I have opened the server.js and the address:http://localhost:8081 on my browser. But then a text "Upgrade Required" appeared at the top left conern of the website.
What is the problem of that? What else do I need to upgrade?
Here is the server.js:
var serialport = require('serialport');
var WebSocketServer = require('ws').Server;
var SERVER_PORT = 8081;
var wss = new WebSocketServer({
port: SERVER_PORT
});
var connections = new Array;
SerialPort = serialport.SerialPort,
portName = process.argv[2],
serialOptions = {
baudRate: 9600,
parser: serialport.parsers.readline('\n')
};
if (typeof portName === "undefined") {
console.log("You need to specify the serial port when you launch this script, like so:\n");
console.log(" node wsServer.js <portname>");
console.log("\n Fill in the name of your serial port in place of <portname> \n");
process.exit(1);
}
var myPort = new SerialPort(portName, serialOptions);
myPort.on('open', showPortOpen);
myPort.on('data', sendSerialData);
myPort.on('close', showPortClose);
myPort.on('error', showError);
function showPortOpen() {
console.log('port open. Data rate: ' + myPort.options.baudRate);
}
function sendSerialData(data) {
if (connections.length > 0) {
broadcast(data);
}
}
function showPortClose() {
console.log('port closed.');
}
function showError(error) {
console.log('Serial port error: ' + error);
}
function sendToSerial(data) {
console.log("sending to serial: " + data);
myPort.write(data);
}
wss.on('connection', handleConnection);
function handleConnection(client) {
console.log("New Connection");
connections.push(client);
client.on('message', sendToSerial);
client.on('close', function () {
console.log("connection closed");
var position = connections.indexOf(client);
connections.splice(position, 1);
});
}
function broadcast(data) {
for (c in connections) {
connections[c].send(data);
}
}
OK, websockets...
The "upgrade required" status marks the start of a websocket handshake. Normally your client sends this first to the WS server. The server answers in a pretty similar manner (details here : https://www.rfc-editor.org/rfc/rfc6455 ), and then proceed to pipe the actual data.
Here, you're opening a connection from your client as regular http, sending a simple GET. What you see on the screen is the server dumbly proceeding with an already corrupted handshake.
That's not how you open a WS client side connection. You don't usually open WS pages from the browser. It ought to be opened from a JavaScript call, such as new WebSocket(uri). So what you want is a regular http server on another port, that serves a page containing the necessary Javascript to open the actual WS connection and do something useful with its data. You'll find a clean example here : http://www.websocket.org/echo.html
Related
So my main webpage example.com is run through cloudflare and has a edge certificate from Origin -> CF Edge (origin cert) and an edge certificate CF Edge -> Client. I'm bypassing this for my websocket by using a subdomain, dt.example.com which uses cloudflare although using this link resolves the origin server address rather than the cloudflare edge server address (which i've found solves some issues for me, or maybe it's counterproductive to use this method?). Anyway, I am using a free ssl certificate for secure websockets -
'use strict';
var https = require('https');
var fs= require('fs');
var express = require('express');
var WebSocket = require('ws');
var server = https.createServer({
cert: fs.readFileSync('../ssl/wss/new/certificate.crt'),
key: fs.readFileSync('../ssl/wss/new/private.pem'),
ca: fs.readFileSync('../ssl/wss/new/ca_bundle.crt')
});
const wss = new WebSocket.Server({server});
wss.on('connection', function connection (ws) {
ws.on('message', function message (msg) {
console.log(msg);
});
});
server.listen(58443, function listening () {
const ws = new WebSocket('wss://dt.example.com:58443', {
rejectUnauthorized: false
});
ws.on('open', function open () {
ws.send('Workin baby');
});
});
-and using a websocket client plugin for chrome allows me to connect to the socket, however i cannot on example.com/webpage where the follow code is:
var ws = new window.WebSocket('wss://dt.example.com:58443/', {
rejectUnauthorized: false
});
ws.on('open', function open () {
ws.send('What\'s crackin?');
});
Although in browser (Chrome) when the client script executes it exits with the following error Uncaught DOMException: Failed to construct 'WebSocket': The subprotocol '[object Object]' is invalid. (on line 1)
I managed to solve this by stumbling across something intriguing in a post elswhere.
