Merge pull request #48 from IT-Cotato/feat/47-post

[FEATURE] 게시글 스크랩 추가/삭제 & 마이페이지 스크랩 게시글 조회

src/main/java/com/cotato/kampus/domain/post/api/PostController.java

@@ -86,7 +86,7 @@ public ResponseEntity<DataResponse<PostDetailResponse>> findPostDetail(
 	}
 
 	@DeleteMapping("/{postId}")
-	@Operation(summary = "게시글 삭제", description = "postId를 통해 게시글 삭제")
+	@Operation(summary = "게시글 삭제", description = "(현재 유저가 작성한 게시글일 경우) 게시글을 삭제합니다.")
 	public ResponseEntity<DataResponse<PostDeleteResponse>> deletePost(
 		@PathVariable Long postId
 	) {
@@ -122,13 +122,45 @@ public ResponseEntity<DataResponse<MyPostResponse>> findMyPosts(
 			)
 		);
 	}
-
-	@PostMapping("/{postId}/likes")
+  
+  @PostMapping("/{postId}/likes")
 	@Operation(summary = "게시글 좋아요", description = "게시글 좋아요")
 	public ResponseEntity<DataResponse<Void>> likePost(
 		@PathVariable Long postId
 	) {
 		postService.likePost(postId);
 		return ResponseEntity.ok(DataResponse.ok());
 	}
+
+	@PostMapping("/{postId}/scrap")
+	@Operation(summary = "게시글 스크랩", description = "게시글을 스크랩합니다.")
+	public ResponseEntity<DataResponse<Void>> scrapPost(
+		@PathVariable Long postId
+	){
+		postService.scrapPost(postId);
+		return ResponseEntity.ok(DataResponse.ok());
+	}
+
+	@DeleteMapping("/{postId}/scrap")
+	@Operation(summary = "게시글 스크랩 취소", description = "게시글 스크랩을 해제합니다.")
+	public ResponseEntity<DataResponse<Void>> unscrapPost(
+		@PathVariable Long postId
+	){
+		postService.unscrapPost(postId);
+		return ResponseEntity.ok(DataResponse.ok());
+	}
+
+	@GetMapping("/my/scrap")
+	@Operation(summary = "[마이페이지] 스크랩한 게시글 조회", description = "현재 사용자가 스크랩한 게시글을 최신순으로 조회합니다.")
+	public ResponseEntity<DataResponse<MyPostResponse>> findMyScrapedPosts(
+		@RequestParam(required = false, defaultValue = "0") int page
+	){
+		return ResponseEntity.ok(DataResponse.from(
+				MyPostResponse.from(
+					postService.findUserScrapedPosts(page)
+				)
+			)
+		);
+	}
+
 }

src/main/java/com/cotato/kampus/domain/post/application/PostAuthorResolver.java

@@ -45,5 +45,6 @@ public Boolean validatePostAuthor(Long postId, Long userId) {
 		PostDto post = postFinder.findPost(postId);
 
 		return post.userId().equals(userId);
+
 	}
 }

src/main/java/com/cotato/kampus/domain/post/application/PostFinder.java

@@ -14,8 +14,10 @@
 import com.cotato.kampus.domain.common.application.ApiUserResolver;
 import com.cotato.kampus.domain.post.dao.PostPhotoRepository;
 import com.cotato.kampus.domain.post.dao.PostRepository;
+import com.cotato.kampus.domain.post.dao.PostScrapRepository;
 import com.cotato.kampus.domain.post.domain.Post;
 import com.cotato.kampus.domain.post.domain.PostPhoto;
+import com.cotato.kampus.domain.post.domain.PostScrap;
 import com.cotato.kampus.domain.post.dto.MyPostWithPhoto;
 import com.cotato.kampus.domain.post.dto.PostDto;
 import com.cotato.kampus.domain.post.dto.PostWithPhotos;
@@ -37,18 +39,13 @@ public class PostFinder {
 	public static final String SORT_PROPERTY = "createdTime";
 	private final ApiUserResolver apiUserResolver;
 	private final BoardFinder boardFinder;
+	private final PostScrapRepository postScrapRepository;
 
 	public Post getPost(Long postId) {
 		return postRepository.findById(postId)
 			.orElseThrow(() -> new AppException(ErrorCode.POST_NOT_FOUND));
 	}
 
