refactored due to comments

application/src/main/java/org/thingsboard/server/actors/ruleChain/RuleNodeActorMessageProcessor.java

@@ -60,7 +60,7 @@ public class RuleNodeActorMessageProcessor extends ComponentMsgProcessor<RuleNod
 
     @Override
     public void start(TbActorCtx context) throws Exception {
-        if (isMySingletonNode()) {
+        if (isMyNodePartition()) {
             tbNode = initComponent(ruleNode);
             if (tbNode != null) {
                 state = ComponentLifecycleState.ACTIVE;
@@ -70,7 +70,7 @@ public class RuleNodeActorMessageProcessor extends ComponentMsgProcessor<RuleNod
 
     @Override
     public void onUpdate(TbActorCtx context) throws Exception {
-        if (isMySingletonNode()) {
+        if (isMyNodePartition()) {
             RuleNode newRuleNode = systemContext.getRuleChainService().findRuleNodeById(tenantId, entityId);
             this.info = new RuleNodeInfo(entityId, ruleChainName, newRuleNode != null ? newRuleNode.getName() : "Unknown");
             boolean restartRequired = state != ComponentLifecycleState.ACTIVE ||
@@ -104,13 +104,13 @@ public class RuleNodeActorMessageProcessor extends ComponentMsgProcessor<RuleNod
     @Override
     public void onPartitionChangeMsg(PartitionChangeMsg msg) throws Exception {
         if (tbNode != null) {
-            if (!isMySingletonNode()) {
+            if (!isMyNodePartition()) {
                 stop(null);
                 tbNode = null;
             } else {
                 tbNode.onPartitionChangeMsg(defaultCtx, msg);
             }
-        } else if (isMySingletonNode()) {
+        } else if (isMyNodePartition()) {
             start(null);
         }
     }
@@ -136,8 +136,8 @@ public class RuleNodeActorMessageProcessor extends ComponentMsgProcessor<RuleNod
     }
 
     void onRuleChainToRuleNodeMsg(RuleChainToRuleNodeMsg msg) throws Exception {
-        if (!isMySingletonNode()) {
-            putToQueue(msg.getMsg());
+        if (!isMyNodePartition()) {
+            putToNodePartition(msg.getMsg());
         } else {
             msg.getMsg().getCallback().onProcessingStart(info);
             checkComponentStateActive(msg.getMsg());
@@ -180,15 +180,16 @@ public class RuleNodeActorMessageProcessor extends ComponentMsgProcessor<RuleNod
         return new RuleNodeException("Rule Node is not active! Failed to initialize.", ruleChainName, ruleNode);
     }
 
-    private boolean isMySingletonNode() {
+    private boolean isMyNodePartition() {
         return !ruleNode.isSingletonMode()
                 || systemContext.getDiscoveryService().isMonolith()
                 || defaultCtx.isLocalEntity(ruleNode.getId());
     }
 
-    private void putToQueue(TbMsg source) {
+    //Message will return after processing. See RuleChainActorMessageProcessor.pushToTarget.
+    private void putToNodePartition(TbMsg source) {
         TbMsg tbMsg = TbMsg.newMsg(source, source.getQueueName(), source.getRuleChainId(), entityId);
-        TopicPartitionInfo tpi = systemContext.resolve(ServiceType.TB_RULE_ENGINE, tbMsg.getQueueName(), tenantId, entityId);
+        TopicPartitionInfo tpi = systemContext.resolve(ServiceType.TB_RULE_ENGINE, tbMsg.getQueueName(), tenantId, ruleNode.getId());
         TransportProtos.ToRuleEngineMsg toQueueMsg = TransportProtos.ToRuleEngineMsg.newBuilder()
                 .setTenantIdMSB(tenantId.getId().getMostSignificantBits())
                 .setTenantIdLSB(tenantId.getId().getLeastSignificantBits())

application/src/test/java/org/thingsboard/server/service/RuleChainDataValidatorTest.java

@@ -1,66 +0,0 @@
-/**
- * Copyright © 2016-2023 The Thingsboard Authors
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.thingsboard.server.service;
-
-import org.junit.Test;
-import org.junit.jupiter.api.Assertions;
-import org.thingsboard.common.util.JacksonUtil;
-import org.thingsboard.server.common.data.rule.RuleNode;
-import org.thingsboard.server.dao.exception.DataValidationException;
-import org.thingsboard.server.dao.service.validator.RuleChainDataValidator;
-
-public class RuleChainDataValidatorTest {
-
-    @Test
-    public void testSingletonSupport() {
-        String node = "org.thingsboard.rule.engine.mqtt.TbMqttNode";
-        RuleNode ruleNode = createRuleNode(node, false);
-        RuleChainDataValidator.validateRuleNode(ruleNode);
-        ruleNode.setSingletonMode(true);
-        RuleChainDataValidator.validateRuleNode(ruleNode);
-    }
-
-    @Test
-    public void testSingletonNotSupport() {
-        String node = "org.thingsboard.rule.engine.flow.TbAckNode";
-        RuleNode ruleNode = createRuleNode(node, false);
-        RuleChainDataValidator.validateRuleNode(ruleNode);
-        ruleNode.setSingletonMode(true);
-        Assertions.assertThrows(DataValidationException.class,
-                () -> RuleChainDataValidator.validateRuleNode(ruleNode),
-                String.format("Singleton mode not supported for [%s].", ruleNode.getType()));
-    }
-
-    @Test
-    public void testSingletonOnly() {
-        String node = "org.thingsboard.rule.engine.mqtt.azure.TbAzureIotHubNode";
-        RuleNode ruleNode = createRuleNode(node, true);
-        RuleChainDataValidator.validateRuleNode(ruleNode);
-        ruleNode.setSingletonMode(false);
-        Assertions.assertThrows(DataValidationException.class,
-                () -> RuleChainDataValidator.validateRuleNode(ruleNode),
-                String.format("Supported only singleton mode for [%s].", ruleNode.getType()));
-    }
-
-    private RuleNode createRuleNode(String type, boolean singletonMode) {
-        RuleNode ruleNode = new RuleNode();
-        ruleNode.setName("test node");
-        ruleNode.setType(type);
-        ruleNode.setSingletonMode(singletonMode);
-        ruleNode.setConfiguration(JacksonUtil.newObjectNode());
-        return ruleNode;
-    }
-}

