Node js - Socket.io-client is not connecting to socket.io server - node.js

I am trying to connect to a socket.io-client using the following code:
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.');
});
});
Client:
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');
I don't get the Connected console log or Client Connected console log and I don't know why! The code sample is taken from another question posted: Link and I don't see any solution to the problem...

Use the same version of socket io client and server. It will work perfectly.

Also you need to add protocol with path.
change
var socket = io.connect('localhost:8080', {reconnect: true});
to
var socket = io.connect('http://localhost:8080', {reconnect: true});

Assuming you are using a socket.io version greater than 1.0, on the server, change this:
// Add a connect listener
io.sockets.on('connection', function(socket) {
console.log('Client connected.');
// Disconnect listener
socket.on('disconnect', function() {
console.log('Client disconnected.');
});
});
to this:
// Add a connect listener
io.on('connection', function(socket) {
console.log('Client connected.');
// Disconnect listener
socket.on('disconnect', function() {
console.log('Client disconnected.');
});
});
See the socket.io documentation reference here.
You don't want to be listening for this event only on already connected sockets. You want to listen for this event on any socket, even a newly created one.
Also, be very careful when reading socket.io code in random places on the internet. Some things changed significantly from v0.9 to v1.0 (I don't know if this was one of those things or not). You should generally always start with the socket.io documentation site first since that will always represent the latest version. Then, if looking at other internet references, make sure you only use articles that are later than mid-2014. If you don't know the vintage of an article, it's best not to rely on it without corroboration from a more recent article.

you can use localhost. It works for me as well. You must use your ip address and port that works for you

Related

Why is my connection of a NodeJS server (Sails) to another NodeJS Server (Express4) using Socket.IO failing?

I am trying to connect my Node.JS (written using Sails.JS) app to another Node.JS server (Express4 / Socket.io) using socket.io-client.
My Sails Service app/services/Watcher.js looks like
var client = require('../../node_modules/sails/node_modules/socket.io/node_modules/socket.io-client');
// callback of the form function(socket)
exports.connect = function(callback) {
sails.log.debug("will connect socket to", sails.config.watcher.uri, "with Socket.io-client version", client.version);
var socket = client.connect(sails.config.watcher.uri);
socket.on('connect', function(){
sails.log.debug("connected");
socket.on('disconnect', function(){
sails.log.debug("Disconnected");
});
socket.on('error', function(err){
sails.log.debug("Could not connect", err);
});
callback(socket);
});
};
This is invoked from config/bootstrap.js as follows:
Watcher.connect(function(socket){
sails.log.debug("Connected watcher to relay with socket", socket);
});
On the Express side my server relay.js is as simple as:
var app = require('express')(),
http = require('http').Server(app),
io = require('socket.io').listen(http),
port = process.env.RELAY_PORT || 8000;
app.get('/', function(req, res) {
var response = {message: "some response"}; // to be implemented.
res.json(response);
});
http.listen(port, function () {
console.log("Relay listening on port " + port);
});
io.sockets.on('connection', function (socket) {
console.log("Connection opened", socket);
socket.on('disconnect', function () {
console.log("Socket disconnected");
});
});
When I run node relay it dutifully reports
Relay listening on port 8000
When I sails lift my other server it dutifully reports
will connect socket to http://localhost:8000 with Socket.io-client version 0.9.16
But I never see an actual connection.
If I point a browser at localhost:8000 I get the {"message":"some response"} JSON response I expect.
Why isn't my relay server accepting a connection from my socker.io-client app?
The issue here is probably that you're trying to re-use the
socket.io-client from inside of Sails. In general, if you're require()-ing dependencies of Sails directly in your project, you're heading in the wrong direction. In this case, socket.io-client caches configurations and connections, so your require isn't getting a fresh copy.
Instead, do
npm install socket.io-client#~0.9.16 --save
in your project and require with
var client = require('socket.io-client');
that'll give you a fresh copy of the socket client to work with, and avoid any conflicts with the Sails core's version.

