fix: 조회수 한 시간 내 중복 조회 무시

fix: 조회수 한 시간 내 중복 조회 무시

Author: Yeonnies

build.gradle

@@ -61,6 +61,9 @@ dependencies {
 
 	// redis
 	implementation 'org.springframework.boot:spring-boot-starter-data-redis'
+
+	// caffeine
+	implementation 'com.github.ben-manes.caffeine:caffeine:3.1.8'
 }
 
 tasks.named('test') {

src/main/java/UMC_7th/Closit/domain/post/service/PostQueryServiceImpl.java

@@ -14,6 +14,7 @@
 import UMC_7th.Closit.domain.user.entity.User;
 import UMC_7th.Closit.global.apiPayload.code.status.ErrorStatus;
 import UMC_7th.Closit.global.apiPayload.exception.GeneralException;
+import UMC_7th.Closit.global.infra.cache.ViewBlockCacheService;
 import UMC_7th.Closit.security.SecurityUtil;
 import lombok.RequiredArgsConstructor;
 import org.springframework.data.domain.Pageable;
@@ -29,6 +30,7 @@
 @RequiredArgsConstructor
 public class PostQueryServiceImpl implements PostQueryService {
 
+    private final ViewBlockCacheService viewBlockCacheService;
     private final PostRepository postRepository;
     private final LikeRepository likeRepository;
     private final BookmarkRepository bookmarkRepository;
@@ -43,13 +45,16 @@ public class PostQueryServiceImpl implements PostQueryService {
     @Transactional // ← readOnly 제거 또는 false 설정
     public PostResponseDTO.PostPreviewDTO getPostById(Long postId) {
         User currentUser = securityUtil.getCurrentUser();
+        Long userId = currentUser.getId();
 
         // 게시글 조회
         Post post = postRepository.findById(postId)
                 .orElseThrow(() -> new GeneralException(ErrorStatus._NOT_FOUND));
 
         // 조회수 증가
-        post.increaseView();
+        if (viewBlockCacheService.shouldIncreaseView(userId, postId)) {
+            post.increaseView();
+        }
 
         // 좋아요 여부 확인
         Boolean isLiked = likeRepository.existsByUserAndPost(currentUser, post);

src/main/java/UMC_7th/Closit/global/infra/cache/ViewBlockCacheService.java

@@ -0,0 +1,24 @@
+package UMC_7th.Closit.global.infra.cache;
+
+import com.github.benmanes.caffeine.cache.Cache;
+import com.github.benmanes.caffeine.cache.Caffeine;
+import org.springframework.stereotype.Service;
+import java.util.concurrent.TimeUnit;
+
+@Service
+public class ViewBlockCacheService {
+    private final Cache<String, Boolean> viewCache = Caffeine.newBuilder()
+            .expireAfterWrite(1, TimeUnit.HOURS)  // 1시간 동안 유지
+            .maximumSize(100_000)                // 최대 캐시 크기 설정
+            .build();
+
+    public boolean shouldIncreaseView(Long userId, Long postId) {
+        String key = generateKey(userId, postId);
+        Boolean previous = viewCache.asMap().putIfAbsent(key, true);
+        return previous == null; // 이전 값이 없으면 첫 조회
+    }
+
+    private String generateKey(Long userId, Long postId) {
+        return userId + ":" + postId;
+    }
+}