Send error response when update metadata fails. (#2849)

Keeping it simple for the first implementation.
- Send error response only if request_id != 0
- Two kinds of errors notified
  o does not have permissions - NOT_ALLOWED
  o attributes exceeds size limits -  INVALID_ARGUMENT

pkg/rtc/participant_signal.go

@@ -197,6 +197,18 @@ func (p *ParticipantImpl) SendRefreshToken(token string) error {
 	})
 }
 
+func (p *ParticipantImpl) SendErrorResponse(errorResponse *livekit.ErrorResponse) error {
+	if errorResponse.RequestId == 0 {
+		return nil
+	}
+
+	return p.writeMessage(&livekit.SignalResponse{
+		Message: &livekit.SignalResponse_ErrorResponse{
+			ErrorResponse: errorResponse,
+		},
+	})
+}
+
 func (p *ParticipantImpl) HandleReconnectAndSendResponse(reconnectReason livekit.ReconnectReason, reconnectResponse *livekit.ReconnectResponse) error {
 	p.TransportManager.HandleClientReconnect(reconnectReason)
 

pkg/rtc/signalhandler.go

@@ -92,6 +92,7 @@ func HandleParticipantSignal(room types.Room, participant types.LocalParticipant
 		}
 
 	case *livekit.SignalRequest_UpdateMetadata:
+		var errorResponse *livekit.ErrorResponse
 		if participant.ClaimGrants().Video.GetCanUpdateOwnMetadata() {
 			err := room.UpdateParticipantMetadata(
 				participant,
@@ -101,7 +102,25 @@ func HandleParticipantSignal(room types.Room, participant types.LocalParticipant
 			)
 			if err != nil {
 				pLogger.Warnw("could not update metadata", err)
+
+				switch err {
+				case ErrAttributeExceedsLimits:
+					errorResponse = &livekit.ErrorResponse{
+						Reason:  livekit.ErrorResponse_INVALID_ARGUMENT,
+						Message: "exceeds attributes size limit",
+					}
+				}
+
 			}
+		} else {
+			errorResponse = &livekit.ErrorResponse{
+				Reason:  livekit.ErrorResponse_NOT_ALLOWED,
+				Message: "does not have permission to update own metadata",
+			}
+		}
+		if errorResponse != nil {
+			errorResponse.RequestId = msg.UpdateMetadata.RequestId
+			participant.SendErrorResponse(errorResponse)
 		}
 
 	case *livekit.SignalRequest_UpdateAudioTrack:

pkg/rtc/types/interfaces.go

@@ -379,6 +379,7 @@ type LocalParticipant interface {
 	SendConnectionQualityUpdate(update *livekit.ConnectionQualityUpdate) error
 	SubscriptionPermissionUpdate(publisherID livekit.ParticipantID, trackID livekit.TrackID, allowed bool)
 	SendRefreshToken(token string) error
+	SendErrorResponse(errorResponse *livekit.ErrorResponse) error
 	HandleReconnectAndSendResponse(reconnectReason livekit.ReconnectReason, reconnectResponse *livekit.ReconnectResponse) error
 	IssueFullReconnect(reason ParticipantCloseReason)
 

pkg/rtc/types/typesfakes/fake_local_participant.go

@@ -677,6 +677,17 @@ type FakeLocalParticipant struct {
 	sendDataPacketReturnsOnCall map[int]struct {
 		result1 error
 	}
+	SendErrorResponseStub        func(*livekit.ErrorResponse) error
+	sendErrorResponseMutex       sync.RWMutex
+	sendErrorResponseArgsForCall []struct {
+		arg1 *livekit.ErrorResponse
+	}
+	sendErrorResponseReturns struct {
+		result1 error
+	}
+	sendErrorResponseReturnsOnCall map[int]struct {
+		result1 error
+	}
 	SendJoinResponseStub        func(*livekit.JoinResponse) error
 	sendJoinResponseMutex       sync.RWMutex
 	sendJoinResponseArgsForCall []struct {
@@ -4576,6 +4587,67 @@ func (fake *FakeLocalParticipant) SendDataPacketReturnsOnCall(i int, result1 err
 	}{result1}
 }
 
