fix: race that causes LocalParticipant to show up as RemoteParticipant

engine.go

@@ -83,6 +83,7 @@ type RTCEngine struct {
 	OnResuming              func()
 	OnResumed               func()
 	OnTranscription         func(*livekit.Transcription)
+	OnSignalClientConnected func(*livekit.JoinResponse)
 
 	// callbacks to get data
 	CbGetLocalParticipantSID func() string
@@ -160,6 +161,10 @@ func (e *RTCEngine) JoinContext(ctx context.Context, url string, token string, p
 		return nil, err
 	}
 
+	if e.OnSignalClientConnected != nil {
+		e.OnSignalClientConnected(res)
+	}
+
 	e.client.Start()
 
 	// send offer

regionurlprovider.go

@@ -78,14 +78,19 @@ func (r *regionURLProvider) RefreshRegionSettings(cloudHostname, token string) e
 		return errors.New("refreshRegionSettings failed to decode region settings: " + err.Error())
 	}
 
-	r.mutex.Lock()
-	r.hostnameSettingsCache[cloudHostname] = &hostnameSettingsCacheItem{
+	item := &hostnameSettingsCacheItem{
 		regionSettings:    regions,
 		updatedAt:         time.Now(),
 		regionURLAttempts: map[string]int{},
 	}
+	r.mutex.Lock()
+	r.hostnameSettingsCache[cloudHostname] = item
 	r.mutex.Unlock()
 
+	if len(item.regionSettings.Regions) == 0 {
+		logger.Warnw("no regions returned", nil, "cloudHostname", cloudHostname)
+	}
+
 	return nil
 }
 

room.go

@@ -189,6 +189,7 @@
 	r.LocalParticipant = newLocalParticipant(engine, r.callback)
 
 	// callbacks from engine
+	engine.OnSignalClientConnected = r.handleSignalClientConnected
 	engine.OnMediaTrack = r.handleMediaTrack
 	engine.OnDisconnected = r.handleDisconnect
 	engine.OnParticipantUpdate = r.handleParticipantUpdate
@@ -328,6 +329,7 @@
 					d := time.Duration(1<<min(tries, 6)) * time.Second // max 64 seconds
 					logger.Errorw("failed to join room", err,
 						"retrying in", d,
+						"url", bestURL,
 					)
 					time.Sleep(d)
 					continue
@@ -338,32 +340,12 @@
 
 	if joinRes == nil {
 		var err error
 		joinRes, err = r.engine.JoinContext(ctx, url, token, params)
 		if err != nil {
 			return err
 		}
 	}
 
-	r.lock.Lock()
-	r.name = joinRes.Room.Name
-	r.metadata = joinRes.Room.Metadata
-	r.serverInfo = joinRes.ServerInfo
-	r.connectionState = ConnectionStateConnected
-	r.sifTrailer = make([]byte, len(joinRes.SifTrailer))
-	copy(r.sifTrailer, joinRes.SifTrailer)
-	r.lock.Unlock()
-
-	r.setSid(joinRes.Room.Sid, false)
-
-	r.LocalParticipant.updateInfo(joinRes.Participant)
-	r.LocalParticipant.updateSubscriptionPermission()
-
-	for _, pi := range joinRes.OtherParticipants {
-		rp := r.addRemoteParticipant(pi, true)
-		r.clearParticipantDefers(livekit.ParticipantID(pi.Sid), pi)
-		r.runParticipantDefers(livekit.ParticipantID(pi.Sid), rp)
-	}
-
 	return nil
 }
 
@@ -552,6 +534,28 @@
 	r.runParticipantDefers(livekit.ParticipantID(participantID), rp)
 }
 
+func (r *Room) handleSignalClientConnected(joinRes *livekit.JoinResponse) {
+	r.lock.Lock()
+	r.name = joinRes.Room.Name
+	r.metadata = joinRes.Room.Metadata
+	r.serverInfo = joinRes.ServerInfo
+	r.connectionState = ConnectionStateConnected
+	r.sifTrailer = make([]byte, len(joinRes.SifTrailer))
+	copy(r.sifTrailer, joinRes.SifTrailer)
+	r.lock.Unlock()
+
+	r.setSid(joinRes.Room.Sid, false)
+
+	r.LocalParticipant.updateInfo(joinRes.Participant)
+	r.LocalParticipant.updateSubscriptionPermission()
+
+	for _, pi := range joinRes.OtherParticipants {
+		r.addRemoteParticipant(pi, true)
+		r.clearParticipantDefers(livekit.ParticipantID(pi.Sid), pi)
+		// no need to run participant defers here, since we are connected for the first time
+	}
+}
+
 func (r *Room) handleDisconnect(reason DisconnectionReason) {
 	r.callback.OnDisconnected()
 	r.callback.OnDisconnectedWithReason(reason)