wait on local topic partition creation

weed/mq/broker/broker_grpc_sub.go

@@ -13,10 +13,17 @@ import (
 
 func (b *MessageQueueBroker) SubscribeMessage(req *mq_pb.SubscribeMessageRequest, stream mq_pb.SeaweedMessaging_SubscribeMessageServer) error {
 
+	ctx := stream.Context()
+	clientName := fmt.Sprintf("%s/%s-%s", req.GetInit().ConsumerGroup, req.GetInit().ConsumerId, req.GetInit().ClientId)
+
 	t := topic.FromPbTopic(req.GetInit().Topic)
 	partition := topic.FromPbPartition(req.GetInit().GetPartitionOffset().GetPartition())
-	localTopicPartition := b.localTopicManager.GetTopicPartition(t, partition)
-	if localTopicPartition == nil {
+
+	glog.V(0).Infof("Subscriber %s on %v %v connected", req.GetInit().ConsumerId, t, partition)
+
+	var localTopicPartition *topic.LocalPartition
+	localTopicPartition = b.localTopicManager.GetTopicPartition(t, partition)
+	for localTopicPartition == nil {
 		stream.Send(&mq_pb.SubscribeMessageResponse{
 			Message: &mq_pb.SubscribeMessageResponse_Ctrl{
 				Ctrl: &mq_pb.SubscribeMessageResponse_CtrlMessage{
@@ -24,10 +31,23 @@ func (b *MessageQueueBroker) SubscribeMessage(req *mq_pb.SubscribeMessageRequest
 				},
 			},
 		})
-		return nil
+		time.Sleep(337 * time.Millisecond)
+		// Check if the client has disconnected by monitoring the context
+		select {
+		case <-ctx.Done():
+			err := ctx.Err()
+			if err == context.Canceled {
+				// Client disconnected
+				return nil
+			}
+			glog.V(0).Infof("Subscriber %s disconnected: %v", clientName, err)
+			return nil
+		default:
+			// Continue processing the request
+		}
+		localTopicPartition = b.localTopicManager.GetTopicPartition(t, partition)
 	}
 
-	clientName := fmt.Sprintf("%s/%s-%s", req.GetInit().ConsumerGroup, req.GetInit().ConsumerId, req.GetInit().ClientId)
 	localTopicPartition.Subscribers.AddSubscriber(clientName, topic.NewLocalSubscriber())
 	glog.V(0).Infof("Subscriber %s connected on %v %v", clientName, t, partition)
 	isConnected := true
@@ -38,7 +58,6 @@ func (b *MessageQueueBroker) SubscribeMessage(req *mq_pb.SubscribeMessageRequest
 		glog.V(0).Infof("Subscriber %s on %v %v disconnected", clientName, t, partition)
 	}()
 
-	ctx := stream.Context()
 	var startPosition log_buffer.MessagePosition
 	var inMemoryOnly bool
 	if req.GetInit()!=nil && req.GetInit().GetPartitionOffset() != nil {