I want to create new sockei.io-client on the server side (with node.js) every time when server gets request. But the code below works only once and then sockei.io-client does't response. Application doesn't stop, no errors.
var http = require("http");
http.createServer(function(request, response) {
var io = require('socket.io-client');
localSocket = io.connect('http://localhost:9876/');
localSocket.on('connect', function (data) {
response.writeHead(200, {"Content-type": "text/plain"});
response.write(data.name);
response.end();
localSocket.disconnect();
});
}).listen(8080);
Socket.io server (on localhost:9876) works well - it serves clients with names (which is
data.name
in the code here).
What is wrong?
UPDATE: The problem is solved by myself: To run multiple connection for socket.io-client need to add connect option {'force new connection': true}, like that:
localSocket = io.connect('http://localhost:9876/', {'force new connection': true});
Thank you!
For those who found this on google - there is a solution for this right now:
Socket.disconnect() kicks the client (server-side). No chance for the client to stay connected :)
force client disconnect from server with socket.io and nodejs
I think you just have to remove the disconnect() line.
Related
(unnecessary backstory)
I have a nodejs server with expressjs framework that's proxy streaming a webcam feed. The reason I need this is because the mjpg stream must come from this server due to complex CORS issues.
//proxy from webcam server to avoid CORS complaining
app.get('/stream1',function(req,res){
var url="http://camera.nton.lviv.ua/mjpg/video.mjpg"
request(url).pipe(res);
});
question :
The issue is simple. request(url).pipe(res) never closes, because the source is mjpeg which literally never ends. I need to find a way to force close this pipe when the client(browser; the destination) is no longer available - as in, closes the window.
The other answers did not work for me.
This line var pipe=request(url).pipe(res);
returns the pipe instead of the request object. So I needed to break the line up.
The request object is needed to abort. Calling the .end() didn't work either, but the .abort() did the trick. It took me hours to find the answer that worked for me, so I thought I would share.
app.get('/cam/frontdoor',function(req,res){
var request_options = {
auth: {
user: '',
pass: ''},
url: 'http:/xx.xx.xx.xx/mjpg/video.mjpg',
};
var req_pipe = request(request_options);
req_pipe.pipe(res);
req_pipe.on('error', function(e){
console.log(e)
});
//client quit normally
req.on('end', function(){
console.log('end');
req_pipe.abort();
});
//client quit unexpectedly
req.on('close', function(){
console.log('close');
req_pipe.abort()
})
})
Use socket.io to monitor the remote connection
// install it on your project
npm install socket.io
// require it on server side
var socket = require('socket.io');
// listen for sockets from your server
var mysocks = socket.listen(myexpressappvar);
// keep collection of sockets for use if needed
// its good practice
var connectedSockets = [];
// add event handelers on server side
mysocks.sockets.on("connection", function(socket){
// add socket to our collection
connectedSockets.push(socket);
// you will need to bind their stream id here.
exe.....
// listen for disconnected
socket.on("disconnect", function(){
// remove socket from collection
connections.splice(connections.indexOf(socket), 1);
// destory stream here
exe...
});
});
// last thing, is add socket.io to the client side.
<script src="/socket.io/socket.io.js"></script>
// then call connect from client side js file
var socket = io.connect();
I have found out a simpler way. Add a event listener for client connection closing, and force close the pipe when it happens.
app.get('/stream1',function(req,res){
var url="http://camera.nton.lviv.ua/mjpg/video.mjpg"
var pipe=request(url).pipe(res);
pipe.on('error', function(){
console.log('error handling is needed because pipe will break once pipe.end() is called')
}
//client quit normally
req.on('end', function(){
pipe.end();
}
//client quit unexpectedly
req.on('close', function(){
pipe.end();
}
});
I just started learning NodeJS and I am trying to make a simple server-client project using Socket io.
What happens right now is that when I open localhost:8001, I don't see any logs inside the listener.sockets.on block.
var http = require('http');
var app = http.createServer(function (req, res) {
res.writeHead(200, {'Content-Type': 'text/plain'});
res.end('<h1>Hello!</h1>');
}).listen(8001);
var io = require('socket.io');
var listener = io.listen(app);
console.log("Sample Socket IO");
listener.sockets.on('connection', function (socket) {
console.log('a user connected');
socket.emit('connected', 'Welcome');
socket.on('disconnect', function () {
console.log('user disconnected');
});
});
It looks like the logging will occur when a connection happens. You setup a listening socket, so try to connect to it. Try 'telnet 127.0.0.1 8001' to connect.
The browser page needs to load the socket.io client code for one thing. That is the first thing missing that I can see. Look through the example here http://socket.io/get-started/chat/ and make sure you are following exactly at first and then make changes after you get that example working. Your server code looks a bit different from their example also.
I've got a Vagrant box set up to port-forwards a socket.io application from internal port 5000 to external port 8081; when I try to connect from the client it starts long-polling the connection but I don't see any kind of response from the server and the server app never registers a connection attempt. The connection doesn't fail or return any error response code though, it just returns a 200 code with a blank response.
