AI rule node: add dedicated thread pool for AI requests

application/src/main/java/org/thingsboard/server/actors/ActorSystemContext.java

@@ -30,6 +30,7 @@ import org.springframework.context.annotation.Lazy;
 import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.stereotype.Component;
 import org.thingsboard.common.util.JacksonUtil;
+import org.thingsboard.rule.engine.api.AiRequestsExecutor;
 import org.thingsboard.rule.engine.api.DeviceStateManager;
 import org.thingsboard.rule.engine.api.MailService;
 import org.thingsboard.rule.engine.api.MqttClientSettings;
@@ -319,6 +320,10 @@ public class ActorSystemContext {
     @Getter
     private AiSettingsService aiSettingsService;
 
+    @Autowired
+    @Getter
+    private AiRequestsExecutor aiRequestsExecutor;
+
     @Autowired
     @Getter
     private EntityViewService entityViewService;

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

@@ -23,6 +23,7 @@ import org.bouncycastle.util.Arrays;
 import org.thingsboard.common.util.DebugModeUtil;
 import org.thingsboard.common.util.JacksonUtil;
 import org.thingsboard.common.util.ListeningExecutor;
+import org.thingsboard.rule.engine.api.AiRequestsExecutor;
 import org.thingsboard.rule.engine.api.DeviceStateManager;
 import org.thingsboard.rule.engine.api.MailService;
 import org.thingsboard.rule.engine.api.MqttClientSettings;
@@ -1024,6 +1025,11 @@ public class DefaultTbContext implements TbContext {
         return mainCtx.getAiSettingsService();
     }
 
+    @Override
+    public AiRequestsExecutor getAiRequestsExecutor() {
+        return mainCtx.getAiRequestsExecutor();
+    }
+
     @Override
     public MqttClientSettings getMqttClientSettings() {
         return mainCtx.getMqttClientSettings();

application/src/main/java/org/thingsboard/server/service/ai/AiRequestsExecutorProperties.java

@@ -0,0 +1,43 @@
+/**
+ * Copyright © 2016-2025 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.ai;
+
+import jakarta.validation.constraints.Min;
+import jakarta.validation.constraints.NotBlank;
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.validation.annotation.Validated;
+
+@Data
+@Validated
+@Configuration
+@ConfigurationProperties(prefix = "actors.rule.ai-requests-thread-pool")
+class AiRequestsExecutorProperties {
+
+    @NotBlank(message = "Pool name must be not blank")
+    private String poolName = "ai-requests";
+
+    @Min(value = 1, message = "Pool size must be at least 1")
+    private int poolSize = 50;
+
+    @Min(value = 1, message = "Max queue size must be at least 1")
+    private int maxQueueSize = 10000;
+
+    @Min(value = 1, message = "Termination timeout must be at least 1 second")
+    private int terminationTimeoutSeconds = 60;
+
+}

application/src/main/java/org/thingsboard/server/service/ai/DefaultAiRequestsExecutor.java

@@ -0,0 +1,63 @@
+/**
+ * Copyright © 2016-2025 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.ai;
+
+import com.google.common.util.concurrent.FluentFuture;
+import com.google.common.util.concurrent.ListeningExecutorService;
+import com.google.common.util.concurrent.MoreExecutors;
+import dev.langchain4j.model.chat.ChatModel;
+import dev.langchain4j.model.chat.request.ChatRequest;
+import dev.langchain4j.model.chat.response.ChatResponse;
+import jakarta.annotation.PostConstruct;
+import jakarta.annotation.PreDestroy;
+import lombok.RequiredArgsConstructor;
+import org.springframework.context.annotation.Lazy;
+import org.springframework.stereotype.Component;
+import org.thingsboard.common.util.ThingsBoardExecutors;
+import org.thingsboard.rule.engine.api.AiRequestsExecutor;
+
+import java.time.Duration;
+
+@Lazy
+@Component
+@RequiredArgsConstructor
+class DefaultAiRequestsExecutor implements AiRequestsExecutor {
+
+    private final AiRequestsExecutorProperties properties;
+
+    private ListeningExecutorService executorService;
+
+    @PostConstruct
+    private void init() {
+        executorService = MoreExecutors.listeningDecorator(
+                ThingsBoardExecutors.newLimitedTasksExecutor(properties.getPoolSize(), properties.getMaxQueueSize(), properties.getPoolName())
+        );
+    }
+
+    @Override
+    public FluentFuture<ChatResponse> sendChatRequestAsync(ChatModel chatModel, ChatRequest chatRequest) {
+        return FluentFuture.from(executorService.submit(() -> chatModel.chat(chatRequest)));
+    }
+
+    @PreDestroy
+    private void destroy() {
+        if (executorService != null) {
+            MoreExecutors.shutdownAndAwaitTermination(executorService, Duration.ofSeconds(properties.getTerminationTimeoutSeconds()));
+            executorService = null;
+        }
+    }
+
+}