Essentially I just moved the rejectUnauthorized into the server code and then retried running on the client and it connected to the server :)
So there are two ways of doing this i'll list out both of them ,for more information you can visit https://www.npmjs.com/package/websocket
Using W3CWebSocket
var ws= require('websocket').w3cwebsocket;
var client = new W3CWebSocket('wss://dt.example.com:58443/'{
rejectUnauthorized: false
}, 'echo-protocol');
client.onerror = function() {
console.log('Connection Error');
};C
client.onopen = function open () {
ws.send('What\'s crackin mate?');
};
client.onclose = function() {
console.log('echo-protocol Client Closed');
};
client.onmessage = function(e) {
if (typeof e.data === 'string') {
console.log("Received: '" + e.data + "'");
}
};
Using a normal websocket client
var WebSocketClient = require('websocket').client;
var client = new WebSocketClient();
client.on('connectFailed', function(error) {
console.log('Connect Error: ' + error.toString());
});
client.on('connect', function(connection) {
console.log('WebSocket Client Connected');
connection.on('error', function(error) {
console.log("Connection Error: " + error.toString());
});
connection.on('close', function() {
console.log('echo-protocol Connection Closed');
});
connection.on('message', function(message) {
if (message.type === 'utf8') {
console.log("Received: '" + message.utf8Data + "'");
}
});
});
client.connect('ws://localhost:8080/', 'echo-protocol');
You can solve this problem by adding corresponding protocol value in front side to the response header in back-end side with key = "Sec-WebSocket-Protocol".
In your case , you should add a HTTP header with key "Sec-WebSocket-Protocol" and with value "Chat-1.0"
Background: I have a node.js server running on my localhost (call this Server A); and an external server running node.js at https://example.net:3000 (call this Server B). I do not control or have access to Server B (it is a dashboard site for an IoT device in my home), but I need to connect to is using socket.io and emit a specific message.
I can connect to it easily from a flat javascript file (client-side), but need it running server side (ultimate goal is to make it into something I can call with an HTTP request); and examples such as How to connect two node.js servers with websockets? suggest I should be able to use socket.io-client from node.js with nearly the same code to achieve the same results. But when I run the code from node.js, I cannot connect to the socket.
Below is the code that works successfully in flat javascript file. I know it works because I see 'socket connect' in the console, and I can also test for the the socket emit at the end.
var myemail = "email#gmail.com";
var device_id = '12345';
// Create SocketIO instance, connect
var socket = io.connect('https://example.net:3000');
socket.on('connect', function(){
try {
console.log('socket connect');
socket.emit('configure', {email:myemail, deviceid:device_id});
} catch(e) {
console.log(e);
}
});
socket.emit("/" + device_id, "45678");
...and below is the code I cannot get to work when running from my node.js instance. I'd expect a message 'socket connect' in the command line log and get nothing.
var express=require('express');
var http=require('http');
var app=express();
var server = http.createServer(app);
//Variables
var myemail = "email#gmail.com";
var device_id = '12345';
var io = require('socket.io-client');
var socket = io.connect('https://example.net:3000');
//Connect listener
socket.on('connect', function(){
try {
console.log('socket connect');
socket.emit('configure', {email:myemail, deviceid:device_id});
} catch(e) {
console.log(e);
}
});
socket.emit("/" + device_id, "45678");
Any ideas?
UPDATE
Ran debug utility, results included as linked image below. Key thing I see is that engine.io tries to do an xhr poll, and gets a 503 response back from the server. (Obviously not a true 'temporary error' with the server as again, this all works from running client-side js in chrome).
debugging output image link
Solved this - issue was that the server I was connecting to required use of https, so I needed to add
{secure: true, rejectUnauthorized: false}
after the url to connect to.
