[Feat]: 게시글 삭제 기능 구현

Author: shihan00321

back/src/main/java/com/back/domain/post/controller/PostController.java

@@ -50,4 +50,11 @@ public ResponseEntity<PostResponse> updatePost(
         Long userId = 1L; // fixme 임시 사용자 ID
         return ResponseEntity.ok(postService.updatePost(userId, postId, request));
     }
+
+    @DeleteMapping("/{postId}")
+    public ResponseEntity<Void> deletePost(@PathVariable Long postId) {
+        Long userId = 1L; // fixme 임시 사용자 ID
+        postService.deletePost(userId, postId);
+        return ResponseEntity.ok().build();
+    }
 }

back/src/main/java/com/back/domain/post/entity/Post.java

@@ -3,9 +3,12 @@
 import com.back.domain.post.enums.PostCategory;
 import com.back.domain.user.entity.User;
 import com.back.global.baseentity.BaseEntity;
+import com.back.global.exception.ApiException;
+import com.back.global.exception.ErrorCode;
 import jakarta.persistence.*;
 import lombok.*;
 import org.hibernate.annotations.ColumnDefault;
+import org.hibernate.service.spi.ServiceException;
 import org.springframework.data.annotation.LastModifiedDate;
 
 import java.time.LocalDateTime;
@@ -58,4 +61,9 @@ public void updatePost(String title, String content, PostCategory category) {
         this.content = content;
         this.category = category;
     }
+
+    public void checkUser(User targetUser) {
+        if (!user.equals(targetUser))
+            throw new ApiException(ErrorCode.UNAUTHORIZED_USER);
+    }
 }

back/src/main/java/com/back/domain/post/service/PostService.java

@@ -57,15 +57,28 @@ public List<PostResponse> getPosts() {
 
     @Transactional
     public PostResponse updatePost(Long userId, Long postId, PostRequest request) {
-        return postRepository.findById(postId)
-                .map(post -> {
-                    if (!post.getUser().getId().equals(userId)) {
-                        throw new ApiException(ErrorCode.UNAUTHORIZED_USER);
-                    }
-                    post.updatePost(request.title(), request.content(), request.category());
-                    Post updatedPost = postRepository.save(post);
-                    return PostMapper.toResponse(updatedPost);
-                })
+        Post post = validatePostOwnership(userId, postId);
+
+        post.updatePost(request.title(), request.content(), request.category());
+
+        return PostMapper.toResponse(post);
+    }
+
+    @Transactional
+    public void deletePost(Long userId, Long postId) {
+        Post post = validatePostOwnership(userId, postId);
+        postRepository.delete(post);
+    }
+
+    private Post validatePostOwnership(Long userId, Long postId) {
+        Post post = postRepository.findById(postId)
                 .orElseThrow(() -> new ApiException(ErrorCode.POST_NOT_FOUND));
+
+        User requestUser = userRepository.findById(userId)
+                .orElseThrow(() -> new ApiException(ErrorCode.USER_NOT_FOUND));
+
+        post.checkUser(requestUser);
+
+        return post;
     }
 }