Please I have this small demo of a collaborative editor in a pub/sub fashion.
Scenario:
Server :S
Clients : A, B
A sends text S.
S receives text and brodcast to B.
B sends text to S.
S receives text and brodcast to A, A receive text, but document.getElementById is not updting the display.
I suspect the problem is with javascript execution order...
I am bit confused, can someone points me what goes wrong with my client ?
Server:
var app = require('express')();
var http = require('http').createServer(app)
var io = require('socket.io').listen(http);
//Server accepting connect on this port
http.listen(3000);
//Establishing connection to client and disconnecting
io.sockets.on('connection', function(socket){
console.log('Connected to a new client');
socket.on('room', function(room) {
socket.join(room);
console.log('join room '+ room);
});
socket.on('disconnect', function(){
socket.disconnect();
console.log('Disconnected from a client');
});
var room= 'room1';
//Data exchange between client and server
//Server receives new data from a client and broadcast it to others
socket.on('client_character',function(msg){
//receive data
console.log('Data from client'+msg.buffer);
socket.in(room).broadcast.emit('server_character',msg.buffer);
//socket.broadcast.to(room).emit('server_character', msg.buffer);
//socket.to(room).emit('server_character',msg.buffer);
});
});
Client:
Run separately on Apache server
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"/>
<title>Client</title>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdn.socket.io/socket.io-1.4.5.js"></script>
<link rel="stylesheet" type="text/css" href="styles/style.css">
</head>
<body>
<textarea id="notepad"></textarea><br/>
<script>
$(function () {
var socket = io.connect('http://localhost:3000',
{'sync disconnect on unload':false});
var room = "room1";
socket.on('connect', function() {
socket.emit('room', room);
});
//receive character from server
socket.on('server_character',function(content){
console.log('From Server:'+ content);
document.getElementById('notepad').innerHTML=content;
});
//For each typed character
$('#notepad').on('keypress',function(){
var character= $('#notepad').val();
//send character to servers
socket.emit('client_character',{buffer:character});
console.log('To Server:'+ {buffer:character} );
});
});
</script>
</body>
</html>
style.css:
#notepad{
height:500px;
width:500px;
font-size: 14px;
color: brown;
}
package.json:
{
"name": "collaborative",
"version": "0.0.1",
"description": "none",
"dependencies": {
"express": "^4.10.2",
"socket.io": "^1.4.5"
}
}
Reference Demo:
[https://www.youtube.com/watch?v=I0iikz1F1Lk][1]
I did some thanges in tour code for fix one bug in input and add more logs and this is working here with FF and Chrome ( i dont have IE here )
Server:
var app = require('express')();
var http = require('http').createServer(app);
var io = require('socket.io').listen(http);
//Server accepting connect on this port
http.listen(3000);
//Establishing connection to client and disconnecting
io.sockets.on('connection', function(socket){
console.log('Connected to a new client');
socket.on('error', function(err) {
//here i change options
console.log('Error!', err);
});
socket.on('room', function(room) {
socket.join(room);
console.log('join room: '+ room);
});
socket.on('disconnect', function(){
// socket.disconnect();
console.log('Disconnected from a client');
});
var room= 'room1';
//Data exchange between client and server
//Server receives new data from a client and broadcast it to others
socket.on('client_character',function(msg){
//receive data
console.log('Data from client: '+msg.buffer);
socket.in(room).broadcast.emit('server_character',msg.buffer);
//socket.broadcast.to(room).emit('server_character', msg.buffer);
//socket.to(room).emit('server_character',msg.buffer);
});
});
Client:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"/>
<title>Client</title>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdn.socket.io/socket.io-1.4.5.js"></script>
<link rel="stylesheet" type="text/css" href="styles/style.css">
</head>
<body>
<textarea id="notepad"></textarea><br/>
<script>
$(function () {
var socket = io.connect('http://localhost:3000',
{'sync disconnect on unload':false});
var room = "room1";
socket.on('connect', function() {
socket.emit('room', room);
});
//receive character from server
socket.on('server_character',function(content){
console.log('From Server:'+ content);
document.getElementById('notepad').innerHTML=content;
});
//For each typed character
$('#notepad').on('keyup',function(){
var character= $('#notepad').val();
//send character to servers
socket.emit('client_character', {buffer:character});
console.log('To Server:', { buffer:character } );
});
});
</script>
</body>
</html>
Related
I'm new to Socket.IO and doing some experimenting to better understand.
