feat: 댓글 기능 추가

src/main/java/com/unit/daybook/domain/board/dto/response/FindOneBoardResponse.java

@@ -5,6 +5,7 @@
 
 import com.unit.daybook.domain.board.entity.Board;
 import com.unit.daybook.domain.board.entity.Hashtag;
+import com.unit.daybook.domain.comment.dto.response.FindOneCommentResponse;
 import com.unit.daybook.domain.reaction.dto.response.ReactionTypeAndCount;
 import com.unit.daybook.domain.reaction.entity.Reaction;
 
@@ -19,9 +20,10 @@ public record FindOneBoardResponse(
 	List<String> hashtags,
 	String paperType,
 	List<ReactionTypeAndCount> reactions,
+	List<FindOneCommentResponse> comments,
 	LocalDateTime createdAt
 ) {
-	public static FindOneBoardResponse of(Board board, List<ReactionTypeAndCount> reactions) {
+	public static FindOneBoardResponse of(Board board, List<ReactionTypeAndCount> reactions, List<FindOneCommentResponse> comments) {
 		List<String> hashContents = board.getHashtags().stream().map(Hashtag::getContent).toList();
 		Long heartsFromReactions = reactions.stream().mapToLong(ReactionTypeAndCount::count).sum();
 		return new FindOneBoardResponse(
@@ -34,6 +36,7 @@ public static FindOneBoardResponse of(Board board, List<ReactionTypeAndCount> re
 			hashContents,
 			board.getPaperType(),
 			reactions,
+			comments,
 			board.getCreatedAt()
 		);
 	}

src/main/java/com/unit/daybook/domain/board/entity/Board.java

@@ -1,6 +1,7 @@
 package com.unit.daybook.domain.board.entity;
 
 import com.unit.daybook.domain.board.dto.request.AddBoardRequestDto;
+import com.unit.daybook.domain.comment.entity.Comment;
 import com.unit.daybook.domain.common.model.BaseTimeEntity;
 import com.unit.daybook.domain.member.domain.Member;
 import com.unit.daybook.domain.reaction.entity.Reaction;
@@ -42,12 +43,15 @@ public class Board extends BaseTimeEntity {
     @Column
     private Long hearts;
 
-    @OneToMany(mappedBy = "board", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "board", cascade = CascadeType.ALL, orphanRemoval = true)
     private List<Hashtag> hashtags = new ArrayList<>();
 
-    @OneToMany(mappedBy = "board", cascade = CascadeType.REMOVE)
+    @OneToMany(mappedBy = "board", cascade = CascadeType.ALL, orphanRemoval = true)
     private List<Reaction> reactions = new ArrayList<>();
 
+    @OneToMany(mappedBy = "board", cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<Comment> comments = new ArrayList<>();
+
     @Builder(access = AccessLevel.PRIVATE)
     public Board(Long boardId, String content, Long respectBoardId, Member member, String category, Long hearts, String paperType) {
         this.boardId = boardId;

src/main/java/com/unit/daybook/domain/board/entity/Hashtag.java

@@ -2,6 +2,7 @@
 
 
 import com.unit.daybook.domain.board.dto.request.AddBoardRequestDto;
+import com.unit.daybook.domain.common.model.BaseTimeEntity;
 import com.unit.daybook.domain.member.domain.Member;
 import jakarta.persistence.*;
 import lombok.AccessLevel;
@@ -15,7 +16,7 @@
 @Entity
 @Table(name = "hashtag")
 @NoArgsConstructor(access = AccessLevel.PROTECTED)
-public class Hashtag {
+public class Hashtag extends BaseTimeEntity {
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     @Column(name = "hashtag_id")

src/main/java/com/unit/daybook/domain/board/service/BoardService.java

@@ -10,6 +10,9 @@
 import com.unit.daybook.domain.board.entity.ReadBoard;
 import com.unit.daybook.domain.board.repository.*;
 
