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How to receive data in real time from TCP socket using PHP or JS? [duplicate]

I have a vb.net application that opens a socket and listens on it.
I need to communicate via this socket to that application using a javascript running on a browser. That is i need to send some data on this socket so that the app which is listening on this socket can take that data, do some stuff using some remote calls and get some more data and put it back on the socket that my javascript needs to read and print it in the browser.
Ive tried, socket.io, websockify but none have proved to be useful.
Hence the question, is what i am trying even possible? Is there a way that a javascript running in a browser can connect to a tcp socket and send some data and listen on it for some more data response on the socket and print it to the browser.
If this is possible can some one point me in the right direction as to which would help me establish the goal.

As for your problem, currently you will have to depend on XHR or websockets for this.
Currently no popular browser has implemented any such raw sockets api for javascript that lets you create and access raw sockets, but a draft for the implementation of raw sockets api in JavaScript is under-way. Have a look at these links:
http://www.w3.org/TR/raw-sockets/
https://developer.mozilla.org/en-US/docs/Web/API/TCPSocket
Chrome now has support for raw TCP and UDP sockets in its ‘experimental’ APIs. These features are only available for chrome apps and, although documented, are hidden for the moment. Having said that, some developers are already creating interesting projects using it, such as this IRC client.
To access this API, you’ll need to enable the experimental flag in your extension’s manifest. Using sockets is pretty straightforward, for example:
chrome.experimental.socket.create('tcp', '127.0.0.1', 8080, function(socketInfo) {
chrome.experimental.socket.connect(socketInfo.socketId, function (result) {
chrome.experimental.socket.write(socketInfo.socketId, "Hello, world!");
});
});

This will be possible via the navigator interface as shown below:
navigator.tcpPermission.requestPermission({remoteAddress:"127.0.0.1", remotePort:6789}).then(
() => {
// Permission was granted
// Create a new TCP client socket and connect to remote host
var mySocket = new TCPSocket("127.0.0.1", 6789);
// Send data to server
mySocket.writeable.write("Hello World").then(
() => {
// Data sent sucessfully, wait for response
console.log("Data has been sent to server");
mySocket.readable.getReader().read().then(
({ value, done }) => {
if (!done) {
// Response received, log it:
console.log("Data received from server:" + value);
}
// Close the TCP connection
mySocket.close();
}
);
},
e => console.error("Sending error: ", e)
);
}
);
More details are outlined in the w3.org tcp-udp-sockets documentation.
http://raw-sockets.sysapps.org/#interface-tcpsocket
https://www.w3.org/TR/tcp-udp-sockets/
Another alternative is to use Chrome Sockets
Creating connections
chrome.sockets.tcp.create({}, function(createInfo) {
chrome.sockets.tcp.connect(createInfo.socketId,
IP, PORT, onConnectedCallback);
});
Sending data
chrome.sockets.tcp.send(socketId, arrayBuffer, onSentCallback);
Receiving data
chrome.sockets.tcp.onReceive.addListener(function(info) {
if (info.socketId != socketId)
return;
// info.data is an arrayBuffer.
});
You can use also attempt to use HTML5 Web Sockets (Although this is not direct TCP communication):
var connection = new WebSocket('ws://IPAddress:Port');
connection.onopen = function () {
connection.send('Ping'); // Send the message 'Ping' to the server
};
http://www.html5rocks.com/en/tutorials/websockets/basics/
Your server must also be listening with a WebSocket server such as pywebsocket, alternatively you can write your own as outlined at Mozilla

ws2s project is aimed at bring socket to browser-side js. It is a websocket server which transform websocket to socket.
ws2s schematic diagram
code sample:
var socket = new WS2S("wss://ws2s.feling.io/").newSocket()
socket.onReady = () => {
socket.connect("feling.io", 80)
socket.send("GET / HTTP/1.1\r\nHost: feling.io\r\nConnection: close\r\n\r\n")
}
socket.onRecv = (data) => {
console.log('onRecv', data)
}

See jsocket. Haven't used it myself. Been more than 3 years since last update (as of 26/6/2014).
* Uses flash :(
From the documentation:
<script type='text/javascript'>
// Host we are connecting to
var host = 'localhost';
// Port we are connecting on
var port = 3000;
var socket = new jSocket();
// When the socket is added the to document
socket.onReady = function(){
socket.connect(host, port);
}
// Connection attempt finished
socket.onConnect = function(success, msg){
if(success){
// Send something to the socket
socket.write('Hello world');
}else{
alert('Connection to the server could not be estabilished: ' + msg);
}
}
socket.onData = function(data){
alert('Received from socket: '+data);
}
// Setup our socket in the div with the id="socket"
socket.setup('mySocket');
</script>