I'm trying to figure out how I can reference a socket/session/namespace elsewhere in the code besides the io.on section.
Googling has not proven successful
close but not quite
Socket reference in Socket.IO
I'm expecting it to be something very simple [can't see the forest for the trees]
Thank you!
Here is my sample code where I'm getting a reference error:
testsocket.js
http.listen(3000,() => {
console.log('Listening on *:3000');
})
io.on('connection', (socket) => {
console.log('a user connected');
socket.emit('displayMsg', 'Server Connected');
socket.on('disconnect', () => {
console.log('user disconnected');
});
});
var timerobj = {IdCount:1};
let timerId = setInterval(() => {
console.log(`tick ${timerobj.IdCount}`);
// \/ Reference error here
socket.emit('displayMsg',`Count ${timerobj.IdCount}`); //broadcast to all
timerobj.IdCount++;
if (timerobj.IdCount > 10){
clearInterval(timerId);
console.log('timeId exit');
};
}, 2000);
testsocket.html
<!doctype html>
<html>
<head>
<title>Socket.IO Test</title>
</head>
<body>
<h1>Testing Socket.io</h1>
<span id=messageArea>Intial page load message</span>
<script src="/socket.io/socket.io.js"></script>
<script src="https://code.jquery.com/jquery-3.4.1.min.js"></script>
<script>
const $messageArea = document.getElementById('messageArea');
var socket = io();
socket.on('displayMsg', (msg) => {
$messageArea.innerHTML = msg;
console.log('Message received and set');
});
</script>
</body>
</html>
i prepared a simple chat system while practicing node.js. but theres a problem while sending messages. quite a good amount of delay taking place while sending messages and i couldnt figure out why. can anyone help me how to improve attached code ?
server.js
var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);
app.get('/', function(request, response) {
response.sendFile(__dirname + '/index.html');
});
io.on('connection', function(client) {
client.on('messageSend', function(data) {
client.broadcast.emit('messageRecieve', data);
});
});
http.listen(9090, function() {
console.log('Listening on port 9090');
io.on('connect', function(socket) {
console.log("Connection established : " + socket.client.conn.remoteAddress);
})
});
index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Socket Test</title>
<script src="/socket.io/socket.io.js"></script>
<script>
var socket = io();
function messageSend() {
var message = document.getElementById("messageInput").value;
console.log(message);
var ul = document.getElementById("messageNode");
var li = document.createElement("li");
li.appendChild(document.createTextNode(message));
li.setAttribute("style", "font-style : italic; color : red;");
ul.appendChild(li);
socket.emit('messageSend', message);
}
socket.on('messageRecieve', function(data) {
var message = data;
var ul = document.getElementById("messageNode");
var li = document.createElement("li");
li.appendChild(document.createTextNode(message));
ul.appendChild(li);
console.log(message);
});
</script>
</head>
<body>
<input id="messageInput" type="text"> <button onclick="messageSend()">Send</button><br>
<ul id="messageNode">
</ul>
</body>
</html>
the official socket.io example sends the message to everyone, including yourself
io.on('connection', function(socket){
socket.on('chat message', function(msg){
io.emit('chat message', msg);
});
});
You sent to everyone except yourself (which is the most accurate method)
io.on('connection', function(client) {
client.on('messageSend', function(data) {
client.broadcast.emit('messageRecieve', data);
});
});
The reason for your slowdown is probably becouse your browser puts your out-of-focus tabs in a sort of sleep mode, which makes it update much less frequently... If you compare your code vs socket.io's code between computer and phone via lan. I would guess the speed for your server-sent message would be the same
Right now you are basically competing versus socket.io's "optimistic updates". It pushes the message to your client directly without waiting for the server, which your own code does. As well as browser out-of-focus low priority mode
I have read a lot of tutorial, and sample code to send data from a node.js class to an html page and show this data.
such as link1, link2,link3,link4,link5
and some others.
