RTCDataChannel not properly closed

[Marcel-G]

Problem

When RTCDataChannel: close() method on a JS client (Chrome for example) the data channel hangs in closing state and never transitions to closed.
This causes a memory leak and eventually more data channels cannot be created with the following error:

Uncaught (in promise) DOMException: Failed to execute 'createDataChannel' on 'RTCPeerConnection': RTCDataChannel creation failed

Reproduction

Checkout this branch: https://github.com/Marcel-G/str0m/tree/example/close-data-channel
Run cargo run --example http-post
Click Connect, and Run
Observe data channels not entering the closed state

Possible cause

I suspect the same issue as other libraries:

• Fix Chrome datachannel stuck at closing pion/sctp#238
• RTCDataChannel not properly closed webrtc-rs/webrtc#468

Chrome is waiting for a outgoingResetRequest before considering the channel closed.

[algesten]

@Marcel-G Thanks for reporting this!

With your repro, I have made a potential fix linked above.

The main problem I see with the fix is that it doesn't close straight away. At the points this is detected in the code, it's hard to schedule an immediate write, so the response close waits for the normal RTO, which is 3000ms. Hence I had to up your test cases to like 4000ms wait.

Maybe there's some way to make this faster.

[algesten]

This is sorted in b2c5392

Thanks!