application/src/main/resources/thingsboard.yml

@@ -463,6 +463,16 @@ actors:
     allow_system_sms_service: "${ACTORS_RULE_ALLOW_SYSTEM_SMS_SERVICE:true}"
     # Specify thread pool size for external call service
     external_call_thread_pool_size: "${ACTORS_RULE_EXTERNAL_CALL_THREAD_POOL_SIZE:50}"
+    # Configuration for the thread pool that executes HTTP calls to AI provider APIs
+    ai-requests-thread-pool:
+      # The base name for threads
+      pool-name: "${ACTORS_RULE_AI_REQUESTS_THREAD_POOL_NAME:ai-requests}"
+      # The maximum number of concurrent HTTP requests
+      pool-size: "${ACTORS_RULE_AI_REQUESTS_THREAD_POOL_SIZE:50}"
+      # The maximum queue size for pending AI requests
+      max-queue-size: "${ACTORS_RULE_AI_REQUESTS_THREAD_POOL_QUEUE_SIZE:10000}"
+      # The maximum time in seconds to wait for active tasks to complete during graceful shutdown
+      termination-timeout-seconds: "${ACTORS_RULE_AI_REQUESTS_THREAD_POOL_TERMINATION_TIMEOUT_SECONDS:60}"
     chain:
       # Errors for particular actors are persisted once per specified amount of milliseconds
       error_persist_frequency: "${ACTORS_RULE_CHAIN_ERROR_FREQUENCY:3000}"

rule-engine/rule-engine-api/src/main/java/org/thingsboard/rule/engine/api/AiRequestsExecutor.java

@@ -0,0 +1,27 @@
+/**
+ * Copyright © 2016-2025 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.rule.engine.api;
+
+import com.google.common.util.concurrent.FluentFuture;
+import dev.langchain4j.model.chat.ChatModel;
+import dev.langchain4j.model.chat.request.ChatRequest;
+import dev.langchain4j.model.chat.response.ChatResponse;
+
+public interface AiRequestsExecutor {
+
+    FluentFuture<ChatResponse> sendChatRequestAsync(ChatModel chatModel, ChatRequest chatRequest);
+
+}

rule-engine/rule-engine-api/src/main/java/org/thingsboard/rule/engine/api/TbContext.java

@@ -422,6 +422,8 @@ public interface TbContext {
 
     AiSettingsService getAiSettingsService();
 
+    AiRequestsExecutor getAiRequestsExecutor();
+
     // Configuration parameters for the MQTT client that is used in the MQTT node and Azure IoT hub node
 
     MqttClientSettings getMqttClientSettings();

rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/ai/TbAiNode.java

@@ -26,6 +26,7 @@ import dev.langchain4j.model.chat.request.ChatRequest;
 import dev.langchain4j.model.chat.request.ResponseFormat;
 import dev.langchain4j.model.chat.request.ResponseFormatType;
 import dev.langchain4j.model.chat.request.json.JsonSchema;
+import dev.langchain4j.model.chat.response.ChatResponse;
 import dev.langchain4j.model.input.PromptTemplate;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.thingsboard.common.util.JacksonUtil;
@@ -130,10 +131,11 @@ public final class TbAiNode extends TbAbstractExternalNode implements TbNode {
                 .build();
 
         configureChatModelAsync(ctx)
-                .transform(chatModel -> sendChatRequest(chatModel, chatRequest), ctx.getExternalCallExecutor())
+                .transformAsync(chatModel -> ctx.getAiRequestsExecutor().sendChatRequestAsync(chatModel, chatRequest), directExecutor())
                 .addCallback(new FutureCallback<>() {
                     @Override
-                    public void onSuccess(String response) {
+                    public void onSuccess(ChatResponse chatResponse) {
+                        String response = chatResponse.aiMessage().text();
                         if (!isValidJsonObject(response)) {
                             response = wrapInJsonObject(response);
                         }
@@ -165,10 +167,6 @@ public final class TbAiNode extends TbAbstractExternalNode implements TbNode {
         }, ctx.getDbCallbackExecutor());
     }
 
-    private String sendChatRequest(ChatModel chatModel, ChatRequest chatRequest) {
-        return chatModel.chat(chatRequest).aiMessage().text();
-    }
-
     private static boolean isValidJsonObject(String jsonString) {
         try {
             JsonNode result = JacksonUtil.toJsonNode(jsonString);