I am getting some data from UDP listener and need to send it after some processing to an html page to show it. here is my code:
The udp receiver:
var server_port = process.env.OPENSHIFT_NODEJS_PORT || 8080
var server_ip_address = process.env.OPENSHIFT_NODEJS_IP || '127.0.0.1'
var http = require('http'),
dgram = require('dgram'),
socketio = require('socket.io'),
fs = require('fs');
var html = fs.readFileSync(__dirname + '/html/showMap.html');
var app = http.createServer(function(req, res) {
res.writeHead(200, {
'Content-type': 'text/html'
});
res.end(html);
io.sockets.emit('welcome', { message: 'Welcome!'});
}).listen( server_port, server_ip_address, function() {
console.log('Listening');
});
var io = socketio.listen(app),
socket = dgram.createSocket('udp4');
socket.on('message', function(content, rinfo) {
console.log('got message', content, 'from', rinfo.address, rinfo.port);
io.sockets.emit('udp message', 'content' /*content.toString()*/);
});
socket.bind(5001);
and my html page which is called 'showMap.html'
<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no">
<meta charset="utf-8">
<title>Get Data</title>
<script src="/socket.io/socket.io.js"></script>
</head>
<body>
<div id="results"> This text will change </div>
<div id="date">sample another temp text</div>
<script>
// client code here
var socket = io.connect('localhost', {port: 8080});
socket.on('udp message', function(message) {
console.log(message)
document.getElementById("date").innerHTML = "My new text!";
});
socket.on('welcome', function(data) {
document.getElementById("results").innerHTML = data.message;
});
</script>
</body>
</html>
but by sending packet, html page has not changed.
Here is my console log of running code:
Atis-MacBook-Pro:startWithNode muser$ npm start
StartWithNodejs#1.0.0 start /Volumes/Project/Project/NodeJS/startWithNode
node index.js
Listening got message from 127.0.0.1 64047
What is wrong in my code?
I tested this locally. In your HTML file I made two changes and it worked.
1 - Replace io.connect('localhost', {port: 8080}); with io.connect('localhost:8080');
2 - There was a strange \u200b character at the end of the document.getElementById("date").innerHTML = "My new text!"; line. I deleted that and ended up with:
<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no">
<meta charset="utf-8">
<title>Get Data</title>
<script src="/socket.io/socket.io.js"></script>
</head>
<body>
<div id="results"> This text will change </div>
<div id="date">sample another temp text</div>
<script>
// client code here
var socket = io.connect('localhost:8080');
socket.on('udp message', function(message) {
console.log(message)
document.getElementById("date").innerHTML = "My new text!";
});
socket.on('welcome', function(data) {
document.getElementById("results").innerHTML = data.message;
});
</script>
</body>
</html>
Which replaces the content of results.
in this example you will be able to get JSON data from php file and send it to all connected clients.
RunThisFileThroughNodeJs.js
var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);
var port = process.env.PORT || 3000;
var request = require("request")
var url = "http://localhost/api/index.php";
events = require('events'),
serverEmitter = new events.EventEmitter();
app.get('/', function(req, res){
res.sendFile(__dirname + '/index.html');
});
io.on('connection', function(socket){
setInterval(
function(){
request({
url: url,
json: true
}, function (error, response, body) {
if (!error && response.statusCode === 200) {
io.emit('chat message', body);
}
});
},5000);
});
http.listen(port, function(){
console.log('listening on *:' + port);
});
Don't Forget to install express , request for nodejs
Now make this file i will call it index.html so the response of my file will be here.
index.html
<!doctype html>
<html>
<head>
<title>Prices API</title>
<script src="http://localhost/js/socket.io.js"></script>
</head>
<body>
<div id="price_list"></div>
<script>
var socket = io();
socket.on('chat message', function(msg){
document.getElementById("price_list").innerHTML = JSON.stringify(msg);
console.log(msg);
});
</script>
</body>
</html>
This question has already been answered, but I can't understand it at all. You can find it at this link.
socket.on calls its callback too many times
I have the same problem as this fellow. I'm attempting to make a chat program with socket.io, but when more than one user joins, each message outputs the number of times of how many users have been connected.
For example, when one user is connected, and he submits a message. It outputs once. When two users are connected, each of their messages output twice.
When three users are connected, each of their messages output three times.
