Fix delete attributes cluster notification

application/src/main/java/org/thingsboard/server/service/subscription/DefaultSubscriptionManagerService.java

@@ -222,7 +222,7 @@ public class DefaultSubscriptionManagerService extends TbApplicationEventListene
                         }
                     }
                     return subscriptionUpdate;
-                });
+                }, true);
         if (entityId.getEntityType() == EntityType.DEVICE) {
             updateDeviceInactivityTimeout(tenantId, entityId, ts);
         }
@@ -256,7 +256,7 @@ public class DefaultSubscriptionManagerService extends TbApplicationEventListene
                         }
                     }
                     return subscriptionUpdate;
-                });
+                }, true);
         if (entityId.getEntityType() == EntityType.DEVICE) {
             if (TbAttributeSubscriptionScope.SERVER_SCOPE.name().equalsIgnoreCase(scope)) {
                 updateDeviceInactivityTimeout(tenantId, entityId, attributes);
@@ -333,14 +333,15 @@ public class DefaultSubscriptionManagerService extends TbApplicationEventListene
                         }
                     }
                     return subscriptionUpdate;
-                });
+                }, false);
         callback.onSuccess();
     }
 
     private <T extends TbSubscription> void onLocalTelemetrySubUpdate(EntityId entityId,
                                                                       Function<TbSubscription, T> castFunction,
                                                                       Predicate<T> filterFunction,
-                                                                      Function<T, List<TsKvEntry>> processFunction) {
+                                                                      Function<T, List<TsKvEntry>> processFunction,
+                                                                      boolean ignoreEmptyUpdates) {
         Set<TbSubscription> entitySubscriptions = subscriptionsByEntityId.get(entityId);
         if (entitySubscriptions != null) {
             entitySubscriptions.stream().map(castFunction).filter(Objects::nonNull).filter(filterFunction).forEach(s -> {
@@ -351,7 +352,7 @@ public class DefaultSubscriptionManagerService extends TbApplicationEventListene
                         localSubscriptionService.onSubscriptionUpdate(s.getSessionId(), update, TbCallback.EMPTY);
                     } else {
                         TopicPartitionInfo tpi = partitionService.getNotificationsTopic(ServiceType.TB_CORE, s.getServiceId());
-                        toCoreNotificationsProducer.send(tpi, toProto(s, subscriptionUpdate), null);
+                        toCoreNotificationsProducer.send(tpi, toProto(s, subscriptionUpdate, ignoreEmptyUpdates), null);
                     }
                 }
             });
@@ -467,6 +468,10 @@ public class DefaultSubscriptionManagerService extends TbApplicationEventListene
     }
 
     private TbProtoQueueMsg<ToCoreNotificationMsg> toProto(TbSubscription subscription, List<TsKvEntry> updates) {
+        return toProto(subscription, updates, true);
+    }
+
+    private TbProtoQueueMsg<ToCoreNotificationMsg> toProto(TbSubscription subscription, List<TsKvEntry> updates, boolean ignoreEmptyUpdates) {
         TbSubscriptionUpdateProto.Builder builder = TbSubscriptionUpdateProto.newBuilder();
 
         builder.setSessionId(subscription.getSessionId());
@@ -494,7 +499,7 @@ public class DefaultSubscriptionManagerService extends TbApplicationEventListene
                     dataBuilder.addValue(strVal);
                 }
             }
-            if (hasData) {
+            if (!ignoreEmptyUpdates || hasData) {
                 builder.addData(dataBuilder.build());
             }
         });