client-client communication using nodejs

I would like to communicate 2 web pages page1.html and page2.html. I have thought that page1 is related to a app1.js node application and page2.html to a app2.js node application. The idea is to send data from the page1.html to app1.js using websockets and then the app1.js will send the data to the page2.html. My first idea is that app1.js sends data to app2.js and then app2.js to the page2.html. I know how to use web sockets to communicate (client-server) the page1.html with the app1.js but how to send data from app1.js to app2.js? In the app1.js I have
io = require('socket.io').listen(3000); //and
io.sockets.on('connection', function (socket) {
socket.on('GETDATAFROMPAGE1', function (data){
.....I Get data to be sent to app2?
});
}
Do I need to create a new io2 for other port? How can I do to send data to the app2.html?
I know how to do a client server communication but I don't know server-server communication and how to mix both
Summary: page1.html -> app1.js --> app2.js --> page2.html using websockets
Thanks for your answer
Seems like you can implement this in an easy way but you don't know because you said you want to send data from page1 to app1 and from app1 to app2 and from app2 to page2. So Basically if I got you correct, you want to send data from page1 to page2. You can create only one server in app.js and use socket.io to connect both pages to send data to each other.
Let's say you have page1.html:
socket.emit('GETDATAFROMPAGE1', data);
and page2.html:
socket.on('dataFromPage1', function(data){
//do something
});
and you have app.js:
io.sockets.on('connection', function (socket) {
socket.on('GETDATAFROMPAGE1', function (data){
socket.broadcast.emit('dataFromPage1', data)
});
}
The broadcast event only emits to other than the sender of the data. Now you can send data from page1.html to server and from server to page2.html
You have two options:
1) create HTTP routes which handle posting/getting data back end forth between both servers (I assume that it is trivial and you know how to configure route and get/post date between the servers)
2) you can use sockets on the server level as well. Take a look at node's net documentation http://nodejs.org/api/net.html
your code would look something like this:
//server
var net = require('net');
var server = net.createServer(function(c) { //'connection' listener
console.log('server connected');
c.on('end', function() {
console.log('server disconnected');
});
c.write('hello\r\n');
c.pipe(c);
});
server.listen(8124, function() { //'listening' listener
console.log('server bound');
});
//client
var net = require('net');
var client = net.connect({port: 8124},
function() { //'connect' listener
console.log('client connected');
client.write('world!\r\n');
});
client.on('data', function(data) {
console.log(data.toString());
client.end();
});
client.on('end', function() {
console.log('client disconnected');
});
You can also use json-socket.

Socket.io - Close Server

I have a socket.io server in my app, listening on port 5759.
At some point in my code I need to shutdown the server SO IT IS NOT LISTENING ANYMORE.
How Can I accomplish this?
Socket.io is not listening on an http server.
You have a server :
var io = require('socket.io').listen(8000);
io.sockets.on('connection', function(socket) {
socket.emit('socket_is_connected','You are connected!');
});
To stop recieving incoming connections
io.server.close();
NOTE: This will not close existing connections, which will wait for timeout before they are closed. To close them immediately , first make a list of connected sockets
var socketlist = [];
io.sockets.on('connection', function(socket) {
socketlist.push(socket);
socket.emit('socket_is_connected','You are connected!');
socket.on('close', function () {
console.log('socket closed');
socketlist.splice(socketlist.indexOf(socket), 1);
});
});
Then close all existing connections
socketlist.forEach(function(socket) {
socket.destroy();
});
Logic picked up from here : How do I shutdown a Node.js http(s) server immediately?
This api has changed again in socket.io v1.1.x
it is now:
io.close()
The API has changed. To stop receiving incoming connections you should run:
io.httpServer.close();

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.

How does one properly shutdown socket.io / websocket-client?

I'm trying to create a test using LearnBoost's socket.io and the node-websocket-client. Communication between the client and server work great. After all communication is done, I close both the client and the server. Yet the program hangs, waiting on some unknown callback. Two questions:
What is the following program waiting for?
Is there a tool for diagnosing outstanding callbacks in node programs?
var connect = require('connect'),
io = require('socket.io'),
WebSocket = require('websocket-client').WebSocket;
var port = 7111;
var server = connect.createServer();
var socket = io.listen(server);
socket.on('connection', function(client) {
client.send('Welcome!');
client.on('message', function(message) {
console.log(message);
});
client.on('disconnect', function() {
console.log('closing');
server.close();
});
});
server.listen(port, function() {
var ws = new WebSocket('ws://localhost:' + port + '/socket.io/websocket');
ws.onmessage = function(message) {
console.log(message.data);
};
setTimeout(function() {
ws.send('~m~3~m~Yo!');
ws.close();
}, 10);
});
EDIT: changed the variable name of the WebSocket to ws to avoid confusion
var socket = io.listen(server);
You've created a socket on a port. You've never closed it.
socket.server.close() closes your (socket.io) socket.
When in doubt read the socket.io github examples
socket.server === server It's the server you pass in, in the liste statement so it's closed. I'm not sure what it's waiting for.
Below a way to shutdown all the connections and be able to run multiple expresso tests (using socket.io and socket.io-client).
The solution is tricky and buggy but works on 0.8.5. The main problem is regarding the library to use websockets (node-websocket-client).
Currently, on socket.io, the OS contributors have patched the websocket client. So, we must do the same on our socket.io-client npm package to be able to use finishClose method on the socket client side. Socket.io-client uses the websocket library as npm package, so you must find the file (websocket.js) and substitute it with the same on socket.io.
Afterwards, you could use finishClose method to ensure the connections are closed and with some custom server/client socket settings, the tests will run correctly.
var io = require("socket.io").listen(port);
io.set('close timeout', .2);
io.set('client store expiration', .2);
var client = require("socket.io-client").connect( "http://localhost", { port: port , 'reconnect': false, 'force new connection': true});
client.on('connect', function() {
client.disconnect();
});
client.on('disconnect', function() {
client.socket.transport.websocket.finishClose();
io.server.close();
});
io.server.on('close', function() {
setTimeout( function() {
done();
}, 500);
});
Hope, somebody can help.
The program is waiting because socket.io (server) is still listening for incoming connections. I don't know of any way to stop listening.

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