I'm in the process of trying to get an application which I'd built on the old OpenShift Online 2 free service up and running on the new OpenShift Online 3 Starter, and I'm having a bit of trouble.
The application uses websocket, and in the old system all that was required was for the client to connect to my server on port 8443 (which was automatically routed to my server). That doesn't seem to work in the new setup however - the connection just times out - and I haven't been able to find any documentation about using websocket in the new system.
My first thought was that I needed an additional rout, but 8080 is the only port option available for routing as far as I can see.
The app lives here, and the connection is made on line 21 of this script with the line:
this.socket = new WebSocket( 'wss://' + this.server + ':' + this.port, 'tabletop-protocol' );
Which becomes, in practice:
this.socket = new WebSocket( 'wss://production-instanttabletop.7e14.starter-us-west-2.openshiftapps.com:8443/', 'tabletop-protocol' );
On the back end, the server setup is unchanged from what I had on OpenShift 2, aside from updating the IP and port lookup from env as needed, and adding logging to help diagnose the issues I've been having.
For reference, here's the node.js server code (with the logic trimmed out):
var http = require( "http" );
var ws = require( "websocket" ).server;
// Trimmed some others used by the logic...
var ip = process.env.IP || process.env.OPENSHIFT_NODEJS_IP || '0.0.0.0';
var port = process.env.PORT || process.env.OPENSHIFT_NODEJS_PORT || 8080;
/* FILE SERVER */
// Create a static file server for the client page
var pageHost = http.createServer( function( request, response ){
// Simple file server that seems to be working, if a bit slowly
// ...
} ).listen( port, ip );
/* WEBSOCKET */
// Create a websocket server for ongoing communications
var wsConnections = [];
wsServer = new ws( { httpServer: pageHost } );
// Start listening for events on the server
wsServer.on( 'request', function( request ){
// Server logic for the app, but nothing in here ever gets hit
// ...
} );
In another question it was suggested that nearly anything - including this -
could be related to the to the ongoing general issues with US West 2, but other related problems I was experiencing seem to have cleared, and that issue has been posted for a week with no update, so I figured I'd dig deeper into this on the assumption that it's something I'm doing wrong instead of them.
Anyone know more about this and what I need to do to make it work?
Related
I have a local Node.js app on port localhost:3000. I'm using node-osc to message to MaxMSP. My code checks every 2 seconds if there is a reason to send the message (this is related to machine learning and webcam). 95 % of the time this works fine; OSC message might be sent now, then after 2 minutes, then after 10 seconds etc.
However, sometimes the OSC messaging goes crazy by sending a message every two seconds, despite my webcam and machine learning classifications staying the same. If there are no triggering changes, no messages should be sent. I have been thinking if this could be related to the fact that I sometimes change the location and respective IP address where my app functions. Could the system become unstable when switching between two IP addresses? I don't (yet at least) have proof that the "overheating" would come straight after changing the IP address.
Combining OSC with Node.js is new to me so I'm happy for any insights regarding the problem.
Some snippets:
server.js
const express = require("express");
var cors = require('cors');
const app = express();
let broadcaster;
const port = process.env.PORT || 3000;
const http = require("http");
const server = http.createServer(app);
const io = require("socket.io")(server);
const { Client, Message } = require('node-osc');
const client = new Client('xxx.xxx.x.x', 5000); // this IP I keep changing
socket.on("param", function(data) {
console.log(data);
let address = data.address;
client.send(address, data.val);
});
broadcast.js
if (newLabel== "a human" && newLabel !==oldLabel){ // checks this + other changes every 2 seconds
socket.emit("human");
sendParam ("/sound", 4);
}
function sendParam(adr, val) {
let data = {
address: adr,
val: val
};
socket.emit('param', data)
}
I am working with the express and socket.io libraries of Node.js on the same server, listening on the same port. I would like to use the cluster module to support round-robin load balancing, but I want the load-balancing behavior for express and socket.io to be different. The behavior is as follows:
Incoming connections for HTTP/S should connect to any single worker
Incoming connections for WS/S should connect to a specific worker, based on a cookie value---more broadly, based on a value
Are there any available libraries to accomplish my desired behaviors? If not, how should I go about accomplishing these behaviors?
