下载从Spring Boot Server生成的角度的PDF

Question

我正在努力从用户界面下载一个pdf文件（角），从Spring Boot生成。我可以用相同的API从浏览器下载pdf文件。

非常感谢快速的帮助。

SyntaxError：XMLHttpRequest.onload消息：“JSON at position 0”Stack：“SyntaxError：JSON at position 0 at JSON.Parse（）at XMLHttpRequest.onload（http://localhost:4200/vendor.js:19662:51)

@RequestMapping(value = "/downloadPDF/", method = RequestMethod.GET, produces = "application/pdf")
    public ResponseEntity<Resource> downloadServicePack(@RequestHeader("Authorization") String token,
            HttpServletRequest request) throws WorkflowException, Exception {

        String fileName = "TWEVL_ServiceDesignPack.pdf";

        // String fileName ="ServiceDesignPdf.pdf";
        Resource resource = fileStorageService.loadFileAsResource(fileName);

        // Try to determine file's content type
        String contentType = null;
        try {
            contentType = request.getServletContext().getMimeType(resource.getFile().getAbsolutePath());
        } catch (IOException ex) {
            // logger.info("Could not determine file type.");
        }

        // Fallback to the default content type if type could not be determined
        if (contentType == null) {
            contentType = "application/octet-stream";
        }

        return ResponseEntity.ok().contentType(MediaType.parseMediaType(contentType))
                .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + resource.getFilename() + "\"")
                .body(resource);

    }

@Service
public class FileStorageService {

    private final Path fileStorageLocation;

    @Autowired
    public FileStorageService(FileStorageProperties fileStorageProperties) throws Exception {
        this.fileStorageLocation = Paths.get(fileStorageProperties.getUploadDir())
                .toAbsolutePath().normalize();

        try {
            Files.createDirectories(this.fileStorageLocation);
        } catch (Exception ex) {
            throw new Exception("Could not create the directory where the uploaded files will be stored.", ex);
        }
    }

    
    public Resource loadFileAsResource(String fileName) throws Exception {
        try {
            Path filePath = this.fileStorageLocation.resolve(fileName).normalize();
            Resource resource = new UrlResource(filePath.toUri());
            if(resource.exists()) {
                return resource;
            } else {
                throw new Exception("File not found " + fileName);
            }
        } catch (Exception ex) {
            throw new Exception("File not found " + fileName, ex);
        }
    }
}

 @Injectable()
    export class JwtInterceptor implements HttpInterceptor {
      constructor(private authenticationService: AuthenticationService) {}
    
      intercept(
        request: HttpRequest<any>,
        next: HttpHandler
      ): Observable<HttpEvent<any>> {
        // add authorization header with jwt token if available
        const token = this.authenticationService.currentUserValue;
            request = request.clone({
              setHeaders: {
                Authorization: `Bearer ${token.token}`,
                Accept: `application/pdf`,
                responseType:'blob',
                'Content-Type':`application/pdf`
              }
            });
        return next.handle(request);
      }
    }

  downloadServicePackPDF() {
    this.tcmtSrv
      .downloadServicePack()
      .subscribe(
        (blob: Blob)  => {
          console.log('report is downloaded');
       
        },
        (error) => {
          console.log(error);
         }
      );
  }

   downloadServicePack() {
   //header is being passed from interceptor
    return this.apiSrv.get(DOWNLOAD_SERVICE_PACK,'');
  }

Answer 1

我没有在拦截器中传递responseType。我试图向它传递服务ts，但拦截器正在重写这些头&服务级别上给出的其他参数。

在拦截器中像下面这样传递头部&它起作用了-

const newRequest = request.clone({ setHeaders: { Authorization: Bearer ${token.token}, "Content-Type": "text/plain", Accept: "text/plain" },responseType: "text", });