect', function(){});
});
server.listen(5000);
Client side
var socket = io.connect('http://yourhostname.com/');
In development, surely
var socket = io.connect('http://localhost:5000/');
It works, but I'm very uncomfortable with hardcoding the hostname(subdomain.domain) in the client code(/index.js).
The index.js is hosted by the http-sever and the socket.io is bundled to the http-server in this configuration.
Is there any smart way not to hardcode the hostname but to code in some relative path?
Thanks.
EDIT:
When I try:
var socket = io.connect('./');
The connection error:
GET http://.:5000/socket.io/?EIO=2&transport=polling&t=1401659441615-0 net::ERR_NAME_NOT_RESOLVED
is like this, so at least the port number (5000) is obtained properly without hardcoding in the client side.
Final answer.
I have totally forgotton that we can obtain the current url/domain in browser.
window.location.hostname
So, simply goes:
'use strict';
/*global window, require, console, __dirname, $,alert*/
var log = function(msg)
{
console.log(msg);
};
log('init');
$('document').ready(function()
{
var io = require('socket.io-client');
var socket = io.connect(window.location.hostname);
socket.on('connect', function()
{
log('socket connected');
});
});
You have to remember that Node.js is not a web server. It's a platform. When you specify a relative path, it doesn't know that you mean "relative to the current domain."
What you need to do is send the domain to the client when you send them the webpage (I don't know the specifics of your setup, but perhaps using a template variable?), and send them the localhost:5000 domain if you're in development, or your real domain if you're in production (alternatively, you can use a library like nconf, but you get the idea).
dunno, so far I did as follows:
'use strict';
/*global window, require, console, __dirname, $,alert*/
var log = function(msg)
{
console.log(msg);
};
log('init');
$.getJSON("../config.json", function(data)
{
var host = data.url;
var port = data.port;
$('document').ready(function()
{
alert(host + ':' + port);
var io = require('socket.io-client');
var socket = io.connect(host);
socket.on('connect', function()
{
log('socket connected');
});
});
});
It's browserified with socket.io-client.

How to connect two node.js servers with websockets?

Here's my problem:
I have server A, running node.js and using socket.io for communicating with clients (web browsers). This all is running fine and dandy.
However, now that I have server B, which also needs to connect to server A through websockets, I have hit a wall. None of the node.js websocket clients I've found won't work with the socket.io on the server A.
So, this is the case I'm striving for:
.--------. .----------. .----------.
| CLIENT | <--> | SERVER A | <--> | SERVER B |
'--------' '----------' '----------'
Client-server A connection is done through socket.io
Now, Server B (running node.js) should connect to server A via websocket (in order to go through port 80). But...
Even the example code in socket.io-client module doesn't work... :/
// Connect to server
var socket = new io.Socket('localhost', {port: 8080});
socket.connect();
// Add a connect listener
socket.on('connect', function(socket) {
console.log('Connected.');
});
The code just passes without any errors and execution ends after few seconds.
Update: Code samples
Server (which works just fine) looks like this:
// Load requirements
var http = require('http'),
io = require('socket.io');
// Create server & socket
var server = http.createServer(function(req, res){
// Send HTML headers and message
res.writeHead(404, {'Content-Type': 'text/html'});
res.end('<h1>Aw, snap! 404</h1>');
});
server.listen(8080);
io = io.listen(server);
// Add a connect listener
io.sockets.on('connection', function(socket) {
console.log('Client connected.');
// Disconnect listener
socket.on('disconnect', function() {
console.log('Client disconnected.');
});
});
Client looks like this
console.log('1');
// Connect to server
var io = require('socket.io-client')
var socket = new io.Socket('localhost', {port: 8080});
socket.connect();
console.log('2');
// Add a connect listener
socket.on('connect', function(socket) {
console.log('Connected!');
});
console.log('3');
1, 2 and 3 prints out just fine, no errors, and few seconds later the process just exits
Also, server A doesn't output anything to the log, even though I have the socket.io logging set on "everything".
For future people:
Here is 2 very simple Node.js apps that use socket.io to connect, send and receive messages between each other.
Required package is:
npm install socket.io
Node-App-1 server.js:
var io = require('socket.io').listen(3000);
io.on('connection', function (socket) {
console.log('connected:', socket.client.id);
socket.on('serverEvent', function (data) {
console.log('new message from client:', data);
});
setInterval(function () {
socket.emit('clientEvent', Math.random());
console.log('message sent to the clients');
}, 3000);
});
Node-App-2 client.js:
var io = require('socket.io-client');
var socket = io.connect("http://localhost:3000/", {
reconnection: true
});
socket.on('connect', function () {
console.log('connected to localhost:3000');
socket.on('clientEvent', function (data) {
console.log('message from the server:', data);
socket.emit('serverEvent', "thanks server! for sending '" + data + "'");
});
});
Turns out I was using old examples, for some reason, even though I triple checked them. Well, doh.
Also, it turned out that the socket.io-client is broken on latest Node (6.x.x). Managed to find an update from github for it, replaced the files and yay, everything's working!
Edit: Unfortunately I didn't save any links to working examples but after quickly skimming through the code it seems that the only changes were to the client code, which now looks like this:
console.log('1');
// Connect to server
var io = require('socket.io-client')
var socket = io.connect('localhost:8080', {reconnect: true});
console.log('2');
// Add a connect listener
socket.on('connect', function(socket) {
console.log('Connected!');
});
console.log('3');
Here is a snippet of code I wrote, it's using socket.io 1.0.6 and socket.io-client 1.0.6. The case is the following:
Server A (Socket.io Client) <---> Server B (Socket.io Server)
Server B (Server):
// Load requirements
var http = require('http'),
io = require('socket.io');
// Create server & socket
var server = http.createServer(function(req, res)
{
// Send HTML headers and message
res.writeHead(404, {'Content-Type': 'text/html'});
res.end('<h1>Aw, snap! 404</h1>');
});
server.listen(8080);
io = io.listen(server);
// Add a connect listener
io.sockets.on('connection', function(socket)
{
console.log('Client connected.');
// Disconnect listener
socket.on('disconnect', function() {
console.log('Client disconnected.');
});
});
Server A (Client):
console.log('1');
// Connect to server
var io = require('socket.io-client');
var socket = io.connect('http://localhost:8080', {reconnect: true});
console.log('2');
// Add a connect listener
socket.on('connect', function(socket) {
console.log('Connected!');
});
console.log('3');
If I'm using localhost:8080 only on the client server it doesn't connect.

