【功能完善】IoT: 新增 MQTT RPC 支持，包含请求和响应模型、序列化工具、MQTT 配置及客户端/服务器实现，提供示例服务和控制器接口，优化插件结构以支持 HTTP 插件的集成。

yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/mqttrpc/config/MqttConfig.java

@@ -0,0 +1,40 @@
+package cn.iocoder.yudao.module.iot.mqttrpc.config;
+
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.context.annotation.Configuration;
+
+@Data
+@Configuration
+@ConfigurationProperties(prefix = "mqtt")
+public class MqttConfig {
+    /**
+     * MQTT 代理地址    
+     */
+    private String broker;
+
+    /**
+     * MQTT 用户名
+     */
+    private String username;
+
+    /**
+     * MQTT 密码
+     */
+    private String password;
+
+    /**
+     * MQTT 客户端 ID
+     */
+    private String clientId;
+
+    /**
+     * MQTT 请求主题
+     */
+    private String requestTopic;
+
+    /**
+     * MQTT 响应主题前缀
+     */
+    private String responseTopicPrefix;
+}

yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/mqttrpc/server/RpcServer.java

@@ -0,0 +1,95 @@
+package cn.iocoder.yudao.module.iot.mqttrpc.server;
+
+import cn.hutool.core.lang.UUID;
+import cn.iocoder.yudao.module.iot.mqttrpc.common.RpcRequest;
+import cn.iocoder.yudao.module.iot.mqttrpc.common.RpcResponse;
+import cn.iocoder.yudao.module.iot.mqttrpc.common.SerializationUtils;
+import cn.iocoder.yudao.module.iot.mqttrpc.config.MqttConfig;
+import lombok.extern.slf4j.Slf4j;
+import org.eclipse.paho.client.mqttv3.*;
+import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;
+import org.springframework.stereotype.Service;
+
+import javax.annotation.PostConstruct;
+import javax.annotation.PreDestroy;
+import java.util.HashMap;
+import java.util.Map;
+
+@Service
+@Slf4j
+public class RpcServer {
+
+    private final MqttConfig mqttConfig;
+    private final MqttClient mqttClient;
+    private final Map<String, MethodInvoker> methodRegistry = new HashMap<>();
+
+    public RpcServer(MqttConfig mqttConfig) throws MqttException {
+        this.mqttConfig = mqttConfig;
+        this.mqttClient = new MqttClient(mqttConfig.getBroker(), "rpc-server-" + UUID.randomUUID(), new MemoryPersistence());
+        MqttConnectOptions options = new MqttConnectOptions();
+        options.setAutomaticReconnect(true);
+        options.setCleanSession(true);
+        options.setUserName(mqttConfig.getUsername());
+        options.setPassword(mqttConfig.getPassword().toCharArray());
+        this.mqttClient.connect(options);
+    }
+
+    @PostConstruct
+    public void init() throws MqttException {
+        mqttClient.subscribe(mqttConfig.getRequestTopic(), this::handleRequest);
+        log.info("RPC Server subscribed to topic: {}", mqttConfig.getRequestTopic());
+    }
+
+    private void handleRequest(String topic, MqttMessage message) {
+        RpcRequest request = SerializationUtils.deserialize(new String(message.getPayload()), RpcRequest.class);
+        RpcResponse response = new RpcResponse();
+        response.setCorrelationId(request.getCorrelationId());
+
+        try {
+            MethodInvoker invoker = methodRegistry.get(request.getMethod());
+            if (invoker == null) {
+                throw new NoSuchMethodException("Unknown method: " + request.getMethod());
+            }
+            Object result = invoker.invoke(request.getParams());
+            response.setResult(result);
+        } catch (Exception e) {
+            response.setError(e.getMessage());
+            log.error("Error processing RPC request: {}", e.getMessage(), e);
+        }
+
+        String replyPayload = SerializationUtils.serialize(response);
+        MqttMessage replyMessage = new MqttMessage(replyPayload.getBytes());
+        replyMessage.setQos(1);
+        try {
+            mqttClient.publish(request.getReplyTo(), replyMessage);
+            log.info("Published response to {}", request.getReplyTo());
+        } catch (MqttException e) {
+            log.error("Failed to publish response: {}", e.getMessage(), e);
+        }
+    }
+
+    /**
+     * 注册可调用的方法
+     *
+     * @param methodName 方法名称
+     * @param invoker    方法调用器
+     */
+    public void registerMethod(String methodName, MethodInvoker invoker) {
+        methodRegistry.put(methodName, invoker);
+        log.info("Registered method: {}", methodName);
+    }
+
+    @PreDestroy
+    public void cleanup() throws MqttException {
+        mqttClient.disconnect();
+        log.info("RPC Server disconnected");
+    }
+
+    /**
+     * 方法调用器接口
+     */
+    @FunctionalInterface
+    public interface MethodInvoker {
+        Object invoke(Object[] params) throws Exception;
+    }
+}

yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/service/plugin/ExampleService.java

@@ -0,0 +1,43 @@
+package cn.iocoder.yudao.module.iot.service.plugin;
+
+import cn.iocoder.yudao.module.iot.mqttrpc.server.RpcServer;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import javax.annotation.PostConstruct;
+
+@Service
+@RequiredArgsConstructor
+public class ExampleService {
+
+    private final RpcServer rpcServer;
+
+    @PostConstruct
+    public void registerMethods() {
+        rpcServer.registerMethod("add", params -> {
+            if (params.length != 2) {
+                throw new IllegalArgumentException("add方法需要两个参数");
+            }
+            int a = ((Number) params[0]).intValue();
+            int b = ((Number) params[1]).intValue();
+            return add(a, b);
+        });
+
+        rpcServer.registerMethod("concat", params -> {
+            if (params.length != 2) {
+                throw new IllegalArgumentException("concat方法需要两个参数");
+            }
+            String str1 = params[0].toString();
+            String str2 = params[1].toString();
+            return concat(str1, str2);
+        });
+    }
+
+    private int add(int a, int b) {
+        return a + b;
+    }
+
+    private String concat(String a, String b) {
+        return a + b;
+    }
+}

yudao-module-iot/yudao-module-iot-biz/src/main/java/cn/iocoder/yudao/module/iot/service/plugin/PluginInfoServiceImpl.java

@@ -18,7 +18,6 @@ import org.springframework.stereotype.Service;
 import org.springframework.validation.annotation.Validated;
 import org.springframework.web.multipart.MultipartFile;
 
-import javax.annotation.PostConstruct;
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.*;