feat: 댓글 수정 기능 구현

Author: seok6555

src/main/java/com/back/domain/post/comment/controller/CommentController.java

@@ -1,8 +1,10 @@
 package com.back.domain.post.comment.controller;
 
 import com.back.domain.post.comment.dto.request.CommentCreateRequestDto;
+import com.back.domain.post.comment.dto.request.CommentUpdateRequestDto;
 import com.back.domain.post.comment.dto.response.CommentResponseDto;
 import com.back.domain.post.comment.service.CommentService;
+import com.back.domain.post.post.dto.request.PostUpdateRequestDto;
 import com.back.domain.post.post.dto.response.PostResponseDto;
 import com.back.global.rsData.RsData;
 import io.swagger.v3.oas.annotations.Operation;
@@ -11,6 +13,7 @@
 import java.util.List;
 import lombok.RequiredArgsConstructor;
 import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PatchMapping;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
@@ -41,6 +44,12 @@ public RsData<CommentResponseDto> createComment(
     return RsData.successOf(commentService.createComment(postId, reqBody)); // code=200, message="success"
   }
 
+  /**
+   * 댓글 다건 조회 API
+   * @param postId 댓글이 작성된 게시글 ID
+   * @param lastId 마지막으로 조회한 댓글 ID (페이징 처리용, optional)
+   * @return 댓글 목록
+   */
   @GetMapping
   @Operation(summary = "댓글 다건 조회")
   public RsData<List<CommentResponseDto>> getComments(
@@ -50,6 +59,12 @@ public RsData<List<CommentResponseDto>> getComments(
     return RsData.successOf(commentService.getComments(postId, lastId)); // code=200, message="success"
   }
 
+  /**
+   * 댓글 단건 조회 API
+   * @param postId 댓글이 작성된 게시글 ID
+   * @param commentId 조회할 댓글 ID
+   * @return 해당 ID의 댓글 정보
+   */
   @GetMapping("/{commentId}")
   @Operation(summary = "댓글 단건 조회")
   public RsData<CommentResponseDto> getComment(
@@ -58,4 +73,21 @@ public RsData<CommentResponseDto> getComment(
   ) {
     return RsData.successOf(commentService.getComment(postId, commentId)); // code=200, message="success"
   }
+
+  /**
+   * 댓글 수정 API
+   * @param postId 댓글이 작성된 게시글 ID
+   * @param commentId 수정할 댓글 ID
+   * @param reqBody 댓글 수정 요청 DTO
+   * @return 수정된 댓글 정보
+   */
+  @PatchMapping("/{commentId}")
+  @Operation(summary = "댓글 수정")
+  public RsData<CommentResponseDto> updateComment(
+      @PathVariable Long postId,
+      @PathVariable Long commentId,
+      @Valid @RequestBody CommentUpdateRequestDto reqBody
+  ) {
+    return RsData.successOf(commentService.updateComment(postId, commentId, reqBody)); // code=200, message="success"
+  }
 }

src/main/java/com/back/domain/post/comment/dto/request/CommentCreateRequestDto.java

@@ -3,7 +3,6 @@
 import jakarta.validation.constraints.NotBlank;
 
 public record CommentCreateRequestDto(
-    Long postId,
     @NotBlank (message = "내용은 필수입니다.")
     String content
 ) {

src/main/java/com/back/domain/post/comment/dto/request/CommentUpdateRequestDto.java

@@ -0,0 +1,6 @@
+package com.back.domain.post.comment.dto.request;
+
+public record CommentUpdateRequestDto(
+    String content
+) {
+}

src/main/java/com/back/domain/post/comment/entity/Comment.java

@@ -56,4 +56,8 @@ public class Comment {
   // 댓글 내용
   @Column(name = "content", nullable = false, columnDefinition = "TEXT")
   private String content;
+
+  public void updateContent(String content) {
+    this.content = content;
+  }
 }

src/main/java/com/back/domain/post/comment/service/CommentService.java

@@ -1,6 +1,7 @@
 package com.back.domain.post.comment.service;
 
 import com.back.domain.post.comment.dto.request.CommentCreateRequestDto;
+import com.back.domain.post.comment.dto.request.CommentUpdateRequestDto;
 import com.back.domain.post.comment.dto.response.CommentResponseDto;
 import com.back.domain.post.comment.entity.Comment;
 import com.back.domain.post.comment.repository.CommentRepository;
@@ -66,4 +67,24 @@ public CommentResponseDto getComment(Long postId, Long commentId) {
 
     return new CommentResponseDto(comment);
   }
+
+  // 댓글 수정 로직
+  @Transactional
+  public CommentResponseDto updateComment(Long postId, Long commentId, CommentUpdateRequestDto requestDto) {
+    User user = rq.getActor();
+
+    Comment comment = commentRepository.findById(commentId)
+        .orElseThrow(() -> new IllegalArgumentException("댓글이 존재하지 않습니다. id=" + commentId));
+
+    if (!comment.getPost().getId().equals(postId)) {
+      throw new IllegalStateException("댓글이 해당 게시글에 속하지 않습니다.");
+    }
+
+    if (!comment.getUser().equals(user)) {
+      throw new IllegalStateException("본인의 댓글만 수정할 수 있습니다.");
+    }
+
+    comment.updateContent(requestDto.content());
+    return new CommentResponseDto(comment);
+  }
 }