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!
Related
I am on the process of building a chat application with nodejs, reactjs mongo and socket.io.My chat app consists of both one to one and group chats.I have built a schema for group chat and i am inserting group names along with its members and their chats in the table.Since im a beginner towards socket.io, I dont know where to put the socket logic that needs to be fired after the db post operation.Can some one suggest any examples for me?
Update your code accordingly:
=> server.js file
// Declare socket.io
const io = require('socket.io')(server);
// Add middleware to set socket.io in
app.use((req, res, next)=>{ res.locals['socketio'] = io; next(); });
=> In your controller file
// Get the value of socket.io
module.exports = your_function_name = (req, res) => {
const io = res.locals['socketio']
// Use io when you need.
});
Hope this solves your query.
You can separate you socket related code by following way :
==>app.js
var express = require('express');
var socket = require('./socketServer');
var app = express();
var server = app.listen((config.node_port || 3000), function () {
console.log('Listening on port ' + (config.node_port || 3000) + '...');
});
socket.socketStartUp(server);
module.exports = app;
==>socketServer.js
var io = require('socket.io')();
var socketFunction = {}
socketFunction.socketStartUp = function (server) {
io.attach(server);
io.on('connection', function (socket) {
console.log("New user is connected with socket:", socket.id);
})
}
module.exports = socketFunction;
You can also check node API startup code with socket functionality in below link:
Node API Start up
Hope this answer is helpful to you
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
Either I have a fundamental misunderstanding of how socket.io works (highly likely), or I am just finding some bug that nobody knows about (nearly impossible).
I've been trying to integrate express with socket.io. On the client side, everything works fine: user clicks button, event emits, everybody's happy.
However, let's say I want to emit this event from within an express route before rendering a page. The event never seems to be emitted. From all the questions on this that I've looked at, I'm supposed to be able to simply plug my "io" instance into my app and then access it from within my routes.
So this is my setup...
// index.js
var app = express();
var port = process.env.PORT || 3700
var io = require('socket.io').listen(app.listen(port));
io.on('connection', function (socket) {
console.log("Socket connected on port " + port)
socket.on('send', function (data) {
console.log("WAFFLES")
});
});
console.log('The magic happens on port ' + port);
require('./app/routes.js')(app, io);
// app/routes.js
module.exports = function(app, io){
app.get('/', function(req, res){
io.on('connection', function (socket) {
console.log("Hello from the route!")
socket.emit('send', {message: 'urdum'})
});
res.render('index')
})
}
So in this instance, I want to be able to go into the / route, see "Hello from the route" and then "WAFFLES" logged to the console after emitting the "send" event. Instead I get absolutely nothing.
I've tried to pass in "io" via app.set('socketio', io). But no matter what, nothing works.
I've also tried emitting the event within the route without the io.on('connection') and simply just doing
io.emit('send' ...)
OR
io.sockets.emit('send' ...)
I have a fundamental misunderstanding of how socket.io works (highly likely)
You are right,
This is typical setup for socket-io, read more in https://socket.io/docs/
// index.js
var express = require('express');
var socketio = require('socket.io');
var http = http = require('http');
var app = express();
// Attach Socket.io
var server = http.createServer(app);
var io = socketio.listen(server);
app.set('socketio', io); // <-- bind socket to app
app.set('server', server); // <-- optional
io.on('connection', function (socket) {
console.log("Socket connected on port " + port);
});
app.listen(3000);
server.listen(3001) // <-- socket port
// app.get('server').listen(3001); // <-- use server or app.get('server')
In your router, access socket by req.app.get('socketio');
// app/routes.js
module.exports = function(app, io){
app.get('/', function(req, res){
var socketio = req.app.get('socketio');
socketio.emit('send', {message: 'urdum'});
res.render('index')
})
}
In my application i need to connect two socket.io node applications.Using socket.io-client we can do like this.But i don't know how socket.io-client works and where to include that.
First Node Application
var express = require('express')
, http = require('http');
var app = express();
app.use(function (req, res) {
app.use(express.static(__dirname + '/public'));
});
var server = http.createServer(app);
var io = require('socket.io').listen(server);
server.listen(3000);
io.sockets.on('connection',function(socket){
socket.on('eventFiredInClient',function(data){
socket.emit('secondNodeAppln',data);// i need to get this event in my 2nd node application how can i do this by using socket.io-client
});
});
Second Node Application
var express=require('express');
var http=require('http');
var app=express();
app.configure(function(){
app.use(express.static(__dirname + '/public'));
});
var server = http.createServer(app);
var serverAddress = '127.0.0.1';
var serverPort = 3000; //first node appln port
var clientio = require('socket.io-client');
var socket = clientio.connect(serverAddress , { port: serverPort });
socket.on('connect', function(){
console.log('connected');
});
socket.on('disconnect', function(){
console.log('disconnected');
});
var io = require('socket.io').listen(server);
server.listen(6509);
//here i need to get the 'secondNodeAppln' event raised in first node application.How can i do this.
You need to create a socket.io client in your first app:
var io = require('socket.io').listen(server); // this is the socket.io server
var clientio = require('socket.io-client'); // this is the socket.io client
var client = clientio.connect(...); // connect to second app
io.sockets.on('connection',function(socket) {
socket.on('eventFiredInClient',function(data) {
client.emit('secondNodeAppln', data); // send it to your second app
});
});
And in your second app, just listen for those events:
io.sockets.on('connection', function (socket) {
socket.on('secondNodeAppln', function(data) {
...
});
});
There's a bit of a race condition because the code above doesn't wait for a connect event on the client socket before passing events to it.
EDIT see this gist for a standalone demo. Save the three files to a directory, start the servers:
node serverserver &
node clientserver
And open http://localhost:3012 in your browser.
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);
});