unify resume/restart in single/multi node mode (#946)

pkg/routing/localrouter.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/livekit/protocol/livekit"
 	"github.com/livekit/protocol/logger"
+	"github.com/livekit/protocol/utils"
 )
 
 // aggregated channel for all participants
@@ -87,8 +88,11 @@ func (r *LocalRouter) StartParticipantSignal(ctx context.Context, roomName livek
 		return
 	}
 
+	// create a new connection id
+	connectionID = livekit.ConnectionID(utils.NewGuid("CO_"))
 	// index channels by roomName | identity
 	key := participantKey(roomName, pi.Identity)
+	key = key + "|" + livekit.ParticipantKey(connectionID)
 
 	// close older channels if one already exists
 	reqChan := r.getMessageChannel(r.requestChannels, string(key))
@@ -121,7 +125,7 @@ func (r *LocalRouter) StartParticipantSignal(ctx context.Context, roomName livek
 			)
 		}
 	}()
-	return livekit.ConnectionID(pi.Identity), reqChan, resChan, nil
+	return connectionID, reqChan, resChan, nil
 }
 
 func (r *LocalRouter) WriteParticipantRTC(_ context.Context, roomName livekit.RoomName, identity livekit.ParticipantIdentity, msg *livekit.RTCNodeMessage) error {

pkg/routing/redisrouter.go

@@ -230,16 +230,14 @@ func (r *RedisRouter) startParticipantRTC(ss *livekit.StartSession, participantK
 		return ErrHandlerNotDefined
 	}
 
-	if !ss.Reconnect {
-		// when it's not reconnecting, we do not want to re-use the same response sink
-		// the previous rtc worker thread is still consuming off of it.
-		// we'll want to sever the connection and switch to the new one
-		r.lock.RLock()
-		requestChan, ok := r.requestChannels[string(participantKey)]
-		r.lock.RUnlock()
-		if ok {
-			requestChan.Close()
-		}
+	// we do not want to re-use the same response sink
+	// the previous rtc worker thread is still consuming off of it.
+	// we'll want to sever the connection and switch to the new one
+	r.lock.RLock()
+	requestChan, ok := r.requestChannels[string(participantKey)]
+	r.lock.RUnlock()
+	if ok {
+		requestChan.Close()
 	}
 
 	pi, err := ParticipantInitFromStartSession(ss, r.currentNode.Region)