// Import utilities
var http = require('http'),
socketIO = require('socket.io'),
querystring = require('querystring');
// Init servers/external connections
var server = http.createServer(function baseHandler(req, res) {
// console.log(req.headers);
res.writeHead(200);
res.end(JSON.stringify({
message: 'This server only supports WebSocket connections'
}));
}),
io = socketIO(server);
server.listen(process.env.socket_port || 5000, function() {
var sockets = [];
console.log('App connected');
});
io.on('connection', function (socket) {
console.log('Socket connected');
console.log('Socket in rooms '+ socket.rooms.join(', '));
});
The same app works just fine when I'm trying to connect from the app running directly on my PC, so my code doesn't seem to be the problem here, especially given how it's basically duplicating the basic example in the docs; not really sure how to solve this from here.
This is one of those really stupid bugs which crop up when you're working on two different problems with the same codebase at the same time. Here's the client-side code line which was breaking:
var socket = io('127.0.0.1:8081/?access_token=1d845e53c4b4bd2e235a66fe9c042d75ae8e3c6ae', {path: '/auth/socket.io'});
Note the path key is set to point to a subdirectory, /auth, which is a leftover from my work to get an nginx folder proxying to an internal port which the server was working on.
I have a node.js server communicating to a client web page, sending it message. This is working great based on the many tutorials and searching stack overflow :)
Where I am having an issue is when I attempt to startup a separate socket connection to a 3rd party cmd line executable instance runs as a socket server. The 3rd party executable does not adhere to the socket.io namespace/room type of events, so I read that socket.io-events may help where instead of:
socket.on('some key', function(){/**do stuff*/}); I could:
eventRouter.on('*', function(){/*do stuff*/});
For this communication, I am assuming I need to use socket.io-client on the node.js side in order to talk to the cmd executable, but I am getting exceptions trying to do a socket2.use(router); where socket2 is my socket.io-client and router is the socket.io-events object.
All runs on localhost, node to web page is port 8001 and node.js to executable is on port 8002. Please pardon the code, for I have been trying to get this to work for a few days and is a bit ugly now.
The cmd executable to execute and its arguments I have coming from the web page which works. I am able to start the exe. The EXE expects a ACK on each message sent, thus why you see the code emitting it back.
I have a interval where I set and update an element on the web page. I have another element that I set messages (msg).
var http = require('http');
var url = require('url');
var fs = require('fs');
var server;
server = http.createServer(function(req, res){
// your normal server code
var path = url.parse(req.url).pathname;
switch (path){
case '/':
res.writeHead(200, {'Content-Type': 'text/html'});
res.write('<h1>Hello! Try the Test page </h1>');
res.end();
break;
case '/socket.html':
fs.readFile(__dirname + path, function(err, data){
if (err){
return send404(res);
}
res.writeHead(200, {'Content-Type': path == 'json.js' ? 'text/javascript' : 'text/html'});
res.write(data, 'utf8');
res.end();
});
break;
default: send404(res);
}
}),
send404 = function(res){
res.writeHead(404);
res.write('404');
res.end();
};
server.listen(8001);
var str = "ack0";
var bytes = [];
for (var i = 0; i < str.length; ++i) {
bytes.push(str.charCodeAt(i));
}
// use socket.io
var io = require('socket.io').listen(server);
// define interactions with client
io.sockets.on('connection', function(socket){
//send data to client
setInterval(function(){
socket.emit('date', {'date': new Date()});
}, 1000);
//recieve client data
socket.on('client_data', function(data){
var spawn = require('child_process').spawn;
console.log('pre-spawned');
spawn(data.cmd, data.args, {});
setTimeout(function() {
console.log('hello world!');
}, 1000);
var aptIO = require('socket.io-client');
var router = require('socket.io-events')();
var socket2 = aptIO.connect('localhost:8002', {reconnect: true});
router.on('connection', function(s){
//send data to client
console.log('apt');
router.on('*', function(sock, args, next){
var name = args.shift(), msg = args.shift();
console.log(name + " " + JSON.stringify(msg));
sock.emit(bytes);
io.sockets.emit('msg', {'msg': JSON.stringify(msg)})
next();
});
s.emit(bytes);
});
console.log('spawned');
// getting runtime exceptions here...have tried various things...
socket2.use(router);
});
});
With the help from JGreenwell, I was able to resolve me issue.
I ended up having the node server communicate to the client html page via socket.io connection for messages. The node server would launch the cmd line executable providing it the port to connect to which is different from the socket.io port used.
Once started, the executable would communicate with the server via the net module. The server would just pass the information on to the socket.io connection. the js in the html page knows how to parse the message in order to increment the progress bar and list the messages in a text area control.
I took it even further by having the messages be broadcast-ed to multiple clients on the socket.io connection.
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.