+import com.unit.daybook.domain.comment.dto.response.FindOneCommentResponse;
+import com.unit.daybook.domain.comment.entity.Comment;
+import com.unit.daybook.domain.comment.repository.CommentRepository;
 import com.unit.daybook.domain.member.domain.Member;
 import com.unit.daybook.domain.member.repository.MemberRepository;
 import com.unit.daybook.domain.reaction.dto.response.ReactionTypeAndCount;
@@ -33,6 +36,7 @@ public class BoardService {
     private final ReadBoardRepository readBoardRepository;
     private final HashtagRepository hashtagRepository;
     private final ReactionRepository reactionRepository;
+    private final CommentRepository commentRepository;
 
     public BoardResponseDto addBoard(AddBoardRequestDto addBoardRequestDto, Long memberId) {
         Member member = memberRepository
@@ -60,8 +64,11 @@ public FindOneBoardResponse getBoard(Long boardId) {
         Board board = boardRepository.findById(boardId)
             .orElseThrow(() -> new CustomException(ErrorCode.BOARD_NOT_FOUND));
         List<ReactionTypeAndCount> reactions = reactionRepository.findAllByBoardGroupByReactionType(board);
-
-        return FindOneBoardResponse.of(board, reactions);
+        List<FindOneCommentResponse> comments = commentRepository.findCommentByBoard(boardId)
+            .stream()
+            .map(FindOneCommentResponse::from)
+            .toList();
+        return FindOneBoardResponse.of(board, reactions, comments);
     }
 
     @Transactional(readOnly = true)

src/main/java/com/unit/daybook/domain/comment/controller/CommentController.java

@@ -0,0 +1,54 @@
+package com.unit.daybook.domain.comment.controller;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.PutMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.unit.daybook.domain.comment.dto.request.CommentCreateRequest;
+import com.unit.daybook.domain.comment.dto.request.CommentModifyRequest;
+import com.unit.daybook.domain.comment.dto.response.CommentCreateResponse;
+import com.unit.daybook.domain.comment.dto.response.CommentModifyResponse;
+import com.unit.daybook.domain.comment.service.CommentService;
+import com.unit.daybook.domain.common.annotation.LoginUsers;
+import com.unit.daybook.global.config.security.CustomUserDetails;
+
+import jakarta.validation.Valid;
+import lombok.RequiredArgsConstructor;
+
+@RestController
+@RequestMapping("/comments")
+@RequiredArgsConstructor
+public class CommentController {
+
+	private final CommentService commentService;
+
+	@PostMapping
+	public ResponseEntity<CommentCreateResponse> commentCreate(
+		@Valid @RequestBody CommentCreateRequest request,
+		@LoginUsers CustomUserDetails userDetails
+	) {
+		CommentCreateResponse comment = commentService.createComment(request, userDetails.getMemberId());
+		return ResponseEntity.status(HttpStatus.CREATED).body(comment);
+	}
+
+	@DeleteMapping("/{commentId}")
+	public void commentDelete(
+		@PathVariable Long commentId
+	) {
+		commentService.deleteComment(commentId);
+	}
+
+	@PutMapping("/{commentId}")
+	public CommentModifyResponse commentModify(
+		@Valid @RequestBody CommentModifyRequest request,
+		@PathVariable Long commentId
+	) {
+		return commentService.updateComment(request, commentId);
+	}
+}

src/main/java/com/unit/daybook/domain/comment/dto/request/CommentCreateRequest.java

@@ -0,0 +1,7 @@
+package com.unit.daybook.domain.comment.dto.request;
+
+public record CommentCreateRequest (
+	String content,
+	Long boardId
+) {
+}

src/main/java/com/unit/daybook/domain/comment/dto/request/CommentModifyRequest.java

@@ -0,0 +1,6 @@
+package com.unit.daybook.domain.comment.dto.request;
+
+public record CommentModifyRequest(
+	String content
+) {
+}

src/main/java/com/unit/daybook/domain/comment/dto/response/CommentCreateResponse.java

@@ -0,0 +1,19 @@
+package com.unit.daybook.domain.comment.dto.response;
+
+import com.unit.daybook.domain.comment.entity.Comment;
+
+public record CommentCreateResponse(
+	Long commentId,
+	String content,
+	Long boardId,
+	Long memberId
+) {
+	public static CommentCreateResponse from(Comment comment) {
+		return new CommentCreateResponse(
+			comment.getCommentId(),
+			comment.getContent(),
+			comment.getBoard().getBoardId(),
+			comment.getMember().getId()
+		);
+	}
+}

src/main/java/com/unit/daybook/domain/comment/dto/response/CommentModifyResponse.java

@@ -0,0 +1,12 @@
+package com.unit.daybook.domain.comment.dto.response;
+
+import com.unit.daybook.domain.comment.entity.Comment;
+
+public record CommentModifyResponse(
+	String content,
+	Long commentId
+) {
+	public static CommentModifyResponse from(Comment comment) {
+		return new CommentModifyResponse(comment.getContent(), comment.getCommentId());
+	}
+}

src/main/java/com/unit/daybook/domain/comment/dto/response/FindOneCommentResponse.java