In order to achieve what you want, you would have to write two applications (in either Java or Python, for example):
Bridge app that sits on the client's machine and can deal with both TCP/IP sockets and WebSockets. It will interact with the TCP/IP socket in question.
Server-side app (such as a JSP/Servlet WAR) that can talk WebSockets. It includes at least one HTML page (including server-side processing code if need be) to be accessed by a browser.
It should work like this
The Bridge will open a WS connection to the web app (because a server can't connect to a client).
The Web app will ask the client to identify itself
The bridge client sends some ID information to the server, which stores it in order to identify the bridge.
The browser-viewable page connects to the WS server using JS.
Repeat step 3, but for the JS-based page
The JS-based page sends a command to the server, including to which bridge it must go.
The server forwards the command to the bridge.
The bridge opens a TCP/IP socket and interacts with it (sends a message, gets a response).
The Bridge sends a response to the server through the WS
The WS forwards the response to the browser-viewable page
The JS processes the response and reacts accordingly
Repeat until either client disconnects/unloads
Note 1: The above steps are a vast simplification and do not include information about error handling and keepAlive requests, in the event that either client disconnects prematurely or the server needs to inform clients that it is shutting down/restarting.
Note 2: Depending on your needs, it might be possible to merge these components into one if the TCP/IP socket server in question (to which the bridge talks) is on the same machine as the server app.

The solution you are really looking for is web sockets. However, the chromium project has developed some new technologies that are direct TCP connections TCP chromium

JavaScript - ReferenceError: WebSocket is not defined

Focusing on the client side API only (because each server side language will have its own API), the following snippet opens a connection, creates event listeners for connect, disconnect, and message events, sends a message back to the server, and closes the connection using WebSocket.
// Create a socket instance
var socket = new WebSocket('ws://localhost:3000');
// Open the socket
socket.onopen = function(event) {
// Send an initial message
socket.send('I am the client and I\'m listening!');
// Listen for messages
socket.onmessage = function(event) {
console.log('Client received a message',event);
};
// Listen for socket closes
socket.onclose = function(event) {
console.log('Client notified socket has closed',event);
};
// To close the socket....
socket.close()
};
But I am getting an error on executing above snippet:
ReferenceError: WebSocket is not defined
I have gone through various links like https://davidwalsh.name/websocket, on how to implement WebSockets. But none of them are importing any npm package.
Question: So, how to implement WebSockets (client side AngularJS)? What am I missing here?

Try
const WebSocket = require('ws');
var socket = new WebSocket('ws://localhost:3000');
Then
npm i ws
and retry. It's work with my case

I'm leaving this here for people having trouble with the #stomp/stompjs package in a node app.
Add this line:
Object.assign(global, { WebSocket: require('ws') });
also, don't forget to npm install ws

The code you're referencing in your question is client-side code. WebSocket is available directly in browsers.
For your Node.js server-side code, look at the ws NPM package.
So, how to implement WebSockets (client side) on NodeJS?
You don't. Node.js is server-side, not client-side.

When you are trying to run JavaScript, usually, you run it either in Browser or in NodeJS.
Browser and NodeJS are different JavaScript runtime.
WebSocket itself is a application layer protocol, you need to use API to employ it.
Currently(05-Dec-2019),
most browsers support WebSocket API for developer to use WebSocket.
NodeJS does not provide any OOTB API for developer to use WebSocket, you need 3rd lib to use WebSocket (e.g. https://github.com/websockets/ws).
The example you followed is using WebSocket API in browser.
Hope it helps.

Send data from server through HTML file in nodejs

My goal is to send text left or right triggered from my html file to all clients connected to server (my nodejs server file). I tried many online solutions but i am not able to understand and some of them not working, because am not regular nodejs programmer.
I have created web app in html with two buttons left and right. When i click left button on html file my all connected clients should get text "left". I also created server.js nodejs file which is perfectly communicating with all clients. Problem is how can i get communication between html file and server file.
Note : html file is server side trigger point not client.
server.js
var net = require('net');
var HOST = '127.0.0.1';
var PORT = 8888;
net.createServer(function (sock) {
console.log('connected : ' + sock.remoteAddress + ':'+sock.remotePort);
var ip = sock.remoteAddress.split(':')[3];
console.log(ip);
sock.write('hello client you are connected with server 10.0.0.19...');
sock.on('data', function (data) {
console.log('DATA '+ sock.remoteAddress+' - '+data);
sock.write('you said : '+data);
});
function sendto(result) { //tried call from html file
console.log('sent '+result);
sock.write('data : '+result);
}
sock.on('close', function (data) {
console.log('closed');
});
}).listen(PORT);
console.log('server running on '+PORT);
Help me with way to communicate my html file with server.js, but not as client.