-	public Long getAuthorId(Long postId) {
-		Post post = postRepository.findById(postId)
-			.orElseThrow(() -> new AppException(ErrorCode.POST_NOT_FOUND));
-
-		return post.getUserId();
-	}
 
 	public Slice<PostWithPhotos> findPosts(Long boardId, int page) {
 		// 1. Post 리스트를 Slice로 조회
@@ -89,4 +86,25 @@ public Slice<MyPostWithPhoto> findUserPosts(int page){
 			return MyPostWithPhoto.from(post, boardName, postPhoto);
 		});
 	}
+
+	public Slice<MyPostWithPhoto> findUserScrapedPosts(int page){
+
+		Long userId = apiUserResolver.getUserId();
+		CustomPageRequest customPageRequest = new CustomPageRequest(page, PAGE_SIZE, Sort.Direction.DESC);
+
+		// 스크랩된 포스트만 조회
+		Slice<PostScrap> postScraps = postScrapRepository.findAllByUserId(userId, customPageRequest.of(SORT_PROPERTY));
+
+		// 스크랩된 포스트에 해당하는 Post를 찾아서 반환
+		return postScraps.map(postScrap -> {
+			Post post = getPost(postScrap.getPostId());
+
+			String boardName = boardFinder.findBoard(post.getBoardId()).getBoardName();
+
+			PostPhoto postPhoto = postPhotoRepository.findFirstByPostIdOrderByCreatedTimeAsc(post.getId())
+				.orElse(null);
+
+			return MyPostWithPhoto.from(post, boardName, postPhoto);
+		});
+	}
 }

src/main/java/com/cotato/kampus/domain/post/application/PostScrapUpdater.java

@@ -0,0 +1,36 @@
+package com.cotato.kampus.domain.post.application;
+
+import org.springframework.stereotype.Component;
+import org.springframework.transaction.annotation.Transactional;
+
+import com.cotato.kampus.domain.post.dao.PostScrapRepository;
+import com.cotato.kampus.domain.post.domain.PostScrap;
+import com.cotato.kampus.global.error.ErrorCode;
+import com.cotato.kampus.global.error.exception.AppException;
+
+import lombok.AccessLevel;
+import lombok.RequiredArgsConstructor;
+
+@Component
+@Transactional(readOnly = true)
+@RequiredArgsConstructor(access = AccessLevel.PROTECTED)
+public class PostScrapUpdater {
+
+	private final PostScrapRepository postScrapRepository;
+
+	public void append(Long postId, Long userId) {
+		PostScrap postScrap = PostScrap.builder()
+			.postId(postId)
+			.userId(userId)
+			.build();
+
+		postScrapRepository.save(postScrap);
+	}
+
+	public void delete(Long postId, Long userId) {
+		PostScrap postScrap = postScrapRepository.findByUserIdAndPostId(userId, postId)
+			.orElseThrow(() -> new AppException(ErrorCode.POST_SCRAP_NOT_EXIST));
+
+		postScrapRepository.delete(postScrap);
+	}
+}

src/main/java/com/cotato/kampus/domain/post/application/PostScrapValidator.java

@@ -0,0 +1,33 @@
+package com.cotato.kampus.domain.post.application;
+
+import org.springframework.stereotype.Component;
+import org.springframework.transaction.annotation.Transactional;
+
+import com.cotato.kampus.domain.post.dao.PostScrapRepository;
+import com.cotato.kampus.global.error.ErrorCode;
+import com.cotato.kampus.global.error.exception.AppException;
+
+import lombok.AccessLevel;
+import lombok.RequiredArgsConstructor;
+
+@Component
+@Transactional(readOnly = true)
+@RequiredArgsConstructor(access = AccessLevel.PROTECTED)
+public class PostScrapValidator {
+
+	private final PostScrapRepository postScrapRepository;
+	private final PostAuthorResolver postAuthorResolver;
+
+	public void validatePostScrap(Long postId, Long userId){
+		Long authorId = postAuthorResolver.getAuthorId(postId);
+
+		// 본인 게시글 또는 이미 스크랩한 게시글은 예외처리
+		if(userId.equals(authorId)){
+			throw new AppException(ErrorCode.POST_SCRAP_FORBIDDEN);
+		}
+
+		if(postScrapRepository.existsByUserIdAndPostId(userId, postId)){
+			throw new AppException(ErrorCode.POST_SCRAP_DUPLICATED);
+		}
+	}
+}

src/main/java/com/cotato/kampus/domain/post/application/PostService.java

@@ -31,16 +31,20 @@ public class PostService {
 	private final PostFinder postFinder;
 	private final PostUpdater postUpdater;
 
+	private final PostAuthorResolver postAuthorResolver;
+	private static final String POST_IMAGE_FOLDER = "post";
 
 	private final PostImageAppender postImageAppender;
 	private final PostImageFinder postImageFinder;
 	private final PostImageUpdater postImageUpdater;
-
-	private final PostAuthorResolver postAuthorResolver;
+  
+	private final PostScrapUpdater postScrapUpdater;
 	private final ApiUserResolver apiUserResolver;
 	private final S3Uploader s3Uploader;
 
+  private final UserValidator userValidator;
 	private final ImageValidator imageValidator;
+	private final PostScrapValidator postScrapValidator;
 	private final UserValidator userValidator;
 	private final PostLikeAppender postLikeAppender;
 	private final PostLikeValidator postLikeValidator;
@@ -79,7 +83,10 @@ public Long createPost(
 	@Transactional
 	public Long deletePost(Long postId) {
 		// 작성자 검증: 현재 사용자가 게시글 작성자인지 확인
-		userValidator.validatePostAuthor(postId);
+		Long userId = apiUserResolver.getUserId();
+		Long authorId = postAuthorResolver.getAuthorId(postId);
+
+		userValidator.validatePostAuthor(authorId, userId);
 