There's a bunch of ways you could do this. I'm gonna link you to this guide on using redis as a pub sub but also I'll give you a super short overview of what it could look like.
So spawn two clusters at start up, or however many you want..
var aWorker = cluster.fork();
var bWorker = cluster.fork();
then you need to set them up to listen on their respective ports, so using the net module:
var server1 = require('net').createServer([options], function( connection ) {
aWorker.send( 'ConnectionEvent' , connection );
}).listen(80); //HTTP/WS
var server2 = require('net').createServer([options], function( connection ) {
bWorker.send( 'ConnectionEvent' , connection );
}).listen(443); //HTTPS/WSS
In your cluster process:
var app_server = require('express')().listen( 0, 'localhost' );
var io = require('socket.io')(app_server);
io.adapter(require('socket.io-redis')({ host: '127.0.0.1', port: **REDIS PORT** });
io.on('connection', function (socket) {
//Rest of your io server code
...
process.on( 'message' , function( message, connection ) {
if( connection && message === 'ConnectionEvent' ) {
app_server.emit( 'connection', connection );
connection.resume();
}
}
I believe the room function of Socket.io would accomplish what you're trying to do in your second point rather than relying on creating new worker tasks. That's just my opinion though.
I am trying to deploy my nodejs app on heroku. I cannot get the websocket connection to establish. I have read everything I could find, tried every example and none of them seem to work for me.
I when I try to open my page "heroku open", nodejs is correctly giving me the html file. However, the websocket 'ws' connection never establishes.
My server.js has these configurations:
var pport = process.env.PORT || 5000;
server.listen(pport, function(err) {
if(!err) { console.log("Listening on port " + pport); }
});
Side Note
When I check "heroku logs", I find that the port my app is running on is a random 5 digit number. ( like 28896, 53365, etc.) It never actually runs on the second half || 5000.
But the thing is, in order for my game.html file to establish a websocket connection, it needs to know what port.
I have tried the following client configurations, none have worked:
1)
var host = location.origin.replace(/^http/, 'ws');
this.connection = new WebSocket(host);
2)
var host = location.origin.replace(/^http/, 'ws');
host = host + ":5000";
this.connection = new WebSocket(host);
3)
this.connection = new WebSocket('ws://infinite-earth-7708.herokuapp.com/');
I have also done what their website said, and attempted to use the following after deploying my app:
heroku config:add NODE_ENV=production
Please advise
Well I figured it out. Here is what you should know:
I did not change my server configurations from my original post.
My client configurations looked like this:
var host = location.origin.replace(/^http/, 'ws');
this.connection = new WebSocket(host);
But here is the kicker.
On the terminal I used the following command:
heroku labs:enable websockets
And voila, it works! I hope this helps someone.
I'm a nooby mobile developer trying to take advantage of cloudfoundry's service to run my server to handle some chats and character movements.
I'm using Noobhub to achieve this (TCP connection between server and client using Node.js and Corona SDK's TCP connection API)
So basically I'm trying a non-http TCP connection between Cloudfoundry(Node.js) and my machine(lua).
Link to Noobhub(There is a github repo with server AND client side implementation.
I am doing
Client
...
socket.connect("myappname.cloudfoundry.com", 45234)
...
(45234 is from server's process.env.VCAP_APP_PORT value I retrieved from console output I got through "vmc logs myappname" after running the application.)
Server
...
server.listen(process.env.VCAP_APP_PORT)
When I try to connect, it just times out.
On my local machine, doing
Client
...
socket.connect("localhost",8989)
Server
...
server.listen(8989)
works as expected. It's just on cloudfoundry that it doesn't work.
I tried a bunch of other ways of doing this such as setting the client's port connection to 80 and a bunch of others. I saw a few resources but none of them solved it.