Full working example:
const myemail = email#email.com;
const device_id = 12345;
io = require('socket.io-client');
var socket = io.connect('https://server.net:3000',{secure: true, rejectUnauthorized: false});
function doStuff(){
//Listener
socket.on('connect', function(){
try {
console.log('socket connect');
socket.emit('configure', {email:myemail, deviceid:device_id});
} catch(e) {
console.log(e);
}
});
socket.emit("/" + device_id, "003021");
}
doStuff();
I think the line causing the issue is :
var socket = io.connect('https://example.net:3000');
I managed to make a working example using this code :
const myemail = "email#gmail.com";
const device_id = '12345';
var socket = require('socket.io-client')('https://example.net:3000');
socket.on('connect', function(){
try{
console.log('socket connect');
socket.emit('configure', {email:myemail, deviceid:device_id});
}catch(e){ console.log(e); }
});
I am trying to connect between js client and python server in chrome extension platform, but getting error in the connection establishment.
It is important to note that the code worked in cmd test, but when I tried to make the connection in the chrome extension, it gets an error. So if someone had already deal with something similar, please check the code and help me to figure what is wrong with it.
I used serversocket module.
Here is the server:
clients = []
class MyTCPHandler(socketserver.BaseRequestHandler):
def handle(self):
if self not in clients:
clients.append(self)
self.data = self.request.recv(1024).strip()
if self.data == "":
clients.remove(self)
print(self.data)
arr=self.data.split('~')
result=algo(arr)
self.request.send(result)
if _name_ == "__main__":
HOST, PORT = '127.0.0.1', 6169
server = socketserver.TCPServer((HOST, PORT), MyTCPHandler)
print("hi")
# interrupt the program with Ctrl-C
server.serve_forever()
The alerts and some of the if are for checking
and the client:
var st="password11"+"~"+"www.google.com"+"~"+"1656226256";
//"wss://"+HOST+":"+PORT+"/"
if ('WebSocket' in window){
alert("websocket");
var socket = new WebSocket("wss://127.0.0.1:6169/", ['soap', 'xmpp']);
socket.onopen = function (evt) {
alert("connection opened");
socket.send(st);
};
socket.onmessage = function (evt) {
alert("Message from remote server : "+evt.data);
socket.close();
};
socket.onerror = function (evt) {
alert(evt.data);
};
socket.onclose = function (evt) {
alert("connection closed");
};
}
else {
alert("web socket is not supported")
}
I am in a trouble while coding ssh2 module in my project. I tried to run multiple commands on one terminal for ruling remote Linux system. For example "bc" command provides you a basic calculator and you can run it for basic operations. but that kind of processes need to be awake when you are using (it will accepts two or more input and it will give a response as a result).
I need to create a system like work with websocket and ssh. When a websocket received a command ,ssh node need to execute this message and Module need to send it's response via websocket.send()
I am using Node.js websocket,ssh2 client.
Here my code :
#!/usr/bin/node
var Connection = require('ssh2');
var conn = new Connection();
var command="";
var http = require('http');
var WebSocketServer = require('websocket').server;
var firstcom=true;
conn.on('ready', function() {
console.log('Connection :: ready');
// conn.shell(onShell);
});
var onShell = function(err, stream) {
// stream.write(command+'\n');
stream.on('data', function(data) {
console.log('STDOUT: ' + data);
});
stream.stderr.on('data', function(data) {
console.log('STDERR: ' + data);
});
}
var webSocketsServerPort=5000;
var ssh2ConnectionControl=false;
var server = http.createServer(function (req, res) {
//blahbalh
}).listen(webSocketsServerPort, function() {
console.log((new Date()) + " Server is listening on port:: " + webSocketsServerPort);
});
//console.log((new Date()) + 'server created');
wsServer = new WebSocketServer({
httpServer: server,
// autoAcceptConnections: false
});
wsServer.on('request', function(request) {
console.log((new Date()) + ' Connection from origin ' + request.origin + '.');
var wsconnection = request.accept('echo-protocol', request.origin);
console.log((new Date()) + ' Connection accepted.');
if(!ssh2ConnectionControl){
conn.connect({
host: 'localhost',
port: 22,
username: 'attilaakinci',
password: '1'
});
ssh2ConnectionControl=true;
console.log('SSH Connected.');
}
wsconnection.on('message', function(message) {
if (message.type === 'utf8') {
console.log('Received Message: ' + message.utf8Data);
command=message.utf8Data;
//if(firstcom){
// conn.shell(onShell);
// firstcom=false;
//}else{
conn.exec(message.utf8Data,onShell);
//}
wsconnection.send(message.utf8Data);
}
else{
console.log('Invalid message');
}
});
wsconnection.on('close', function(reasonCode, description) {
console.log((new Date()) + ' Peer ' + wsconnection.remoteAddress + ' disconnected.');
});
});
You should use conn.shell() instead of conn.exec() if you want a real interactive shell. conn.exec() is typically for executing one-liner commands, so it does not persist "shell state" between conn.exec() calls (e.g. working directory, etc.).
