websockets seems broken in 1.32.4 after merging #18587

[github-enetrino-com]

perf(ext/websocket): replace tokio_tungstenite server with fastwebsockets #18587

The above commit seems to break websockets.

Symptom: websocket sends do not go through until new messages arrive to the connection.

It's easy to reproduce with example close to the one from https://medium.com/deno-the-complete-reference/native-web-sockets-client-server-in-deno-928678a65cf2 replacing prompts to input text with setTimeout with sending ping-pongs.

//chat_server.ts

import { serve } from "https://deno.land/std/http/mod.ts";
function logError(msg: string) {
  console.log(msg);
  Deno.exit(1);
}
function handleConnected() {
  console.log("Connected to client ...");
}
function handleMessage(ws: WebSocket, data: string) {
  console.log("CLIENT >> " + data);
  setTimeout(()=>ws.send('pong'),2000);
  // const reply = prompt("Server >> ") || "No reply";
  // if (reply === "exit") {
  //   return ws.close();
  // }
  // ws.send(reply as string);
}
function handleError(e: Event | ErrorEvent) {
  console.log(e instanceof ErrorEvent ? e.message : e.type);
}
async function reqHandler(req: Request) {
  if (req.headers.get("upgrade") != "websocket") {
    return new Response(null, { status: 501 });
  }
  const { socket: ws, response } = Deno.upgradeWebSocket(req);
  ws.onopen = () => handleConnected();
  ws.onmessage = (m) => handleMessage(ws, m.data);
  ws.onclose = () => logError("Disconnected from client ...");
  ws.onerror = (e) => handleError(e);
  return response;
}
console.log("Waiting for client ...");
serve(reqHandler, { port: 8001 });

//chat_client.ts

function logError(msg: string) {
  console.log(msg);
  Deno.exit(1);
}
function handleConnected(ws: WebSocket) {
  console.log("Connected to server ...");
  handleMessage(ws, "Welcome!");
}
function handleMessage(ws: WebSocket, data: string) {
  console.log("SERVER >> " + data);
  setTimeout(()=>ws.send('ping'),2000);
  // const reply = prompt("Client >> ") || "No reply";
  // if (reply === "exit") {
  //   return ws.close();
  // }
  // ws.send(reply as string);
}
function handleError(e: Event | ErrorEvent) {
  console.log(e instanceof ErrorEvent ? e.message : e.type);
}
console.log("Connecting to server ...");
try {
  const ws = new WebSocket("ws://localhost:8001");
  ws.onopen = () => handleConnected(ws);
  ws.onmessage = (m) => handleMessage(ws, m.data);
  ws.onclose = () => logError("Disconnected from server ...");
  ws.onerror = (e) => handleError(e);
} catch (err) {
  logError("Failed to connect to server ... exiting");
}

This example sends ping-pongs every 2 seconds on 1.32.3, but stalls on 1.32.4

[etodanik]

Yes, I can confirm! 1.32.4 wreaked complete havoc on our test suite (for a websocket based server project)

[littledivy]

This is fixed on main. You can either upgrade to canary or downgrade to 1.32.3. Duplicate of #18715 #18700