feat: 댓글 삭제 API 구현

Author: dnzp75

src/main/java/com/example/log4u/domain/comment/controller/CommentController.java

@@ -31,4 +31,12 @@ public ResponseEntity<CommentCreateResponseDto> addComment(@RequestBody @Valid C
 		CommentCreateResponseDto response = commentService.addComment(userId, requestDto);
 		return ResponseEntity.ok(response);
 	}
+
+	@DeleteMapping("/{commentId}")
+	public ResponseEntity<Void> deleteComment(@PathVariable Long commentId) {
+		Long userId = 1L; //임시 처리
+
+		commentService.deleteComment(userId, commentId);
+		return ResponseEntity.noContent().build();
+	}
 }

src/main/java/com/example/log4u/domain/comment/exception/UnauthorizedAccessException.java

@@ -0,0 +1,7 @@
+package com.example.log4u.domain.comment.exception;
+
+public class UnauthorizedAccessException extends CommentException {
+	public UnauthorizedAccessException() {
+		super(CommentErrorCode.UNAUTHORIZED_COMMENT_ACCESS);
+	}
+}

src/main/java/com/example/log4u/domain/comment/service/CommentService.java

@@ -20,14 +20,33 @@ public class CommentService {
 	private final CommentRepository commentRepository;
 	private final DiaryService diaryService;
 
+	@Transactional
 	public CommentCreateResponseDto addComment(Long userId, CommentCreateRequestDto requestDto) {
 		checkDiaryExists(requestDto);
 		Comment comment = requestDto.toEntity(userId);
 		commentRepository.save(comment);
 		return CommentCreateResponseDto.of(comment);
 	}
 
+	@Transactional
+	public void deleteComment(Long userId, Long commentId) {
+		Comment comment = getComment(commentId);
+		validateCommentOwner(userId, comment);
+		commentRepository.delete(comment);
+	}
+
 	private void checkDiaryExists(CommentCreateRequestDto requestDto) {
 		diaryService.checkDiaryExists(requestDto.diaryId());
 	}
+
+	private void validateCommentOwner(Long userId, Comment comment) {
+		if (!comment.getUserId().equals(userId)) {
+			throw new UnauthorizedAccessException();
+		}
+	}
+
+	private Comment getComment(Long commentId) {
+		return commentRepository.findById(commentId)
+			.orElseThrow(NotFoundCommentException::new);
+	}
 }