fix: various locks in the signaler

pkg/signaler/signaler.go

@@ -130,6 +130,7 @@ func (s *Server) CreateAuthToken(ctx context.Context, request *connect.Request[p
 			return nil, fmt.Errorf("error creating UUID: %v", err)
 		}
 		id = myUUID.String()
+		s.mu.Unlock()
 	}
 
 	token := &internalpb.AuthToken{
@@ -169,7 +170,6 @@ func (s *Server) ListCameras(ctx context.Context, request *connect.Request[pb.Li
 // Optionally, wait_for_update can be set to prevent returning until the Camera has seen the
 // session request, populated candidates, and returned a session offer.
 func (s *Server) CreateSession(ctx context.Context, request *connect.Request[pb.CreateSessionRequest]) (*connect.Response[pb.Session], error) {
-
 	log.Printf("Creating session")
 	defer log.Printf("Done session")
 	thisSession := request.Msg.Session
@@ -224,14 +224,14 @@ func (s *Server) PopSession(ctx context.Context, request *connect.Request[pb.Pop
 	s.mu.Unlock()
 
 	var sess *session
-	tick := time.NewTicker(time.Second * 30)
+	tick := time.NewTicker(time.Second * 20)
 	defer tick.Stop()
 	select {
 	case sess = <-ch:
 		// OK
 	case <-tick.C:
 		// have them retry
-		return nil, connect.NewError(connect.CodeDeadlineExceeded, fmt.Errorf("try again"))
+		return connect.NewResponse(&pb.Session{}), nil
 	}
 
 	if sess == nil {
@@ -253,17 +253,19 @@ func (s *Server) CreateIceMessage(ctx context.Context, request *connect.Request[
 	req := request.Msg
 
 	s.mu.Lock()
-	defer s.mu.Unlock()
 
 	session, ok := s.sessionsById[req.GetSessionIdentifier().GetId()]
 	if !ok {
+		s.mu.Unlock()
 		return nil, status.Errorf(codes.NotFound, "unknown session")
 	}
 
 	if _, ok := s.camerasByHome[authToken.Home]; !ok {
+		s.mu.Unlock()
 		return nil, status.Errorf(codes.NotFound, "home %q not found", authToken.Home)
 	}
 	_, isCamera := s.camerasByHome[authToken.Home][authToken.Uid]
+	s.mu.Unlock()
 
 	session.createTime = time.Now()
 	msg := req.GetIceMessage()