Socket.io Error (socket.send is not a function)

I'm trying out Websockets/Node.js/Socket.io/Express for the first time and I'm trying to create a simple chat program. Everything runs fine and I see both clients in my node termial.
But when I try to execute my socket.send(), I get an error in Firefox (socket.send is not a function). It doesn't complain about socket.connect() so I know the socket.io.js is loaded.
Here is my server code:
var sys = require('util');
var express = require('express');
var io = require('socket.io');
var app = express.createServer();
app.listen(8080);
app.use(express.static(__dirname));
app.get('/', function (req, res) {
res.render('index.html', {
title: 'Chat'
});
});
var socket = io.listen(app);
socket.on('connection', function (client) {
client.on('message', function (message) {
console.log("Message: " + JSON.stringify(data));
socket.broadcast(message);
});
client.on('disconnect', function () {});
});
My client code:
<script src="http://localhost:8080/socket.io/socket.io.js"></script>
var socket = new io.Socket("http://localhost:8080");
socket.connect();
Then I do some code to get the chat message and send it.
socket.send(JSON.stringify(values));
Explanations
You haven't initialized Socket.io correctly on the server-side and client-side.
Client Side
new io.Socket("http://localhost:8080"); doesn't give you the object that you want, you need new io.connect("http://localhost:8080");.
You need to wait until the client is connected to the server before sending a message.
Server side
socket is the object send back by Socket.IO, you need to use socket.sockets to have access to on.
To broadcast a message, you need to use the client object like this: client.broadcast.send()
The variable data doesn't exist on your broadcast. You probably mean message.
Solution
Server
var sys = require('util'),
express = require('express'),
io = require('socket.io'),
app = express.createServer();
app.listen(8080);
app.use(express.static(__dirname));
app.get('/', function (req, res) {
res.render('index.html', {
title: 'Chat'
});
});
var io = io.listen(app);
io.sockets.on('connection', function (client) {
client.on('message', function (message) {
console.log("Message: " + JSON.stringify(message));
client.broadcast.send(message);
});
client.on('disconnect', function () {});
});
Client
<script src="http://localhost:8080/socket.io/socket.io.js"></script>
<script>
var socket = new io.connect("http://localhost:8080"),
connected = false;
socket.on('connect', function () {
connected = true;
});
// Use this in your chat function.
if (connected) {
socket.send(JSON.stringify(values));
}
</script>
socket.broadcast(message); should be io.sockets.emit('key', message);
when you use the socket object passed in threw the connect event your only emitting information to that client, to emit to all clients you have to use io.sockets.emit().
also with socket.send(JSON.stringify(values)); I think you want to do socket.emit(namespace, data);
see my connection file from one of my projects here: https://github.com/AdminSpot/HangoutCanopy/blob/master/javascripts/connection.js
You have to wait for socket.io to connect on the client side
var socket = new io.Socket("http://localhost:8080");
socket.connect();
socket.on('connect', function() {
socket.emit('event', data);
});

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