Refactor: 인기글 레디스 적용

Author: leemimi

build.gradle.kts

@@ -99,6 +99,7 @@ dependencies {
         exclude(group = "org.yaml", module = "snakeyaml")
     }
     implementation("org.yaml:snakeyaml:2.0")
+    implementation("com.fasterxml.jackson.datatype:jackson-datatype-jsr310:2.18.2")
 
 }
 

src/main/java/org/com/stocknote/config/RedisConfig.java

@@ -1,13 +1,18 @@
 package org.com.stocknote.config;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationFeature;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.data.redis.connection.RedisConnectionFactory;
 import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
 import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.data.redis.core.StringRedisTemplate;
+import org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer;
 import org.springframework.data.redis.serializer.GenericToStringSerializer;
+import org.springframework.data.redis.serializer.RedisSerializer;
 import org.springframework.data.redis.serializer.StringRedisSerializer;
 
 @Configuration
@@ -17,15 +22,6 @@ public class RedisConfig {
     @Value("${spring.data.redis.port}")
     private int redisPort;
 
-    @Bean
-    public RedisTemplate<String, Object> redisTemplate() {
-        RedisTemplate<String, Object> template = new RedisTemplate<>();
-        template.setConnectionFactory(redisConnectionFactory());
-        template.setKeySerializer(new StringRedisSerializer());
-        template.setValueSerializer(new GenericToStringSerializer<>(Object.class));
-        return template;
-    }
-
     @Bean
     public RedisConnectionFactory redisConnectionFactory() {
         return new LettuceConnectionFactory(redisHost, redisPort);
@@ -44,4 +40,24 @@ public RedisTemplate<Object, Object> redisObjectTemplate() {
         redisTemplate.setValueSerializer(new StringRedisSerializer());
         return redisTemplate;
     }
+    @Bean
+    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory connectionFactory) {
+        RedisTemplate<String, Object> template = new RedisTemplate<>();
+        template.setConnectionFactory(connectionFactory);
+
+        // 🔹 JSON 직렬화 설정
+        ObjectMapper objectMapper = new ObjectMapper();
+        objectMapper.registerModule(new JavaTimeModule()); // LocalDateTime 지원 추가
+        objectMapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS); // ISO 8601 포맷 유지
+
+        RedisSerializer<Object> serializer = new GenericJackson2JsonRedisSerializer(objectMapper);
+
+        template.setKeySerializer(new StringRedisSerializer()); // 키 직렬화
+        template.setValueSerializer(serializer); // 값 직렬화
+        template.setHashKeySerializer(new StringRedisSerializer());
+        template.setHashValueSerializer(serializer);
+
+        template.afterPropertiesSet();
+        return template;
+    }
 }

src/main/java/org/com/stocknote/domain/post/dto/PostResponseDto.java

@@ -1,5 +1,6 @@
 package org.com.stocknote.domain.post.dto;
 
+import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import org.com.stocknote.domain.comment.dto.CommentDetailResponse;
 import org.com.stocknote.domain.member.entity.Member;
 import org.com.stocknote.domain.post.entity.Post;

src/main/java/org/com/stocknote/domain/post/service/PostService.java

@@ -1,6 +1,7 @@
 package org.com.stocknote.domain.post.service;
 
 import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
 import org.com.stocknote.domain.hashtag.entity.Hashtag;
 import org.com.stocknote.domain.hashtag.service.HashtagService;
 import org.com.stocknote.domain.like.repository.LikeRepository;
@@ -16,18 +17,21 @@
 import org.com.stocknote.domain.post.repository.PostRepository;
 import org.com.stocknote.domain.post.repository.PostSearchRepository;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.cache.annotation.Cacheable;
 import org.springframework.data.domain.*;
 import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.time.Duration;
 import java.time.LocalDateTime;
 import java.util.List;
 import java.util.stream.Collectors;
 
 @Service
 @RequiredArgsConstructor
+@Slf4j
 public class PostService {
     private final PostRepository postRepository;
     private final HashtagService hashtagService;
@@ -113,11 +117,22 @@ public void deletePost(Long id) {
         //댓글은 CASCADE로 삭제됨
         postRepository.delete(post);
     }
-    @Cacheable(value = POPULAR_POSTS_CACHE_KEY, key = "#pageable.pageNumber", cacheManager = "cacheManager")
+
     @Transactional(readOnly = true)
     public Page<PostResponseDto> getPopularPosts(Pageable pageable) {
-        LocalDateTime threeDaysAgo = LocalDateTime.now().minusDays(3);
+        log.info("🔥 캐시 확인: getPopularPosts 실행 (page = {})", pageable.getPageNumber());
+
+        String cacheKey = POPULAR_POSTS_CACHE_KEY + ":" + pageable.getPageNumber();
+
+        // 🔹 Redis에서 캐시된 데이터 조회
+        Object cachedData = redisTemplate.opsForValue().get(cacheKey);
+        if (cachedData instanceof Page) {
+            log.info("✅ 캐시된 데이터 반환 (page = {})", pageable.getPageNumber());
+            return (Page<PostResponseDto>) cachedData;
+        }
 
+        // 🔹 캐시된 데이터가 없으면 DB에서 조회
+        LocalDateTime threeDaysAgo = LocalDateTime.now().minusDays(3);
         Page<Post> popularPosts = postRepository.findPopularPosts(threeDaysAgo, pageable);
 
         List<PostResponseDto> sortedPosts = popularPosts.stream()
@@ -130,10 +145,16 @@ public Page<PostResponseDto> getPopularPosts(Pageable pageable) {
                 })
                 .collect(Collectors.toList());
 
-        return new PageImpl<>(sortedPosts, pageable, popularPosts.getTotalElements());
+        Page<PostResponseDto> response = new PageImpl<>(sortedPosts, pageable, popularPosts.getTotalElements());
+
+        // 🔹 Redis에 캐싱 (TTL: 5분 설정)
+        redisTemplate.opsForValue().set(cacheKey, response, Duration.ofMinutes(5));
+        log.info("🚀 새로운 데이터 Redis에 캐싱 완료 (key = {})", cacheKey);
+
+        return response;
     }
 
-    // 좋아요 순 조회
+// 좋아요 순 조회
     @Transactional(readOnly = true)
     public Page<PostResponseDto> getPopularPostsByLikes(Pageable pageable) {
         LocalDateTime sevenDaysAgo = LocalDateTime.now().minusDays(7);

src/main/java/org/com/stocknote/global/cache/service/CacheService.java

@@ -1,12 +1,14 @@
 package org.com.stocknote.global.cache.service;
 
 import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.stereotype.Service;
 
 @Service
 @RequiredArgsConstructor
 public class CacheService {
+    @Qualifier("redisTemplate")
     private final RedisTemplate<String, Object> redisTemplate;
     private static final String POPULAR_POSTS_CACHE_KEY = "popularPosts";