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);
});
Related
I am using Adonis 4.1.0 and Adonis-websocket is only been available for v3. Can anyone tell me workaround for using socket.io with Adonis 4.1.0?
apparently they have been working on this not long ago, it was based on socket.io but because of some issues like memory leaks and others, they decided to use websockets directly instead, check these discussions :
https://github.com/adonisjs/discussion/issues/51
https://forum.adonisjs.com/t/integrating-socket-io-with-adonis-4/519
have you tried using socket.io without relying on Adonis ? ,
something like :
var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);
app.get('/', function(req, res){
res.sendFile(__dirname + '/index.html');
});
io.on('connection', function(socket){
console.log('a user connected');
});
http.listen(3000, function(){
console.log('listening on *:3000');
});
But you should be able to do this with Adonis by now according to : https://github.com/adonisjs/adonis-websocket-protocol
Example :
const filereader = require('simple-filereader')
const msgpack = require('msgpack-lite')
const packets = require('#adonisjs/websocket-packets')
const client = new WebSocket('ws://localhost:3000/adonis-ws')
client.onopen = function () {
// TCP connection created
}
client.onerror = function () {
// TCP connection error
}
client.onmessage = function (message) {
filereader(message, function (error, payload) {
const packet = msgpack.decode(payload)
handlePacket(packet)
})
}
function handlePacket (packet) {
if (packets.isOpenPacket(packet)) {
console.log('Server ack connection. Make channel subscriptions now')
}
if (packets.isJoinAck(packet)) {
console.log('subscription created for %s', packet.d.topic)
}
}
check this for broadcast examples using WS : https://github.com/websockets/ws#broadcast-example
Create start/socket.js file and paste following code inside it.
const Server = use('Server')
const io = use('socket.io')(Server.getInstance())
io.on('connection', function (socket) {
console.log(socket.id)
})
From Virk Himself in this forum:https://forum.adonisjs.com/t/integrating-socket-io-with-adonis-4/519
create a standalone socket io configuration file in start/socket.js
const io = require('socket.io')();
io.listen(3000);
io.on('connection', function (socket) {
console.log(socket.id)
})
to start your socket io server you can configure your server.js as below
new Ignitor(require('#adonisjs/fold'))
.appRoot(__dirname)
.preLoad('start/socket') //path of socket.js
.fireHttpServer()
.catch(console.error)
now when you start your server then it will start along with socket io
Tried different methods, but the data is sent to a maximum of one or two clients. How to send data to all the clients connected to the server ? What am I doing wrong?
Server.js:
var PORT = 3000;
var options = {
// 'log level': 0
};
var express = require('express');
var app = express();
var http = require('http');
var server = http.createServer(app);
var io = require('socket.io').listen(server, options);
server.listen(PORT);
app.get('/', function (req, res) {
res.sendfile(__dirname + '/attantions/templates/.default/template.php');
});
io.sockets.on('connection', function (client) {
client.on('attantion', function (data) {
try {
// Tried so
io.sockets.volatile.emit('attantion', data);
// And tried so
io.sockets.emit('attantion', data);
client.emit('attantion', data);
client.broadcast.emit('attantion', data );
} catch (e) {
console.log(e);
client.disconnect();
}
});
});
Client.js:
socket.emit("attantion", data);
socket.on('attantion', function (data) {
pushData(data);
});
See this post for different options for socket.io messages
Send response to all clients except sender (Socket.io)
io.sockets.on('connection', function (client) {
client.on('attantion', function (data) {
//client.emit('attantion', data ); // This will send it to only the client
//client.broadcast.emit('attantion', data); // This will send it to everyone but this client
io.emit('attantion', data); // This will send it to all attached sockets.
});
});
Edit
I wonder if this post can help you?
Socket.io - Cannot load file
I was curious how sending the php file to the client through node.js works? are you using another framework?
Could you show more of what your client code looks like? loading the lib and the instantiation of the socket.
How can I trigger an emit from the server-side with socketIO ?
I have a socket.on('My_Event') on my nodejs server and I wish to trigger that event from some place else on my server with .emit('My_Event').
My goal here is to broadcast to the client-side some notification datas.
server side - app.js
var app = express(),
server = http.createServer(app),
io = require('socket.io')(server);
io.on('connection', function(socket){
socket.on('My_Event', function(data){
socket.volatile.emit('event', data);
});
});
server.listen(config.listenPort, '0.0.0.0', 511, function() {
// config.listenPort is already defined
console.log('node Server - listening on port: ' + config.listenPort);
});
export - the module from which I'd like to trigger the event
var io = require('socket.io')();
exports.addStrategy = function(app) {
var fn = {
doSomething : function(req, res, next) {
// HERE I wish to trigger my socket event
// io.emit('MY_EVENT', {}); ????
res.status(200).json(done());
};
return fn;
};
so far I can't get it to work. is it how I should do it ?
One option is to create a single global instance of Socket.IO that could eventually be shared across multiple modules/applications.
global.socket = require('socket.io').listen(app);
Happy Helping!
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
I am working on realtime data visualization application using node.js, express and socket.io.
Requirement:
Have to emit the events based on the client request.
For example: If user enter the url as http://localhost:8080/pages socket.io should emit the topic pages to client and another user request for http://localhost:8080/locations socket should emit location to that particular user.
Code
var server = app.listen("8080");
var socket = require('socket.io');
var io = socket.listen(server);
var config = {};
io.on('connection', function (socket) {
config.socket = io.sockets.socket(socket.id);
socket.on('disconnect', function () {
console.log('socket.io is disconnected');
});
});
app.get('/*', function(req, res) {
var url = req.url;
var eventName = url.substring('/'.length);
//pages and locations
config.socket.volatile.emit(eventName, result);
});
Client Code:
//No problem in client code.Its working correctly.
Sample code as follows
socket.on('pages', function (result) {
console.log(result);
});
Problem:
It is emitting pages and locations to both the clients.
Any suggestion to overcome this problem.
I couldn't understand your approach on this, but because you said you're rendering different pages, It means you can serve different code, so what about doing it like this:
Server Side:
var server = app.listen("8080");
var socket = require('socket.io');
var io = socket.listen(server);
var config = {};
app.get('/pages', function(req, res) {
res.render('pages.html');
});
app.get('/locations', function(req, res) {
res.render('locations.html');
});
io.on('connection', function (socket) {
socket.on('pagesEvent', function(data){
socket.volatile.emit('pages', {your: 'data'});
});
socket.on('locationsEvent', function(data){
socket.volatile.emit('locations', {your: 'data'});
});
});
On Client side:
pages.html:
socket.on('connect', function(){
socket.emit('pagesEvent', {});
});
socket.on('pages', function(data){
// do stuff here
});
locations.html:
socket.on('connect', function(){
socket.emit('locationsEvent', {});
});
socket.on('locations', function(data){
// do stuff here
});
You are doing it wrong, WebSockets supposed to work same in both directions. Client emit event to Server, server emit back to Client/Subscribers.
The way you are doing things, seems like a way of implementing API, but for some reason you are trying to implement it with WebSockets, instead of XHR.