Here is my client side code:
$('document').ready(function() {
var server = io.connect('http://localhost:8888');
$('.chat').keydown(function(event){
var save = this;
if(event.which == 13){
server.emit('message', $(save).val());
$(save).val('');
return false;
}
});
server.on('incoming', function(message){
$('#textfield').append("<p>" + message + "</p>");
});
});
Here is my server side code:
var socket_io = require('socket.io').listen(8888).sockets;
socket_io.on('connection', function(socket){
socket.on('message', function(message){
socket_io.emit('incoming', message)
});
});
Thank you!
You can use socket.broadcast.emit() to send to everyone except that socket:
var io = require('socket.io')(8888);
io.on('connection', function(socket) {
socket.on('message', function(message) {
socket.broadcast.emit('incoming', message);
});
});
UPDATE: The following example works just fine for me:
server.js:
var app = require('http').createServer(handler);
var io = require('socket.io')(app);
var fs = require('fs');
app.listen(80);
function handler (req, res) {
fs.readFile(__dirname + '/index.html',
function (err, data) {
if (err) {
res.writeHead(500);
return res.end('Error loading index.html');
}
res.writeHead(200);
res.end(data);
});
}
io.on('connection', function(socket) {
socket.on('message', function(message) {
socket.broadcast.emit('incoming', message);
});
});
index.html:
<html>
<head>
<script src="//code.jquery.com/jquery-1.11.3.min.js"></script>
<script src="/socket.io/socket.io.js"></script>
<script>
$('document').ready(function() {
var server = io.connect('http://localhost');
$('.chat').keydown(function(event) {
if (event.which == 13) {
var $save = $(this);
server.emit('message', $save.val());
$save.val('');
return false;
}
});
server.on('incoming', function(message){
$('#textfield').append("<p>" + message + "</p>");
});
});
</script>
</head>
<body>
<input type="text" class="chat">
<div id="textfield"></div>
</body>
</html>
When pressing enter, the message in the input box is only displayed once to all other connected socket.io users.
Okay, I've finally figured out the problem.
I'm using Express 4.0. That means, I'm using routes to run the server, and I had the socket io code running inside the route. Each time a user connects, it has to go through the route first, and it's all binding onto the same socket_io.
Thanks to everybody who helped!
I also faced it, like multiple socket calls in network tab and i just add this "transports" key object to socket instance, both on client and backend.
socket = io("http://localhost:3002", {
transports: ['websocket']
})
React, Node, AWS EB
Hello guys i'm having a problem in redis pub/sub because my client does not show the message i've published in redis-cli. I used the codes found here in stackoverflow and i made some modification. Here is the link and code. I hope you can help me, my goal is to publish the message to the client index.html using redis publish in redis-cli. I've done this before but i can't make it work again. Thanks in advance guys.
Here is my client index.html
<html>
<head>
<title>PubSub</title>
<script src="/socket.io/socket.io.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.4/jquery.min.js"></script>
<!-- <script src="/javascripts/socket.js"></script> -->
</head>
<body>
<div id="content"></div>
<script>
var socket = io.connect('http://localhost:3000');
var content = $('#content');
socket.on('connect', function() {
});
socket.on('message', function (message){
content.prepend(message + '<br />');
}) ;
socket.on('disconnect', function() {
console.log('disconnected');
content.html("<b>Disconnected!</b>");
});
socket.connect();
});
</script>
</body>
</html>
Here is my server.js
var express = require('express');
var app = express();
var redis = require('redis');
var http = require('http');
var server = http.createServer(app);
var socket = require('socket.io').listen(server);
var publish = redis.createClient();
app.listen(3000);
console.log("Express server listening on port 3000")
app.get('/', function (req,res) {
res.sendfile(__dirname + '/public/index.html');
});
socket.on('connection', function (client) {
var subscribe = redis.createClient();
subscribe.subscribe('pubsub');
subscribe.on("message", function (channel, message) {
publish.send(message);
});
publish.on('message', function (msg) {
});
publish.on('disconnect', function() {
subscribe.quit();
});
});
Redis will not send data to connected clients for you. You must instruct Socket.IO to emit data:
subscribe.on("message", function (channel, message) {
socket.emit('message', message);
});