[Spring] @OneToMany 댓글 삭제 권한부여, 삭제

1. View 확인

            {{#board.replies}}
                <!-- 댓글아이템 -->
                <div class="list-group-item d-flex justify-content-between align-items-center">
                    <div class="d-flex">
                        <div class="px-1 me-1 bg-primary text-white rounded">{{user.username}}</div>
                        <div>{{comment}}</div>
                    </div>
                    <form action="/reply/{{id}}/delete" method="post">
                        <button class="btn">🗑</button>
                    </form>
                </div>
            {{/board.replies}}

2. 권한부여하기

package shop.mtcoding.blog.reply;

import jakarta.persistence.*;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.hibernate.annotations.CreationTimestamp;
import shop.mtcoding.blog.board.Board;
import shop.mtcoding.blog.user.User;

import java.time.LocalDateTime;

@NoArgsConstructor  // 빈생성자가 필요
@Entity
@Data
@Table(name = "reply_tb")
public class Reply {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id ;

    private String comment;
    //user_id 로 테이블 만들어짐.
    @ManyToOne(fetch = FetchType.LAZY)
    private User user ;

    @ManyToOne(fetch = FetchType.LAZY)
    private Board board ;
    @CreationTimestamp
    private LocalDateTime createdAt;

    @Transient
    private boolean isReplyOwner;

    @Builder
    public Reply(int id, String comment, User user, Board board, LocalDateTime createdAt) {
        this.id = id;
        this.comment = comment;
        this.user = user;
        this.board = board;
        this.createdAt = createdAt;
    }

}

    @Transient
    private boolean isReplyOwner;

    public Board 글상세보기(int boardId, User sessionUser) {
        Board board = boardJPARepository.findByIdJoinUser(boardId)
                .orElseThrow(() -> new Exception404("게시글을 찾을 수 없습니다"));

        boolean isBoardOwner = false;
        if (sessionUser != null) {
            if (sessionUser.getId() == board.getUser().getId()) {
                isBoardOwner = true;
            }
        }

        board.setBoardOwner(isBoardOwner);
        
        board.getReplies().forEach(reply ->{
            boolean isReplyOwner = false ;
            if(sessionUser!=null) {
                if (reply.getUser().getId() == sessionUser.getId()) {
                    isReplyOwner =true;
                }
            }
            reply.setReplyOwner(isReplyOwner);
        });

        return board;
    }

      {{#isReplyOwner}}
            <form action="/reply/{{id}}/delete" method="post">
               <button class="btn">🗑</button>
            </form>
       {{/isReplyOwner}}
       

3. 댓글 삭제하기

    @Transactional
    public int 댓글삭제(Integer replyId,User sessionUser){
        Reply reply = replyJPARepository.findById(replyId).orElseThrow(() -> new Exception404("댓글을 찾을 수 없습니다."));

        int boardId = reply.getBoard().getId(); // 댓글 삭제 전 게시글 번호 남겨놓음

        if(sessionUser.getId()!=reply.getUser().getId()){
            throw new  Exception403("댓글을 삭제할 권한이 없습니다.");
        }
        replyJPARepository.deleteById(replyId);
        return boardId;
    }

    @PostMapping("/reply/{id}/delete")
    public String delete(@PathVariable("id") Integer id){
        User sessionUser = (User) session.getAttribute("sessionUser");
        int boardId = replyService.댓글삭제(id,sessionUser);

        return "redirect:/board/"+boardId ;
    }