How can I connect WebSocket listening to one port to Net socket listening to another, using NodeJS? - sockets

Question

This is the approach I tried but not working. I can forward the incoming messages from the WebSocket connection to the NetSocket, but only the first one received by NetSocket arrives to the client behind the WebSocket.
const WebSocket = require('ws');
const wss = new WebSocket.Server({ port: 8080 });
const NetSocket = require('net');
const net = new NetSocket.Socket();
// Web socket
wss.on('connection', function connection(ws) {
console.log((new Date()) + ' Remote connection accepted ' + ws.remoteAddress);
ws.on('message', function incoming(message) {
console.log('Received from remote: %s', message);
net.write(message)
});
ws.on('close', function(){
console.log((new Date()) + ' Remote connection closed');
});
});
// Net socket
net.connect(8745, '127.0.0.1', function() {
console.log((new Date()) + ' Local connection accepted');
});
net.on('data', function(data) {
console.log('Received from local: ' + data);
// Iterate the connected devices to send the broadcast
wss.clients.forEach(function each(c) {
if (c.readyState === WebSocket.OPEN) {
c.send(data);
}
});
});
net.on('close', function() {
console.log('Local connection closed');
});

Answer 1

After a new research I noticed that the problem was in my swift code.
private func setReceiveHandler() {
webSocketTask.receive { result in
defer { self.setReceiveHandler() } // I was missing this line
do {
let message = try result.get()
switch message {
case let .string(text):
print("Received text message: \(text)")
case let .data(data):
So, just adding defer { self.setReceiveHandler() } to my function, it started to work.
Note the defer statement at the start of the receive handler. It calls self.setReceiveHandler() to reset the receive handler on the socket connection to allow it to receive the next message. Currently, the receive handler you set on a socket connection is only called once, rather than every time a message is received. By using a defer statement, you make sure that self.setReceiveHandler is always called before exiting the scope of the receive handler, which makes sure that you always receive the next message from your socket connection.
I've got the information from:
https://www.donnywals.com/real-time-data-exchange-using-web-sockets-in-ios-13/