Node net.Socket emit data to all connected clients - node.js

Question

guys, I'm trying to make simple TCP server with net.Socket package I'm using the express framework.
The behaviour that Im trying to achieve is when user enters specific route to emmit data to all connected clients, doesn anyone now how could I achieve this ??
Here is my sample code:
const express = require('express');
const app = express();
const cors = require('cors');
const bodyParser = require('body-parser');
const net = require('net');
const PORT = 5000;
let connection;
const server = net.createServer((socket) => {
console.log('CONNECTED: ' + socket.remoteAddress +':'+ socket.remotePort);
connection = socket;
});
app.use(cors());
app.use(bodyParser.json());
app.get('/', (request, response) => {
response.send('VMS server');
});
app.post('/contact', (req, res) => {
const data = { hello: 'hello' }
connection.write(data);
res.send({ data: 'data emmited' })
});
app.listen(PORT, () => {
console.log(`Server running at: http://localhost:${PORT}/`);
});
server.listen(1337, function() {
console.log("Listening on 1337");
});
The problem m having here is that data is gettings emitted multiple times, because Im assigning current socket to connection variable.
Is there any other way how I can do this, could I use server variable to emit to all connected clients somehow ?

Answer 1

Ok, managed to solve it. Here are steps on how I solved it - create an array of clients, & when a client connected to the server , push that socket to client array when disconnected remove that item from the array... And to emit data to all clients, I created a broadcast method where I loop through client array, and call the emit method of each socket & send data.
Here is a sample code:
const express = require('express');
const app = express();
const cors = require('cors');
const bodyParser = require('body-parser');
const net = require('net');
const PORT = 5000;
let sockets = []; // array of sockets
// emmit data to all connected clients
const broadcast = (msg) => {
//Loop through the active clients object
sockets.forEach((client) => {
client.write(msg);
});
};
const server = net.createServer((socket) => {
console.log('CONNECTED: ' + socket.remoteAddress +':'+ socket.remotePort);
sockets.push(socket);
socket.on('end', () => {
console.log('DISCONNECTED: ');
// remove the client for list
let index = sockets.indexOf(socket);
if (index !== -1) {
console.log(sockets.length);
sockets.splice(index, 1);
console.log(sockets.length);
}
});
});
app.use(cors());
app.use(bodyParser.json());
app.get('/', (request, response) => {
response.send('VMS server');
});
app.post('/contact', (req, res) => {
const data = { hello: 'hello' }
broadcast(data); //emit data to all clients
res.send({ data: 'data emmited' })
});
app.listen(PORT, () => {
console.log(`Server running at: http://localhost:${PORT}/`);
});
server.listen(1337, function() {
console.log("Listening on 1337");
});