I usually blow at asking questions so if you need more information, please ask me!
P.S.
Before you throw this link at me with an angry face D:< , here's a question that shows a similar problem that another person posted.
cannot connect to TCP server on CloudFoundry (localhost node.js works fine)
From here, I can see that this guy was trying to do a similar thing I was doing.
Does the selected answer mean that I MUST use host header (i.e. use http protocol) to connect? Does that also mean cloudfoundry will not support a "TRUE" TCP socket much like heroku or app fog?
Actually, process.env.VCAP_APP_PORT environment variable provides you the port, to which your HTTP traffic is redirected by the Cloud Foundry L7 router (nginx) based on the your apps route (e.g. nodejsapp.vcap.me:80 is redirected to the process.env.VCAP_APP_PORT port on the virtual machine), so you definitely should not use it for the TCP connection. This port should be used to listen HTTP traffic. That is why you example do work locally and do not work on Cloud Foundry.
The approach that worked for me is to listen to the port provided by CF with an HTTP server and then attach Websocket server (websocket.io in my example below) to it. I've created sample echo server that works both locally and in the CF. The content of my Node.js file named example.js is
var host = process.env.VCAP_APP_HOST || "localhost";
var port = process.env.VCAP_APP_PORT || 1245;
var webServerApp = require("http").createServer(webServerHandler);
var websocket = require("websocket.io");
var http = webServerApp.listen(port, host);
var webSocketServer = websocket.attach(http);
function webServerHandler (req, res) {
res.writeHead(200);
res.end("Node.js websockets.");
}
console.log("Web server running at " + host + ":" + port);
//Web Socket part
webSocketServer.on("connection", function (socket) {
console.log("Connection established.");
socket.send("Hi from webSocketServer on connect");
socket.on("message", function (message) {
console.log("Message to echo: " + message);
//Echo back
socket.send(message);
});
socket.on("error", function(error){
console.log("Error: " + error);
});
socket.on("close", function () { console.log("Connection closed."); });
});
The dependency lib websocket.io could be installed running npm install websocket.io command in the same directory. Also there is a manifest.yml file which describes CF deploy arguments:
---
applications:
- name: websocket
command: node example.js
memory: 128M
instances: 1
host: websocket
domain: vcap.me
path: .
So, running cf push from this directory deployed app to my local CFv2 instance (set up with the help of cf_nise_installer)
To test this echo websocket server, I used simple index.html file, which connects to server and sends messages (everything is logged into the console):
<!DOCTYPE html>
<head>
<script>
var socket = null;
var pingData = 1;
var prefix = "ws://";
function connect(){
socket = new WebSocket(prefix + document.getElementById("websocket_url").value);
socket.onopen = function() {
console.log("Connection established");
};
socket.onclose = function(event) {
if (event.wasClean) {
console.log("Connection closed clean");
} else {
console.log("Connection aborted (e.g. server process killed)");
}
console.log("Code: " + event.code + " reason: " + event.reason);
};
socket.onmessage = function(event) {
console.log("Data received: " + event.data);
};
socket.onerror = function(error) {
console.log("Error: " + error.message);
};
}
function ping(){
if( !socket || (socket.readyState != WebSocket.OPEN)){
console.log("Websocket connection not establihed");
return;
}
socket.send(pingData++);
}
</script>
</head>
<body>
ws://<input id="websocket_url">
<button onclick="connect()">connect</button>
<button onclick="ping()">ping</button>
</body>
</html>
Only thing to do left is to enter server address into the textbox of the Index page (websocket.vcap.me in my case), press Connect button and we have working Websocket connection over TCP which could be tested by sending Ping and receiving echo. That worked well in Chrome, however there were some issues with IE 10 and Firefox.
What about "TRUE" TCP socket, there is no exact info: according to the last paragraph here you cannot use any port except 80 and 443 (HTTP and HTTPS) to communicate with your app from outside of Cloud Foundry, which makes me think TCP socket cannot be implemented. However, according to this answer, you can actually use any other port... It seems that some deep investigation on this question is required...
