QUIC/Webtransport: uncaught rejected promise when disconnect / timing out

[hironichu]

Version: Deno 2.2.X
Whenever we run a server and receive connections, the endpoint/listener will respect the time out amount and throw an exception: Error: timed out

This exception comes from the closed method (from my testing..)

Client code :

        const wt = new WebTransport("https://xxxxxx");
        await wt.ready;
        console.log(wt);
        wt.closed.then(() => console.log("Connection closed"));
        //wait 10 second and close the connection
        setTimeout(() => wt.close(), 10000);

Server code :

const cert = Deno.readTextFileSync("cert.pem");
const key = Deno.readTextFileSync("private.pem");

const server = new Deno.QuicEndpoint({
    hostname: "0.0.0.0",
    port: 443,
});
try {
    const listener = server.listen({
        cert,
        key,
        alpnProtocols: ["h3"],
    });
    try {
        console.log("waiting first connection");
        const nextCon = await listener.accept();
        const wt = await Deno.upgradeWebTransport(nextCon);
        await wt.ready;
        console.log("Client connected");
        wt.closed.then(() => {
            console.log("Client closed the connection");
            Deno.exit(0);
        });
    } catch {
        console.log("Something wrong happened");
    }
} catch {
    console.error("any catch error");
}

The client auto disconnect after 10 seconds, tho the webtransport closed promise is never reached.

Tried on 2.2.2 and 2.2.3

deno 2.2.2 (stable, release, x86_64-unknown-linux-gnu)
v8 13.4.114.9-rusty
typescript 5.7.3

[hironichu]

I tried to understand how the implementation worked to at least try to know why it happens but i cant wrap my head around it, i know its tagged as "unstable" but i was wondering if i am doing something wrong, or why hasn't it been caught during testing that if a client close the connection gracefully the server still hang until throwing a ConnectionError::timeout ?

[hironichu]

After some research , and trying some library around, part of the problem seems to be in the web-transport-proto library, and not deno's implementation.

However not being able to catch the timeout is a bug.

kixelated/web-transport-rs#66

[qihangnet]

Yes, when the client program is directly killed, the server will crash due to the error error: Uncaught (in promise) Error: timed out after about 5 seconds.

Can anyone fix it?