refactor: 응답 객체 추가 및 반환요청 수정

Author: dohy-eon

src/main/java/dmu/dasom/api/domain/news/service/NewsService.java

@@ -1,5 +1,6 @@
 package dmu.dasom.api.domain.news.service;
 
+import dmu.dasom.api.global.file.dto.FileResponseDto;
 import dmu.dasom.api.global.file.entity.FileEntity;
 import dmu.dasom.api.global.file.service.FileService;
 import dmu.dasom.api.domain.common.exception.CustomException;
@@ -52,7 +53,7 @@ public NewsResponseDto getNewsById(Long id) {
     // 뉴스 생성
     @Transactional
     public NewsResponseDto createNews(NewsRequestDto requestDto) {
-        List<FileEntity> uploadedFiles = fileService.getFilesByIds(requestDto.getFileIds());
+        List<FileResponseDto> uploadedFiles = fileService.getFilesByIds(requestDto.getFileIds());
 
         List<String> base64Images = uploadedFiles.stream()
                 .map(file -> "data:" + file.getFileType() + ";base64," + file.getBase64Data())
@@ -73,7 +74,8 @@ public NewsResponseDto updateNews(Long id, NewsRequestDto requestDto) {
         NewsEntity news = newsRepository.findById(id)
                 .orElseThrow(() -> new CustomException(ErrorCode.NOT_FOUND));
 
-        List<FileEntity> uploadedFiles = fileService.getFilesByIds(requestDto.getFileIds());
+        // fileEntity -> response로 수정
+        List<FileResponseDto> uploadedFiles = fileService.getFilesByIds(requestDto.getFileIds());
 
         List<String> base64Images = uploadedFiles.stream()
                 .map(file -> "data:" + file.getFileType() + ";base64," + file.getBase64Data())

src/main/java/dmu/dasom/api/global/file/controller/FileController.java

@@ -1,5 +1,6 @@
 package dmu.dasom.api.global.file.controller;
 
+import dmu.dasom.api.global.file.dto.FileResponseDto;
 import dmu.dasom.api.global.file.service.FileService;
 import lombok.RequiredArgsConstructor;
 import org.springframework.http.ResponseEntity;
@@ -15,17 +16,21 @@ public class FileController {
 
     private final FileService fileService;
 
-    // 파일 업로드
     @PostMapping("/upload")
     public ResponseEntity<List<Long>> uploadFiles(@RequestParam("files") List<MultipartFile> files) {
         List<Long> fileIds = fileService.uploadFiles(files);
         return ResponseEntity.ok(fileIds);
     }
 
-    // 파일 조회
+    // dto 반환으로 수정
     @GetMapping("/{fileId}")
-    public ResponseEntity<String> getFile(@PathVariable Long fileId) {
-        return ResponseEntity.ok(fileService.getFileBase64(fileId));
+    public ResponseEntity<FileResponseDto> getFile(@PathVariable Long fileId) {
+        return ResponseEntity.ok(fileService.getFileById(fileId));
+    }
+
+    @GetMapping("/list")
+    public ResponseEntity<List<FileResponseDto>> getFiles(@RequestParam List<Long> fileIds) {
+        return ResponseEntity.ok(fileService.getFilesByIds(fileIds));
     }
 
 }

src/main/java/dmu/dasom/api/global/file/dto/FileResponseDto.java

@@ -0,0 +1,16 @@
+package dmu.dasom.api.global.file.dto;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@Data
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+public class FileResponseDto {
+    private Long id;
+    private String fileType;
+    private String base64Data;   // Base64 인코딩 데이터
+}

src/main/java/dmu/dasom/api/global/file/service/FileService.java

@@ -1,5 +1,6 @@
 package dmu.dasom.api.global.file.service;
 
+import dmu.dasom.api.global.file.dto.FileResponseDto;
 import dmu.dasom.api.global.file.entity.FileEntity;
 import dmu.dasom.api.global.file.repository.FileRepository;
 import lombok.RequiredArgsConstructor;
@@ -33,20 +34,35 @@ public List<Long> uploadFiles(List<MultipartFile> files) {
             }
         }).collect(Collectors.toList());
 
-        return fileRepository.saveAll(savedFiles).stream().map(FileEntity::getId).collect(Collectors.toList());
+        return fileRepository.saveAll(savedFiles)
+                .stream()
+                .map(FileEntity::getId)
+                .collect(Collectors.toList());
     }
 
     // 파일 하나 조회
-    public String getFileBase64(Long fileId) {
+    public FileResponseDto getFileById(Long fileId) {
         FileEntity file = fileRepository.findById(fileId)
                 .orElseThrow(() -> new RuntimeException("파일을 찾을 수 없음"));
 
-        return "data:" + file.getFileType() + ";base64," + file.getBase64Data();
+        return convertToDto(file);
     }
 
     // 파일 여러개 조회
-    public List<FileEntity> getFilesByIds(List<Long> fileIds) {
-        return fileRepository.findAllById(fileIds);
+    public List<FileResponseDto> getFilesByIds(List<Long> fileIds) {
+        List<FileEntity> files = fileRepository.findAllById(fileIds);
+        return files.stream()
+                .map(this::convertToDto)
+                .collect(Collectors.toList());
     }
-    
+
+    // FileEntity → FileResponseDto 변환용
+    private FileResponseDto convertToDto(FileEntity file) {
+        return FileResponseDto.builder()
+                .id(file.getId())
+                .fileType(file.getFileType())
+                .base64Data("data:" + file.getFileType() + ";base64," + file.getBase64Data())
+                .build();
+    }
+
 }