"Cloud Foundry uses an L7 router (ngnix) between clients and apps. The router needs to parse HTTP before it can route requests to apps. This approach does not work for non-HTTP protocols like WebSockets. Folks running node.js are going to run into this issue but there are no easy fixes in the current architecture of Cloud Foundry."
- http://www.subbu.org/blog/2012/03/my-gripes-with-cloud-foundry
I decided to go with pubnub for all my messaging needs.
I'm building a settings manager for my http server. I want to be able to change settings without having to kill the whole process. One of the settings I would like to be able to change is change the port number, and I've come up with a variety of solutions:
Kill the process and restart it
Call server.close() and then do the first approach
Call server.close() and initialize a new server in the same process
The problem is, I'm not sure what the repercussions of each approach is. I know that the first will work, but I'd really like to accomplish these things:
Respond to existing requests without accepting new ones
Maintain data in memory on the new server
Lose as little uptime as possible
Is there any way to get everything I want? The API for server.close() gives me hope:
server.close(): Stops the server from accepting new connections.
My server will only be accessible by clients I create and by a very limited number of clients connecting through a browser, so I will be able to notify them of a port change. I understand that changing ports is generally a bad idea, but I want to allow for the edge-case where it is convenient or possibly necessary.
P.S. I'm using connect if that changes anything.
P.P.S. Relatively unrelated, but what would change if I were to use UNIX server sockets or change the host name? This might be a more relevant use-case.
P.P.P.S. This code illustrates the problem of using server.close(). None of the previous servers are killed, but more are created with access to the same resources...
var http = require("http");
var server = false,
curPort = 8888;
function OnRequest(req,res){
res.end("You are on port " + curPort);
CreateServer(curPort + 1);
}
function CreateServer(port){
if(server){
server.close();
server = false;
}
curPort = port;
server = http.createServer(OnRequest);
server.listen(curPort);
}
CreateServer(curPort);
Resources:
http://nodejs.org/docs/v0.4.4/api/http.html#server.close
I tested the close() function. It seems to do absolute nothing. The server still accepts connections on his port. restarting the process was the only way for me.
I used the following code:
var http = require("http");
var server = false;
function OnRequest(req,res){
res.end("server now listens on port "+8889);
CreateServer(8889);
}
function CreateServer(port){
if(server){
server.close();
server = false;
}
server = http.createServer(OnRequest);
server.listen(port);
}
CreateServer(8888);
I was about to file an issue on the node github page when I decided to test my code thoroughly to see if it really is a bug (I hate filing bug reports when it's user error). I realized that the problem only manifests itself in the browser, because apparently browsers do some weird kind of HTTP request keep alive thing where it can still access dead ports because there's still a connection with the server.
What I've learned is this:
Browser caches keep ports alive unless the process on the server is killed
Utilities that do not keep caches by default (curl, wget, etc) work as expected
HTTP requests in node also don't keep the same type of cache that browsers do
For example, I used this code to prove that node http clients don't have access to old ports:
Client-side code:
var http = require('http'),
client,
request;
function createClient (port) {
client = http.createClient(port, 'localhost');
request = client.request('GET', '/create');
request.end();
request.on('response', function (response) {
response.on('end', function () {
console.log("Request ended on port " + port);
setTimeout(function () {
createClient(port);
}, 5000);
});
});
}
createClient(8888);
And server-side code:
var http = require("http");
var server,
curPort = 8888;
function CreateServer(port){
if(server){
server.close();
server = undefined;
}
curPort = port;
server = http.createServer(function (req, res) {
res.end("You are on port " + curPort);
if (req.url === "/create") {
CreateServer(curPort);
}
});
server.listen(curPort);
console.log("Server listening on port " + curPort);
}
CreateServer(curPort);
Thanks everyone for the responses.
What about using cluster?
http://learnboost.github.com/cluster/docs/reload.html
It looks interesting!