livekit/client-sdk-js

Prevent PCTransportManager.subscriber from reusing previous remote-track/transceiver?

patstar123 opened this issue · 3 comments

patstar123 commented

Describe the bug

issue description

  1. Everything works fine on Chrome browser and native Android WebView.
  2. But encountered oddities with Tencent X5 WebView on android:
    • Client A publishes audio, and client B subscribes the audio track. When A exits the room or stops publishing the audio track, B successfully unsubscribes from A's audio.
    • However, in Tencent's X5 WebView, additional events occur: B's MediaStreamTrack (RemoteTrack) triggers the onended callback, i.e., track.readyState is set to ended.
    • Therefore, when A rejoins the room and publishes audio again, B attempts to subscribe to that track.
    • Due to PCTransportManager.subscriber reusing the previous MediaStreamTrack, which has already ended, the subscription fails, resulting in the error message: "unable to subscribe because MediaStreamTrack is ended. Do not call MediaStreamTrack.stop()."

my request

Regarding this strange phenomenon, I have come up with two solutions:

  1. Figure out why onended is triggered on Tencent's X5 WebView and prevent it from happening again.
  2. Prevent PCTransportManager.subscriber from reusing the previous MediaStreamTrack.
    For solution 1, I have tried for a long time but without any progress. X5 is like a black box to me and i am unable to use the native WebView to replace the X5 WebView with some reasons.

So, I can only seek solution 2.

Reproduction

RT

Logs

No response

System Info

client-sdk-js: 1.15.2
x5: 46279, 20231225193004
x5 sdk: 44286

Severity

annoyance

Additional Information

No response

davidzhao commented

@AllenTu21CN, nice digging here.

It's disappointing to hear that X5 WebView isn't implementing the spec correctly.

Path 2 is an option, you can add some code to disable transceiver re-use for that particular device. It'll need to be added to the clientconfiguration package, and used in Participant.SupportsTransceiverReuse.

Do you want to open a PR with the above changes?

  • 👍2
patstar123 commented

@davidzhao
Thanks for your response. I will try to modify the code locally and test it. Once validated, I'll initiate a PR.

AnnaGromova-FD commented

Hello. We have a very similar problem with turning on the camera after re-entering room.
My technology: React + Electron.js.
After a participant leaves the room with the camera on and returns back to the room, the other participants can no longer see his video.
issue description:

  1. 2 participants enter the room, turn on their cameras. Both participants get all the information they need about the video tracks.
  2. One participant leaves the room and re-enters the same room a short time later. Turns on the camera. The second participant gets the error could not find published track {participantSid: 'PA_STthhL3q452h', participantId: '01HCEQA5ZR2MVYTY0G5Q5QYMDVXD', trackSid: 'TR_VCK2ZbmiJiiMM3'}.
    I was able to track that the trackSid value is not updated in this case. LiveKit is trying to retrieve publication by trackSid from a past room login.
    Further in the RemoteTrackPublication object the new track data appears, trackSid, trekInfo data is populated, but the track object is still undefined. As a result remote participants see a black screen.
    So, how can I get an updated track information?
  • 😕1