Working with WebSockets

import { WebSocketServer } from "ws";
const wss = new WebSocketServer({ port: 8080 });
wss.on("connection", (ws) => {
  ws.on("message", (msg) => ws.send(`echo: ${msg}`));
});

ws.on("message", (data, isBinary) => {
  const msg = isBinary ? data : data.toString();
});

function broadcast(data) {
  for (const client of wss.clients) {
    if (client.readyState === client.OPEN) client.send(data);
  }
}

function noop() {}
function alive() { this.isAlive = true; }
wss.on("connection", (ws) => {
  ws.isAlive = true;
  ws.on("pong", alive);
});
const interval = setInterval(() => {
  for (const ws of wss.clients) {
    if (!ws.isAlive) return ws.terminate();
    ws.isAlive = false;
    ws.ping(noop);
  }
}, 30_000);