Can't close the server after upgrading a connection to Websocket

[Andrepuel]

Code to reproduce the issue:

import { Application, Context } from 'https://deno.land/x/oak@v6.4.1/mod.ts';

const app = new Application();

app.use(async (ctx) => {
    console.log('upgrading');
    const socket = await ctx.upgrade();
    console.log('upgraded');
});

const controller = new AbortController();

const listening = app.listen({ port: 8000, signal: controller.signal });
await new Promise((ok) => setTimeout(ok, 100));

const ws = new WebSocket("ws://127.0.0.1:8000");
await new Promise<void>((ok, err) => {
    ws.onopen = () => ok();
    ws.onerror = (e) => {
      console.error(e);
      ok();
    }
});
await new Promise((ok) => setTimeout(ok, 500));
ws.close();

await new Promise((ok) => setTimeout(ok, 500));
controller.abort();
console.log('aborting');

await Promise.all([
    listening,
    new Promise((_, err) => setTimeout(() => err(new Error("stuck")), 1000))
]);

[Andrepuel]

Looks like the listen() promise is stuck in the Server async iterator. Even after an connection is upgraded to WebSocket, it will still be handled by the iterator, waiting for a deferred promise called done.

[Andrepuel]

By doing the following workaround, I've managed to end the listening promise:

import { Application, Context } from 'https://deno.land/x/oak@v6.4.1/mod.ts';

const app = new Application();

app.use(async (ctx) => {
    console.log('upgrading');
    const socket = await ctx.upgrade();
    // <---------------------------------            Workaround, force untracking this connection
    ctx.request.serverRequest.done.resolve(new Error('force untrack'));
    console.log('upgraded');
});

const controller = new AbortController();

const listening = app.listen({ port: 8000, signal: controller.signal });
await new Promise((ok) => setTimeout(ok, 100));

const ws = new WebSocket("ws://127.0.0.1:8000");
await new Promise<void>((ok, err) => {
    ws.onopen = () => ok();
    ws.onerror = (e) => {
    console.error(e);
    ok();
    }
});
await new Promise((ok) => setTimeout(ok, 500));
ws.close();

await new Promise((ok) => setTimeout(ok, 500));
controller.abort();
console.log('aborting');

await Promise.all([
    listening,
    new Promise((_, err) => setTimeout(() => err(new Error("stuck")), 1000))
]);

However, the main process is still stuck. There is an async op that is leaking. By debugging the async op's I've figured out that a op named "ws next event" never returns. Even after the websocket is closed.

[Andrepuel]

The second problem (stuck after listening finishes) is happening on the client side, not related to OAK.

https://github.com/denoland/deno/issues/7457