+func (fake *FakeLocalParticipant) SendErrorResponse(arg1 *livekit.ErrorResponse) error {
+	fake.sendErrorResponseMutex.Lock()
+	ret, specificReturn := fake.sendErrorResponseReturnsOnCall[len(fake.sendErrorResponseArgsForCall)]
+	fake.sendErrorResponseArgsForCall = append(fake.sendErrorResponseArgsForCall, struct {
+		arg1 *livekit.ErrorResponse
+	}{arg1})
+	stub := fake.SendErrorResponseStub
+	fakeReturns := fake.sendErrorResponseReturns
+	fake.recordInvocation("SendErrorResponse", []interface{}{arg1})
+	fake.sendErrorResponseMutex.Unlock()
+	if stub != nil {
+		return stub(arg1)
+	}
+	if specificReturn {
+		return ret.result1
+	}
+	return fakeReturns.result1
+}
+
+func (fake *FakeLocalParticipant) SendErrorResponseCallCount() int {
+	fake.sendErrorResponseMutex.RLock()
+	defer fake.sendErrorResponseMutex.RUnlock()
+	return len(fake.sendErrorResponseArgsForCall)
+}
+
+func (fake *FakeLocalParticipant) SendErrorResponseCalls(stub func(*livekit.ErrorResponse) error) {
+	fake.sendErrorResponseMutex.Lock()
+	defer fake.sendErrorResponseMutex.Unlock()
+	fake.SendErrorResponseStub = stub
+}
+
+func (fake *FakeLocalParticipant) SendErrorResponseArgsForCall(i int) *livekit.ErrorResponse {
+	fake.sendErrorResponseMutex.RLock()
+	defer fake.sendErrorResponseMutex.RUnlock()
+	argsForCall := fake.sendErrorResponseArgsForCall[i]
+	return argsForCall.arg1
+}
+
+func (fake *FakeLocalParticipant) SendErrorResponseReturns(result1 error) {
+	fake.sendErrorResponseMutex.Lock()
+	defer fake.sendErrorResponseMutex.Unlock()
+	fake.SendErrorResponseStub = nil
+	fake.sendErrorResponseReturns = struct {
+		result1 error
+	}{result1}
+}
+
+func (fake *FakeLocalParticipant) SendErrorResponseReturnsOnCall(i int, result1 error) {
+	fake.sendErrorResponseMutex.Lock()
+	defer fake.sendErrorResponseMutex.Unlock()
+	fake.SendErrorResponseStub = nil
+	if fake.sendErrorResponseReturnsOnCall == nil {
+		fake.sendErrorResponseReturnsOnCall = make(map[int]struct {
+			result1 error
+		})
+	}
+	fake.sendErrorResponseReturnsOnCall[i] = struct {
+		result1 error
+	}{result1}
+}
+
 func (fake *FakeLocalParticipant) SendJoinResponse(arg1 *livekit.JoinResponse) error {
 	fake.sendJoinResponseMutex.Lock()
 	ret, specificReturn := fake.sendJoinResponseReturnsOnCall[len(fake.sendJoinResponseArgsForCall)]
@@ -6633,6 +6705,8 @@ func (fake *FakeLocalParticipant) Invocations() map[string][][]interface{} {
 	defer fake.sendConnectionQualityUpdateMutex.RUnlock()
 	fake.sendDataPacketMutex.RLock()
 	defer fake.sendDataPacketMutex.RUnlock()
+	fake.sendErrorResponseMutex.RLock()
+	defer fake.sendErrorResponseMutex.RUnlock()
 	fake.sendJoinResponseMutex.RLock()
 	defer fake.sendJoinResponseMutex.RUnlock()
 	fake.sendParticipantUpdateMutex.RLock()