Livekit sends ParticipantLeft webhook event without ParticipantJoined webhook event if RTC connection wasn't successfull

[blombosi]

Describe the bug
If there was some error in the RTCConnection and the participant couldn't join to the session livekit still sends ParticipantLeft but didn't send ParticipantJoined webhook event.

I tried to debug the issue and found these:

livekit/pkg/rtc/room.go

Line 264 in 1019faa

r.telemetry.ParticipantActive(context.Background(), r.ToProto(), p.ToProto(), &livekit.AnalyticsClientMeta{

ParticipantJoined webhook event will be sent only if the participant state will be changed to ACTIVE, but ParticipantLeft webhook event will be sent even when the state will be changed to DISCONNECTED.
https://github.com/livekit/protocol/blob/main/livekit/livekit_models.pb.go#L345
So if the ICE connection won't be established the state will change in the following order: JOINING -> JOINED -> DISCONNECTED and joined event won't be sent but left will be.

Server

• Version: 1.2.5
• Environment: local dev, EKS

Expected behavior
I expect to always have a Join webhook event before a Left.

[jibon57]

I'm experiencing same issue too. This typically occurs when a user has a poor connection. When a person joins plugNmeet, we increase the count, and when they leave, we decrease it, but because of this issue, the total number count turned negative sometime :-D

[davidzhao]

Good point.. if it hasn't successfully joined, it makes sense that it shouldn't send a LEAVE event either.