feat(count): 新增笔记评论数缓存更新逻辑

- 在 CountNoteCommentConsumer 中引入 RedisTemplate依赖
- 消费评论消息时，更新 Redis 中笔记评论总数
- 新增 RedisKeyConstants.FIELD_COMMENT_TOTAL 常量定义
- 实现基于 Hash 的评论数累加更新机制
- 优化评论数更新流程，支持批量处理与缓存同步

han-note-count/han-note-count-biz/src/main/java/com/hanserwei/hannote/count/biz/constant/RedisKeyConstants.java

@@ -31,6 +31,11 @@ public class RedisKeyConstants {
      */
     private static final String COUNT_NOTE_KEY_PREFIX = "count:note:";
 
+    /**
+     * Hash Field: 笔记评论总数
+     */
+    public static final String FIELD_COMMENT_TOTAL = "commentTotal";
+
     /**
      * Hash Field: 笔记收藏总数
      */

han-note-count/han-note-count-biz/src/main/java/com/hanserwei/hannote/count/biz/consumer/CountNoteCommentConsumer.java

@@ -5,12 +5,14 @@ import com.github.phantomthief.collection.BufferTrigger;
 import com.google.common.collect.Lists;
 import com.hanserwei.framework.common.utils.JsonUtils;
 import com.hanserwei.hannote.count.biz.constant.MQConstants;
+import com.hanserwei.hannote.count.biz.constant.RedisKeyConstants;
 import com.hanserwei.hannote.count.biz.domain.mapper.NoteCountDOMapper;
 import com.hanserwei.hannote.count.biz.model.dto.CountPublishCommentMqDTO;
 import jakarta.annotation.Resource;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.rocketmq.spring.annotation.RocketMQMessageListener;
 import org.apache.rocketmq.spring.core.RocketMQListener;
+import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.stereotype.Component;
 
 import java.time.Duration;
@@ -27,6 +29,8 @@ public class CountNoteCommentConsumer implements RocketMQListener<String> {
 
     @Resource
     private NoteCountDOMapper noteCountDOMapper;
+    @Resource
+    private RedisTemplate<String, Object> redisTemplate;
 
     private final BufferTrigger<String> bufferTrigger = BufferTrigger.<String>batchBlocking()
             .bufferSize(50000) // 缓存队列的最大容量
@@ -67,6 +71,19 @@ public class CountNoteCommentConsumer implements RocketMQListener<String> {
             // 评论数
             int count = CollUtil.size(entry.getValue());
 
+            // 更新 Redis 缓存中的笔记评论总数
+            // 构建 Key
+            String noteCountHashKey = RedisKeyConstants.buildCountNoteKey(noteId);
+            // 判断 Hash 是否存在
+            boolean hasKey = redisTemplate.hasKey(noteCountHashKey);
+
+            // 若 Hash 存在
+            if (hasKey) {
+                // 累加更新
+                redisTemplate.opsForHash()
+                        .increment(noteCountHashKey, RedisKeyConstants.FIELD_COMMENT_TOTAL, count);
+            }
+
             // 若评论数大于零，则执行更新操作：累加评论总数
             if (count > 0) {
                 noteCountDOMapper.insertOrUpdateCommentTotalByNoteId(count, noteId);