fix: 게시글 상세 조회 시 로그인하지 않은 사용자 예외 처리 강화

- 좋아요 여부를 직접적으로 반환받을 때 로그인 하지 않은 경우 member가 NULL이라 오류 발생
- 미리 좋아요 여부를 false로 지정해두고 null이 아닐 때만 DB에 접근하게 변경

src/main/java/com/solucitation/midpoint_backend/domain/community_board/api/PostController.java

@@ -70,14 +70,14 @@ public ResponseEntity<?> getAllPosts(Authentication authentication) {
     @GetMapping("/{postId}")
     public ResponseEntity<?> getPost(@PathVariable Long postId, Authentication authentication) {
         try {
-            Member member = null;
+            Member read_member = null;
 
             if (!(authentication == null || !authentication.isAuthenticated())) {
                 String memberEmail = authentication.getName();
-                member = memberService.getMemberByEmail(memberEmail);
+                read_member = memberService.getMemberByEmail(memberEmail);
             }
 
-            PostDetailDto postDetailDto = postService.getPostById(postId, member);
+            PostDetailDto postDetailDto = postService.getPostById(postId, read_member);
             return ResponseEntity.ok(postDetailDto);
         } catch (EntityNotFoundException e) {
             return ResponseEntity.status(HttpStatus.NOT_FOUND).body("해당 게시글이 존재하지 않습니다.");

src/main/java/com/solucitation/midpoint_backend/domain/community_board/service/PostService.java

@@ -35,7 +35,7 @@ public class PostService {
     private final PostHashtagRepository postHashtagsRepository;
 
     @Transactional(readOnly = true)
-    public PostDetailDto getPostById(Long postId, Member member) {
+    public PostDetailDto getPostById(Long postId, Member read_member) {
         Post post = postRepository.findById(postId).orElseThrow(EntityNotFoundException::new);
         String memberEmail = post.getMember().getEmail();
 
@@ -52,6 +52,11 @@ public PostDetailDto getPostById(Long postId, Member member) {
 
         int likeCnt = likesRepository.countByPostIdAndIsLiked(postId);
 
+        Boolean likes = false;
+        if (read_member != null) {
+            likes = likesRepository.isMemberLikesPostByEmail(post.getId(), read_member.getEmail());
+        }
+
         return new PostDetailDto(
                 memberProfileResponseDto.getNickname(),
                 memberProfileResponseDto.getProfileImageUrl(),
@@ -61,7 +66,7 @@ public PostDetailDto getPostById(Long postId, Member member) {
                 hashtags,
                 images,
                 likeCnt,
-                likesRepository.isMemberLikesPostByEmail(post.getId(), member.getEmail())
+                likes
         );
     }