@@ -0,0 +1,12 @@
+package com.unit.daybook.domain.comment.dto.response;
+
+import com.unit.daybook.domain.comment.entity.Comment;
+
+public record FindOneCommentResponse(
+	Long commentId,
+	String content
+) {
+	public static FindOneCommentResponse from(Comment comment) {
+		return new FindOneCommentResponse(comment.getCommentId(), comment.getContent());
+	}
+}

src/main/java/com/unit/daybook/domain/comment/entity/Comment.java

@@ -1,22 +1,63 @@
 package com.unit.daybook.domain.comment.entity;
 
-import jakarta.persistence.*;
+import com.unit.daybook.domain.board.entity.Board;
+import com.unit.daybook.domain.common.model.BaseTimeEntity;
+import com.unit.daybook.domain.member.domain.Member;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.Table;
 import lombok.AccessLevel;
+import lombok.Builder;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
 
-//@Getter
-//@Entity
-//@Table(name = "comment")
-//@NoArgsConstructor(access = AccessLevel.PROTECTED)
-//public class Comment {
-//
-//    @Id
-//    @GeneratedValue(strategy = GenerationType.IDENTITY)
-//    @Column(name = "comment_id")
-//    private Long commentId;
-//
-//    @Column
-//    private String content;
-//
-//}
+@Getter
+@Entity
+@Table(name = "comment")
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+public class Comment extends BaseTimeEntity {
+
+   @Id
+   @GeneratedValue(strategy = GenerationType.IDENTITY)
+   @Column(name = "comment_id")
+   private Long commentId;
+
+	@Column(nullable = false, length = 25)
+   private String content;
+
+   @ManyToOne(fetch = FetchType.LAZY)
+   @JoinColumn(name = "member_id")
+   private Member member;
+
+   @ManyToOne(fetch = FetchType.LAZY)
+   @JoinColumn(name = "board_id")
+   private Board board;
+
+	@Builder(access = AccessLevel.PRIVATE)
+	private Comment(String content, Member member, Board board) {
+		this.content = content;
+		this.member = member;
+		this.board = board;
+	}
+
+	public static Comment createComment(
+		String content, Member member, Board board
+	) {
+		return Comment.builder()
+			.content(content)
+			.member(member)
+			.board(board)
+			.build();
+	}
+
+	public void updateContent(String content) {
+		this.content = content;
+	}
+}

src/main/java/com/unit/daybook/domain/comment/repository/CommentRepository.java

@@ -0,0 +1,8 @@
+package com.unit.daybook.domain.comment.repository;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import com.unit.daybook.domain.comment.entity.Comment;
+
+public interface CommentRepository extends JpaRepository<Comment, Long>, CommentRepositoryCustom {
+}

src/main/java/com/unit/daybook/domain/comment/repository/CommentRepositoryCustom.java

@@ -0,0 +1,10 @@
+package com.unit.daybook.domain.comment.repository;
+
+import java.util.List;
+
+import com.unit.daybook.domain.comment.dto.response.FindOneCommentResponse;
+import com.unit.daybook.domain.comment.entity.Comment;
+
+public interface CommentRepositoryCustom {
+	List<Comment> findCommentByBoard(Long boardId);
+}

src/main/java/com/unit/daybook/domain/comment/repository/CommentRepositoryImpl.java

@@ -0,0 +1,30 @@
+package com.unit.daybook.domain.comment.repository;
+
+import static com.unit.daybook.domain.board.entity.QBoard.*;
+import static com.unit.daybook.domain.comment.entity.QComment.*;
+
+import java.util.List;
+
+import org.springframework.stereotype.Repository;
+
+import com.querydsl.jpa.impl.JPAQueryFactory;
+import com.unit.daybook.domain.comment.entity.Comment;
+
+import lombok.RequiredArgsConstructor;
+
+@Repository
+@RequiredArgsConstructor
+public class CommentRepositoryImpl implements CommentRepositoryCustom{
+
+	private final JPAQueryFactory jpaQueryFactory;
+
+	@Override
+	public List<Comment> findCommentByBoard(Long boardId) {
+		return jpaQueryFactory.selectFrom(comment)
+			.leftJoin(comment.board, board)
+			.fetchJoin()
+			.where(board.boardId.eq(boardId))
+			.orderBy(comment.createdAt.desc())
+			.fetch();
+	}
+}