 		// 게시글 삭제
 		postDeleter.delete(postId);
@@ -110,7 +117,7 @@ public void updatePost(Long postId, String title, String content, PostCategory p
 		List<MultipartFile> images) throws ImageException {
 		// 1. Post Author 검증
 		Long userId = apiUserResolver.getUserId();
-		postAuthorResolver.validatePostAuthor(postId, userId);
+		userValidator.validatePostAuthor(postId, userId);
 
 		// 2. Post 업데이트
 		postUpdater.updatePost(postId, title, content, postCategory, anonymity);
@@ -137,4 +144,33 @@ public void likePost(Long postId) {
 	public Slice<MyPostWithPhoto> findUserPosts(int page) {
 		return postFinder.findUserPosts(page);
 	}
+
+	@Transactional
+	public void scrapPost(Long postId){
+		// 스크랩 가능 여부 검증
+		Long userId = apiUserResolver.getUserId();
+		postScrapValidator.validatePostScrap(postId, userId);
+
+		// 게시글 스크랩 수 추가
+		postUpdater.increaseScraps(postId);
+
+		// 스크랩 데이터 추가
+		postScrapUpdater.append(postId, userId);
+	}
+
+	@Transactional
+	public void unscrapPost(Long postId){
+		// 유저 조회
+		Long userId = apiUserResolver.getUserId();
+
+		// 게시글 스크랩 수 감소
+		postUpdater.decreaseScraps(postId);
+
+		// 스크랩 데이터 삭제
+		postScrapUpdater.delete(postId, userId);
+	}
+
+	public Slice<MyPostWithPhoto> findUserScrapedPosts(int page){
+		return postFinder.findUserScrapedPosts(page);
+	}
 }

src/main/java/com/cotato/kampus/domain/post/application/PostUpdater.java

@@ -47,4 +47,22 @@ public Long increaseNextAnonymousNumber(Long postId) {
 
 		return currentAnonymousNumber;
 	}
+
+	@Transactional
+	public void increaseScraps(Long postId){
+
+		Post post = postFinder.getPost(postId);
+		post.increaseScraps();
+
+		postRepository.save(post);
+	}
+
+	@Transactional
+	public void decreaseScraps(Long postId){
+
+		Post post = postFinder.getPost(postId);
+		post.decreaseScraps();
+
+		postRepository.save(post);
+	}
 }

src/main/java/com/cotato/kampus/domain/post/dao/PostScrapRepository.java

@@ -0,0 +1,18 @@
+package com.cotato.kampus.domain.post.dao;
+
+import java.util.Optional;
+
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.domain.Slice;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import com.cotato.kampus.domain.post.domain.PostScrap;
+
+public interface PostScrapRepository extends JpaRepository<PostScrap, Long> {
+
+	boolean existsByUserIdAndPostId(Long userId, Long postId);
+
+	Optional<PostScrap> findByUserIdAndPostId(Long userId, Long postId);
+
+	Slice<PostScrap> findAllByUserId(Long userId, Pageable pageable);
+}

src/main/java/com/cotato/kampus/domain/post/domain/Post.java

@@ -58,6 +58,7 @@ public class Post extends BaseTimeEntity {
 	@Column(name = "post_status", nullable = false)
 	private PostStatus postStatus;
 
+	@Enumerated(EnumType.STRING)
 	@Column(name = "post_category", nullable = false)
 	private PostCategory postCategory;
 
@@ -85,10 +86,18 @@ public void update(String title, String content, PostCategory postCategory, Anon
 		this.content = content;
 		this.postCategory = postCategory;
 		this.anonymity = anonymity;
+  	}
+
+  public void increaseNextAnonymousNumber(){
+			this.nextAnonymousNumber++;
+	}
+
+	public void increaseScraps() {
+		this.scraps++;
 	}
 
-	public void increaseNextAnonymousNumber() {
-		this.nextAnonymousNumber++;
+	public void decreaseScraps() {
+		this.scraps--;
 	}
 
 	public void increaseLikes() {

src/main/java/com/cotato/kampus/domain/post/domain/PostScrap.java

@@ -0,0 +1,38 @@
+package com.cotato.kampus.domain.post.domain;
+
+import com.cotato.kampus.domain.common.domain.BaseTimeEntity;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.Table;
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Entity
+@Table(name = "post_scrap")
+@Getter
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+public class PostScrap extends BaseTimeEntity {
+
+	@Id
+	@GeneratedValue(strategy = GenerationType.IDENTITY)
+	@Column(name = "post_scrap_id")
+	private Long id;
+
+	@Column(name = "user_id", nullable = false)
+	private Long userId;
+
+	@Column(name = "post_id", nullable = false)
+	private Long postId;
+
+	@Builder
+	public PostScrap(Long userId, Long postId) {
+		this.userId = userId;
+		this.postId = postId;
+	}
+}