[Spring] RequestDTO, ResponseDTO

공모전을 준비하며 어깨 너머 배운 것들을 정리해보았습니다.

요청으로부터 정보를 받아서 DB 저장할 때

• NFTAddRequestDTO
  • 컨트롤러에서 @Valid하고, requestDTO에서 필수 값 지정할 수 있음
  • toEntity()로 DB에 저장

@Getter
@AllArgsConstructor
public class NFTAddRequestDTO {

    @NotBlank
    private String assetContractAddress;
    
    @NotBlank
    private String tokenId;

    public NFT toEntity() {
        return new NFT(assetContractAddress, tokenId);
    }
}

• NFT
  • NFT 엔티티에서 @AllArgsConstructor 를 하지 않고 생성자를 직접 만든 이유 : @AllArgsConstructor 어노테이션을 하면 id 값도 파라미터로 만들어줘야 하기 때문임
  • RequestDTO에서 nft 객체가 오면, 생성자를 통해 저장

@Entity
@Getter
@NoArgsConstructor
public class NFT extends DateTimeEntity {

    @Id
    @GeneratedValue
    @Column(name = "nft_id")
    private Long id;

    private String assetContractAddress;
    private String tokenId;

    public NFT(String assetContractAddress, String tokenId) {
        this.assetContractAddress = assetContractAddress;
        this.tokenId = tokenId;
    }
}

• 이용 - Controller
  • NFT nft = requestDTO.toEntity();

@RestController
@RequiredArgsConstructor
@RequestMapping("drawing")
@Api(tags = "🖼 그림 API")
public class DrawingController {

    private final DrawingService drawingService;

    ...

    @PutMapping("{drawingId}/nft")
    @ApiOperation(value = "NFT 정보 넣기", notes = "본인 그림에만 가능")
    @ResponseStatus(NO_CONTENT)
    public DrawingResponseDTO addNft(@AuthDTO AuthMemberDTO memberDTO, @PathVariable Long drawingId,
                                     @Valid @RequestBody NFTAddRequestDTO requestDTO) {
        Member member = memberService.getMember(memberDTO.getId());
        NFT nft = requestDTO.toEntity();
        return drawingService.putNft(member, drawingId, nft);
    }
}

---

응답할 때

• from 이라고 함수 짓기

@Getter
@AllArgsConstructor
public class NFTResponseDTO {

    private final String assetContractAddress;
    private final String tokenId;

public static NFTResponseDTO from(NFT nft) {
        return new NFTResponseDTO(nft.getAssetContractAddress(), nft.getTokenId());
    }
}

• 이용 - Service

@Service
@RequiredArgsConstructor
public class DrawingService {
 
    ...
 
    @Transactional
    public DrawingResponseDTO putNft(Member member, Long drawingId, NFT nft) {
        Drawing drawing = getDrawingById(drawingId);
        validateDrawingOwner(member, drawing);
        NFT savedNFT = nftRepository.save(nft);
        drawing.putNftInfo(savedNFT);
        return DrawingResponseDTO.from(drawing);
    }

    public void validateDrawingOwner(Member member, Drawing drawing) {
        if (!drawing.ownerEquals(member))
            throw new DrawingOwnerException();  // custom excetption
    }
}
    

• 변수가 많을 경우 builder를 생성하면 좋음
• MemeberResponseDTO

@Getter
@AllArgsConstructor
@Builder(access = PRIVATE)
public class MemberResponseDTO {

    private final Long id;
    private final String name;
    private final String profileImage;
    private final String accountEmail;

    public static MemberResponseDTO from(Member member) {
        return MemberResponseDTO.builder()
                .id(member.getId())
                .name(member.getName())
                .accountEmail(member.getAccountEmail())
                .profileImage(member.getProfileImage())
                .build();
    }
}

• DrawingResponseDTO

@Getter
@AllArgsConstructor(access = AccessLevel.PRIVATE)
@Builder(access = AccessLevel.PRIVATE)
public class DrawingResponseDTO {

    private final Long id;
    private final String title;
    private final String description;
    private final String fileName;
    @JsonFormat(
            shape = JsonFormat.Shape.STRING,
            pattern = "yyyy-MM-dd HH:mm:ss",
            locale = "Asia/Seoul"
    )
    private final LocalDateTime createdAt;
    private final MemberResponseDTO member;
    private final Set<TagResponseDTO> tags;
    private final Integer heartCount;
    private final Integer scrapCount;
    private NFTResponseDTO nft;

    public static DrawingResponseDTO from(Drawing drawing) {
        Set<TagResponseDTO> tags = drawing.getTags()
                .stream()
                .map(TagResponseDTO::from)
                .collect(Collectors.toSet());
        NFTResponseDTO nft = NFTResponseDTO.from(drawing.getNft());
        MemberResponseDTO member = MemberResponseDTO.from(drawing.getMember());

        return DrawingResponseDTO.builder()
                .id(drawing.getId())
                .title(drawing.getTitle())
                .description(drawing.getDescription())
                .fileName(drawing.getImage().getFileName())
                .createdAt(drawing.getCreatedAt())
                .member(member)
                .tags(tags)
                .heartCount(drawing.getHeartCount())
                .scrapCount(drawing.getScrapCount())
                .nft(nft)
                .build();
    }
}