feat(relation): 实现用户关注功能并集成RocketMQ消息队列

- 新增关注用户MQ消息传输对象 FollowUserMqDTO
- 定义MQ常量类 MQConstants，包含关注/取关主题与标签
- 引入RocketMQ依赖及自动配置类 RocketMQConfig
- 在关注接口中构造并异步发送关注操作消息
- 使用JsonUtils将消息体序列化为JSON字符串
- 添加日志记录MQ发送状态及异常处理回调

han-note-user-relation/han-note-user-relation-biz/src/main/java/com/hanserwei/hannote/user/relation/biz/config/RocketMQConfig.java

@@ -0,0 +1,10 @@
+package com.hanserwei.hannote.user.relation.biz.config;
+
+import org.apache.rocketmq.spring.autoconfigure.RocketMQAutoConfiguration;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+
+@Configuration
+@Import(RocketMQAutoConfiguration.class)
+public class RocketMQConfig {
+}

han-note-user-relation/han-note-user-relation-biz/src/main/java/com/hanserwei/hannote/user/relation/biz/constant/MQConstants.java

@@ -0,0 +1,19 @@
+package com.hanserwei.hannote.user.relation.biz.constant;
+
+public interface MQConstants {
+
+    /**
+     * Topic: 关注、取关共用一个
+     */
+    String TOPIC_FOLLOW_OR_UNFOLLOW = "FollowUnfollowTopic";
+
+    /**
+     * 关注标签
+     */
+    String TAG_FOLLOW = "Follow";
+
+    /**
+     * 取关标签
+     */
+    String TAG_UNFOLLOW = "Unfollow";
+}

han-note-user-relation/han-note-user-relation-biz/src/main/java/com/hanserwei/hannote/user/relation/biz/model/dto/FollowUserMqDTO.java

@@ -0,0 +1,21 @@
+package com.hanserwei.hannote.user.relation.biz.model.dto;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+import java.time.LocalDateTime;
+
+@Data
+@AllArgsConstructor
+@NoArgsConstructor
+@Builder
+public class FollowUserMqDTO {
+
+    private Long userId;
+
+    private Long followUserId;
+
+    private LocalDateTime createTime;
+}

han-note-user-relation/han-note-user-relation-biz/src/main/java/com/hanserwei/hannote/user/relation/biz/service/impl/RelationServiceImpl.java

@@ -6,11 +6,14 @@ import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
 import com.hanserwei.framework.biz.context.holder.LoginUserContextHolder;
 import com.hanserwei.framework.common.exception.ApiException;
 import com.hanserwei.framework.common.response.Response;
+import com.hanserwei.framework.common.utils.JsonUtils;
 import com.hanserwei.hannote.user.dto.resp.FindUserByIdRspDTO;
+import com.hanserwei.hannote.user.relation.biz.constant.MQConstants;
 import com.hanserwei.hannote.user.relation.biz.constant.RedisKeyConstants;
 import com.hanserwei.hannote.user.relation.biz.domain.dataobject.FollowingDO;
 import com.hanserwei.hannote.user.relation.biz.enums.LuaResultEnum;
 import com.hanserwei.hannote.user.relation.biz.enums.ResponseCodeEnum;
+import com.hanserwei.hannote.user.relation.biz.model.dto.FollowUserMqDTO;
 import com.hanserwei.hannote.user.relation.biz.model.vo.FollowUserReqVO;
 import com.hanserwei.hannote.user.relation.biz.rpc.UserRpcService;
 import com.hanserwei.hannote.user.relation.biz.service.FollowingDOService;
@@ -18,9 +21,14 @@ import com.hanserwei.hannote.user.relation.biz.service.RelationService;
 import com.hanserwei.hannote.user.relation.biz.util.DateUtils;
 import jakarta.annotation.Resource;
 import lombok.extern.slf4j.Slf4j;
+import org.apache.rocketmq.client.producer.SendCallback;
+import org.apache.rocketmq.client.producer.SendResult;
+import org.apache.rocketmq.spring.core.RocketMQTemplate;
 import org.springframework.core.io.ClassPathResource;
 import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.data.redis.core.script.DefaultRedisScript;
+import org.springframework.messaging.Message;
+import org.springframework.messaging.support.MessageBuilder;
 import org.springframework.scripting.support.ResourceScriptSource;
 import org.springframework.stereotype.Service;
 
@@ -39,6 +47,8 @@ public class RelationServiceImpl implements RelationService {
     private RedisTemplate<Object, Object> redisTemplate;
     @Resource
     private FollowingDOService followingDOService;
+    @Resource
+    private RocketMQTemplate rocketMQTemplate;
 
     @Override
     public Response<?> follow(FollowUserReqVO followUserReqVO) {
@@ -118,7 +128,36 @@ public class RelationServiceImpl implements RelationService {
 
         }
 
-        // TODO: 发送 MQ
+        // 发送 MQ
+        // 构造消息体DTO
+        FollowUserMqDTO followUserMqDTO = FollowUserMqDTO.builder()
+                .userId(userId)
+                .followUserId(followUserId)
+                .createTime(now)
+                .build();
+        // 构造消息对象，并把DTO转换为JSON字符串设置到消息体中
+        Message<String> message = MessageBuilder
+                .withPayload(JsonUtils.toJsonString(followUserMqDTO))
+                .build();
+
+        // 通过冒号连接, 可让 MQ 发送给主题 Topic 时，携带上标签 Tag
+        String destination = MQConstants.TOPIC_FOLLOW_OR_UNFOLLOW + ":" + MQConstants.TAG_FOLLOW;
+
+        log.info("==> 开始发送关注操作 MQ, 消息体: {}", followUserMqDTO);
+
+        // 异步发送MQ消息，提升接口响应速度
+        rocketMQTemplate.asyncSend(destination, message, new SendCallback() {
+
+            @Override
+            public void onSuccess(SendResult sendResult) {
+                log.info("==> MQ 发送成功，SendResult: {}", sendResult);
+            }
+
+            @Override
+            public void onException(Throwable throwable) {
+                log.error("==> MQ 发送异常: ", throwable);
+            }
+        });
 
         return Response.success();
     }