src/main/java/com/kamco/cd/kamcoback/common/download/DownloadExecutor.java

@@ -0,0 +1,48 @@
+package com.kamco.cd.kamcoback.common.download;
+
+import com.kamco.cd.kamcoback.common.download.dto.DownloadSpec;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Service;
+import org.springframework.web.servlet.mvc.method.annotation.StreamingResponseBody;
+
+@Service
+@RequiredArgsConstructor
+public class DownloadExecutor {
+
+  public ResponseEntity<StreamingResponseBody> stream(DownloadSpec spec) throws IOException {
+
+    if (!Files.isReadable(spec.filePath())) {
+      return ResponseEntity.notFound().build();
+    }
+
+    long fileSize = Files.size(spec.filePath());
+
+    StreamingResponseBody body =
+        os -> {
+          try (InputStream in = Files.newInputStream(spec.filePath())) {
+            in.transferTo(os);
+            os.flush();
+          } catch (Exception e) {
+            // 고용량은 중간 끊김 흔하니까 throw 금지
+          }
+        };
+
+    String fileName =
+        spec.downloadName() != null
+            ? spec.downloadName()
+            : spec.filePath().getFileName().toString();
+
+    return ResponseEntity.ok()
+        .contentType(
+            spec.contentType() != null ? spec.contentType() : MediaType.APPLICATION_OCTET_STREAM)
+        .contentLength(fileSize)
+        .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + fileName + "\"")
+        .body(body);
+  }
+}

src/main/java/com/kamco/cd/kamcoback/common/download/dto/DownloadSpec.java

@@ -0,0 +1,12 @@
+package com.kamco.cd.kamcoback.common.download.dto;
+
+import java.nio.file.Path;
+import java.util.UUID;
+import org.springframework.http.MediaType;
+
+public record DownloadSpec(
+    UUID uuid, // 다운로드 식별(로그/정책용)
+    Path filePath, // 실제 파일 경로
+    String downloadName, // 사용자에게 보일 파일명
+    MediaType contentType // 보통 OCTET_STREAM
+    ) {}

src/main/java/com/kamco/cd/kamcoback/label/LabelAllocateApiController.java

@@ -1,5 +1,7 @@
 package com.kamco.cd.kamcoback.label;
 
+import com.kamco.cd.kamcoback.common.download.DownloadExecutor;
+import com.kamco.cd.kamcoback.common.download.dto.DownloadSpec;
 import com.kamco.cd.kamcoback.config.api.ApiResponseDto;
 import com.kamco.cd.kamcoback.label.dto.LabelAllocateDto;
 import com.kamco.cd.kamcoback.label.dto.LabelAllocateDto.InferenceDetail;
@@ -23,17 +25,15 @@ import io.swagger.v3.oas.annotations.responses.ApiResponses;
 import io.swagger.v3.oas.annotations.tags.Tag;
 import jakarta.validation.Valid;
 import java.io.IOException;
-import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.List;
 import java.util.UUID;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.apache.coyote.BadRequestException;
 import org.springframework.beans.factory.annotation.Value;
-import org.springframework.core.io.Resource;
 import org.springframework.data.domain.Page;
-import org.springframework.http.HttpHeaders;
 import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.GetMapping;
@@ -43,6 +43,7 @@ import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.servlet.mvc.method.annotation.StreamingResponseBody;
 
 @Slf4j
 @Tag(name = "라벨링 작업 관리", description = "라벨링 작업 배정 및 통계 조회 API")
@@ -52,6 +53,7 @@ import org.springframework.web.bind.annotation.RestController;
 public class LabelAllocateApiController {
 
   private final LabelAllocateService labelAllocateService;
+  private final DownloadExecutor downloadExecutor;
 
   @Value("${file.dataset-response}")
   private String responsePath;
@@ -380,25 +382,19 @@ public class LabelAllocateApiController {
         @ApiResponse(responseCode = "500", description = "서버 오류", content = @Content)
       })
   @GetMapping("/download/{uuid}")
-  public ResponseEntity<Resource> download(
+  public ResponseEntity<StreamingResponseBody> download(
       @Parameter(example = "6d8d49dc-0c9d-4124-adc7-b9ca610cc394") @PathVariable UUID uuid)
       throws IOException {
-    //
-    //    if (!labelAllocateService.isDownloadable(uuid)) {
-    //      throw new BadRequestException();
-    //    }
+
+    if (!labelAllocateService.isDownloadable(uuid)) {
+      throw new BadRequestException();
+    }
+
     String uid = labelAllocateService.findLearnUid(uuid);
     Path zipPath = Paths.get(responsePath).resolve(uid + ".zip");
-    long size = Files.size(zipPath);
-    Resource resource = new org.springframework.core.io.UrlResource(zipPath.toUri());
 
-    return ResponseEntity.ok()
-        .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + uid + ".zip" + "\"")
-        .header(HttpHeaders.ACCEPT_RANGES, "bytes")
-        .header("X-Accel-Buffering", "no") // nginx/ingress 버퍼링 방지 힌트
-        .contentType(MediaType.APPLICATION_OCTET_STREAM)
-        .contentLength(size)
-        .body(resource);
+    return downloadExecutor.stream(
+        new DownloadSpec(uuid, zipPath, uid + ".zip", MediaType.APPLICATION_OCTET_STREAM));
   }
 
   @Operation(summary = "라벨 파일 다운로드 이력 조회", description = "라벨 파일 다운로드 이력 조회")

src/main/resources/static/download_progress_test.html

@@ -9,6 +9,12 @@
 
 UUID:
 <input id="uuid" value="6d8d49dc-0c9d-4124-adc7-b9ca610cc394" />
+<br><br>
+
+JWT Token:
+<input id="token" style="width:600px;" placeholder="Bearer 토큰 붙여넣기" />
+<br><br>
+
 <button onclick="download()">다운로드</button>
 
 <br><br>
@@ -18,11 +24,25 @@ UUID:
 <script>
   async function download() {
     const uuid = document.getElementById("uuid").value.trim();
+    const token = document.getElementById("token").value.trim();
+
+    if (!uuid) {
+      alert("UUID 입력하세요");
+      return;
+    }
+
+    if (!token) {
+      alert("토큰 입력하세요");
+      return;
+    }
+
     const url = `/api/training-data/stage/download/${uuid}`;
 
     const res = await fetch(url, {
       headers: {
-        "Authorization": `Bearer eyJhbGciOiJIUzM4NCJ9.eyJzdWIiOiJmYzUwNDYxZC0wOGYwLTRhYjYtOTg4MC03ZmJmYzM2ZjNmOGIiLCJpYXQiOjE3NzA3Nzg3ODIsImV4cCI6MTc3MDg2NTE4Mn0.4OOF4r2lxymr8UwpqRW_qLecE8IpwNOFJHXSsZX6d6Yuk2fT7NcYPS5LenFRli3N`,
+        "Authorization": token.startsWith("Bearer ")
+          ? token
+          : `Bearer ${token}`,
         "kamco-download-uuid": uuid
       }
     });