dao/src/main/java/org/thingsboard/server/dao/rule/BaseRuleChainService.java

@@ -38,6 +38,7 @@ import org.thingsboard.server.common.data.id.RuleNodeId;
 import org.thingsboard.server.common.data.id.TenantId;
 import org.thingsboard.server.common.data.page.PageData;
 import org.thingsboard.server.common.data.page.PageLink;
+import org.thingsboard.server.common.data.plugin.ComponentClusteringMode;
 import org.thingsboard.server.common.data.relation.EntityRelation;
 import org.thingsboard.server.common.data.relation.RelationTypeGroup;
 import org.thingsboard.server.common.data.rule.NodeConnectionInfo;
@@ -50,6 +51,7 @@ import org.thingsboard.server.common.data.rule.RuleChainType;
 import org.thingsboard.server.common.data.rule.RuleChainUpdateResult;
 import org.thingsboard.server.common.data.rule.RuleNode;
 import org.thingsboard.server.common.data.rule.RuleNodeUpdateResult;
+import org.thingsboard.server.common.data.util.ReflectionUtils;
 import org.thingsboard.server.dao.entity.AbstractEntityService;
 import org.thingsboard.server.dao.exception.DataValidationException;
 import org.thingsboard.server.dao.service.DataValidator;
@@ -146,6 +148,7 @@ public class BaseRuleChainService extends AbstractEntityService implements RuleC
         Map<RuleNodeId, Integer> ruleNodeIndexMap = new HashMap<>();
         if (nodes != null) {
             for (RuleNode node : nodes) {
+                setSingletonMode(node);
                 if (node.getId() != null) {
                     ruleNodeIndexMap.put(node.getId(), nodes.indexOf(node));
                 } else {
@@ -769,4 +772,30 @@ public class BaseRuleChainService extends AbstractEntityService implements RuleC
                 }
             };
 
+    private void setSingletonMode(RuleNode ruleNode) {
+        boolean singletonMode;
+        try {
+            ComponentClusteringMode nodeConfigType = ReflectionUtils.getAnnotationProperty(ruleNode.getType(),
+                    "org.thingsboard.rule.engine.api.RuleNode", "clusteringMode");
+
+            switch (nodeConfigType) {
+                case ENABLED:
+                    singletonMode = false;
+                    break;
+                case SINGLETON:
+                    singletonMode = true;
+                    break;
+                case USER_PREFERENCE:
+                default:
+                    singletonMode = ruleNode.isSingletonMode();
+                    break;
+            }
+        } catch (Exception e) {
+            log.warn("Failed to get clustering mode: {}", ExceptionUtils.getRootCauseMessage(e));
+            singletonMode = false;
+        }
+
+        ruleNode.setSingletonMode(singletonMode);
+    }
+
 }

dao/src/main/java/org/thingsboard/server/dao/service/validator/RuleChainDataValidator.java

@@ -25,7 +25,6 @@ import org.thingsboard.common.util.JacksonUtil;
 import org.thingsboard.server.common.data.EntityType;
 import org.thingsboard.server.common.data.StringUtils;
 import org.thingsboard.server.common.data.id.TenantId;
-import org.thingsboard.server.common.data.plugin.ComponentClusteringMode;
 import org.thingsboard.server.common.data.rule.NodeConnectionInfo;
 import org.thingsboard.server.common.data.rule.RuleChain;
 import org.thingsboard.server.common.data.rule.RuleChainMetaData;
@@ -113,22 +112,6 @@ public class RuleChainDataValidator extends DataValidator<RuleChain> {
             return;
         }
         ConstraintValidator.validateFields(nodeConfig, errorPrefix);
-
-        ComponentClusteringMode nodeConfigType = null;
-        try {
-            nodeConfigType = ReflectionUtils.getAnnotationProperty(ruleNode.getType(),
-                    "org.thingsboard.rule.engine.api.RuleNode", "clusteringMode");
-        } catch (Exception e) {
-            log.warn("Failed to validate singleton mode: {}", ExceptionUtils.getRootCauseMessage(e));
-            return;
-        }
-        if (ComponentClusteringMode.ENABLED.equals(nodeConfigType) && ruleNode.isSingletonMode()) {
-            throw new DataValidationException(String.format("Singleton mode not supported for [%s].", ruleNode.getType()));
-        }
-
-        if (ComponentClusteringMode.SINGLETON.equals(nodeConfigType) && !ruleNode.isSingletonMode()) {
-            throw new DataValidationException(String.format("Supported only singleton mode for [%s].", ruleNode.getType()));
-        }
     }
 
     private static void validateCircles(List<NodeConnectionInfo> connectionInfos) {