You should also be aware of possible limits by your SSH server has set up as far as how many simultaneous shell/exec requests are allowed per connection. I think the default limit for this on OpenSSH's server is 10.
This is an old question but I wanted to provide a alternative method usings sh2shell which wraps ssh2.shell by mscdex, used above. The example below only covers making the ssh connection, running the commands and processing the result.
Using ssh2shel it is possible to run any number of commands sequentually in the context of the previous commands in the same shell session and then return the output for each command (onCommandComplete event) and/or return all session text on disconnection using a callback function.
See the ssh2shell readme for examples and lots of info. There are also tested scripts for working code examples.
var host = {
//ssh2.client.connect options
server: {
host: 120.0.0.1,
port: 22,
userName: username,
password: password
},
debug: false,
//array of commands run in the same session
commands: [
"echo $(pwd)",
command1,
command2,
command3
],
//process each command response
onCommandComplete: function( command, response, sshObj) {
//handle just one command or do it for all of the each time
if (command === "echo $(pwd)"){
this.emit("msg", response);
}
}
};
//host object can be defined earlier and host.commands = [....] set repeatedly later with each reconnection.
var SSH2Shell = require ('ssh2shell');
var SSH = new SSH2Shell(host),
callback = function( sessionText ){
console.log ( "-----Callback session text:\n" + sessionText);
console.log ( "-----Callback end" );
}
SSH.connect(callback)
To see what is happening at process level set debug to true.
I'm using socket.io for realtime communication. When inetrnet is not available for few seconds, then it will connect to server when the connection is establish and then it will immediately trigger event which will log in my clinet. After establishing connection, (i think) my socket.io on server side fire disconnect event after ~one minute (in callback function I log off my client), and that is my problem.
This is my server side. (a have server.js and he run other.js files, in object 'files' a have that files).
server.js :
io = require('socket.io').listen(server);//server listening on 8080 port
io.configure(function () {
io.set('transports', ['websocket', 'xhr-polling']);
io.set('log level', 1);
io.disable('browser client');
});
var files = {
control: null,
terminal: null,
messages: null
};
for (var game in games) {
games[game] = require('./game_modules/' + game + '.js').listen(io, create_waiter(game));
}
require('http').createServer(function (req, res) {
var resultCode = 500;
var resultText = '';
var parts = require('url').parse(req.url, true);
var matches = parts.pathname.match('^/([a-z_-]+)/([a-z_-]+)/$');
if (matches) {
var game = matches[1];
var command = matches[2];
resultText = games[game][command](parts.query);
resultCode = 200;
res.writeHead(resultCode, {'Content-Type': 'text/plain'});
res.end(resultText);
}).listen(8081, "127.0.0.1");
control.js :
var control = module.exports = function() {
};
control.listen = function(io) {
this.server = io.of('/control');
this.onTerminate = onTerminate;
//********************************************************************************
this.server.on('connection', function(socket) {
socket.on('disconnect', function(data) {
console.log(data); //after my client reconnect, disconnect event is triggered, and
//console.log write 'close timeout'
After client reconnect, I do not want trigger disconnect event, or if disconnect event was triggered I want check in callback function: is my client connected and prevent "log off" for my client.
Thanks :)