server.js

const { WebSocketServer } = require('ws');

const ws = new WebSocketServer({ port: 4444 });

let clients = []

ws.on('connection', (ws, req) => {
  const parts = req.url.split('/');
  const name = parts[parts.length - 1].trim();

  clients.push({ ws, name });

  ws.send(`Welcome ${name}!`);

  ws.on('close', () => {
    clients = clients.filter(client => client.name !== name);
  });

  ws.on('error', console.error);

  ws.on('message', data => {
    clients
      .filter(client => client.name !== name)
      .forEach(client => client.ws.send(data));
  });
});