Use SSE , server sent events to send a event from your server to all your connections.
From Client :
Whenever you click the left/button you hit a api of your NODE. The same API when hit will publish a SSE to all the clients.
In the Subscriber End ,
var source = new EventSource("/pageTell"); (an API which your server exposes)
source.onmessage = function(event) {
document.getElementById("result").innerHTML += event.data + "<br>";
};

HTTP, by default, is a short lived request response connection which is not always connected. Meaning, the server sends out a HTML or related page, and then the connection is disconnected. Based on your use case you need the server to keep the connection open so that all connected clients can be informed of state changes.
For your usecase, you need something like WebSockets (very neatly documented on html5rocks https://www.html5rocks.com/en/tutorials/websockets/basics/). OR if you intend to support older browsers look at socket.io . Socket IO basic sample should be able to help you in achieving your requirements

Use socket.io for this. It has node module as well as client side library.
Implement socket listener on all the clients. Whichever client is listening to the event will receive the data. Emit the data with event name when the button is clicked using the client side javascript of socket io. Check this example out for the same.

Jetty Web Socket Timeout

I am trying to establish a Web Socket Connection using Jetty 9.3.0 RC.
function checkDetails(port) {
var ws = new WebSocket("ws://localhost:9995/application");
ws.onopen = function(event) {
console.log("onopen called...");
}
ws.onerror = function(event){
console.log('onerror called...');
}
ws.onmessage = function(event) {
console.log("onmessage called..." + event.data);
}
ws.onclose = function(event) {
console.log("onclose called..." + port);
console.log(event);
ws.close();
}
}
The code works fine if the port 9995 used for creating the Web Socket connection is not occupied by some other process.
var ws = new WebSocket("ws://localhost:9995/application");
But in case if the port is occupied by some other process, then it keeps on trying to connect with that port until the port is released.
I need to provide a timeout so that if the port does not respond in 3 mins then the Web Socket should release (or stop listening) the port and display a console log.
Please let me know the simplest way to achieve this.

From client side you are connecting to some web socket. If port (9995 in your case) is available to connect to then it means that some program (in server mode) is listening and responding. And does something - answers with some data. So, you can connect to such program if it exists and answers or you cannot if there is no server listener for port 9995. When you say "port is occupied" by some other process that means that this process exist and answers. And this process will respond with whatever it is designed for. So, from client side, all what you do is connect to existing and running process which listens for this port in the server mode. That's it and that's all.
However, if we ignore your comment that OP is only about client side then my first suggestion would be to look on the server configuration and check that it is in multithread mode and can answer and proceed multiple requests at once. What you are describing looks like you have singe thread process which works with only one request and can answer next one when current is finished. That sounds like "process occupied". But since comment insist that we are talking only about client side then this speculation would be unnecessary.

WebSocket not connecting to socket.io

I am using Node.js with socket.io to implement websockets in one of my pages. server.js (what Node.js runs) has this code:
var http = require("http").createServer(),
io = require("socket.io").listen(http);
http.listen(8080);
io.sockets.on("connection", function(socket) {
socket.emit("message", {hello:"world"});
});
And this is the code I'm trying to connect with:
var socket = new WebSocket("ws://92.60.122.235:8080/");
socket.onopen = function() {
alert("Socket has been opened!");
}
When I load the page, nothing happens. I'm using Chrome, and I know websockets are supported. No errors are present in the error console, and if I watch socket.io serving requests from command line I don't see any user connecting.
As far as I know this should work, could anyone explain what could be going wrong?

You need a socket.io client to pass some authentication phases I believe. Try this, and it should work(the client javascript is served by socket.io itself, don't worry about it).
<script src="/socket.io/socket.io.js"></script>
<script>
var socket = io.connect('http://localhost');
socket.on('message', function (data) {
console.log(data);
socket.emit('helloworld', { msg: 'why do you so love to say hello world?' });
});
</script>
From http://socket.io/#faq
Why not just call it WebSocket if the actual WebSocket is not
present and mimick its API?
Socket.IO does more than WebSocket, even
if WebSocket is selected as the transport and the user is browsing
your website with an ultra modern browser. Certain features like
heartbeats, timeouts and disconnection support are vital to realtime
applications but are not provided by the WebSocket API out of the box.
This is akin to jQuery's decision of creating a feature-rich and
simple $.ajax API as opposed to normalizing XMLHttpRequest.

You can download the webpage source code that runs in Chrome, Firefox, and IE (at least) via the blog article "Websocket Server Demonstration" from the High Level Logic Project. The webpage is set up for developers.