如何使用 Spring REST multipart 分块发送大文件（REST 客户端）

Question

我正在使用 spring REST 编写一个将文件上传到数据库的客户端。以下是我无法更改的服务器端控制器代码：

@RequestMapping(method = RequestMethod.POST)
public ResponseEntity<UploadResponseDto> uploadFile(@RequestParam("file") MultipartFile file) throws IOException {

    String contentType =  file.getContentType();
    if ( contentType == null || !contentType.equalsIgnoreCase(APPLICATION_OCTET_STREAM)) {
        contentType = APPLICATION_OCTET_STREAM;
    }
    GridFSFile gridFSFile = gridFsTemplate.store(file.getInputStream(), file.getOriginalFilename(), contentType);

    MultiValueMap<String, String> headers = new LinkedMultiValueMap<>();
    String fileLocation = linkTo(FileAttachmentController.class).slash(gridFSFile.getId()).toUri().toString();
    headers.add(LOCATION, fileLocation);
    UploadResponseDto uploadResponseDto = new UploadResponseDto(file.getOriginalFilename(), fileLocation);
    return new ResponseEntity<>(uploadResponseDto, headers, HttpStatus.CREATED);
}

我发送文件的客户端代码是：

SimpleClientHttpRequestFactory factory = new SimpleClientHttpRequestFactory();
    factory.setBufferRequestBody(false);
    RestTemplate restTemplate = new RestTemplate(factory);

    HttpHeaders headers = new HttpHeaders();
    headers.set(HttpHeaders.AUTHORIZATION, "Bearer " + token);
    headers.set("Accept", "application/json");
    headers.setContentType(MediaType.MULTIPART_FORM_DATA);

    File file = new File(fileToUpload);
    MultiValueMap<String, Object> data = new LinkedMultiValueMap<String, Object>();
    ByteArrayResource resource = new ByteArrayResource(
        Files.readAllBytes(Paths.get(fileToUpload))) {
        @Override
        public String getFilename() {
            return file.getName();
        }
    };
    data.add("file", resource);
    HttpEntity<MultiValueMap<String, Object>> requestEntity = new HttpEntity<MultiValueMap<String, Object>>(
        data, headers);
    ResponseEntity<Map> apiResponse = null;

    apiResponse = restTemplate.exchange(
        "http://{end_point_url}",
        HttpMethod.POST, requestEntity, Map.class);

但是当我使用此代码发送 50 MB 文件时，它会抛出“413 请求实体太大错误”

有人可以帮我解决如何分块发送大文件吗？

感谢和问候， Vikas Gite

Answer 1

您可以使用指定上传文件的大小

org.springframework.web.multipart.commons.CommonsMultipartResolver

@Bean(name = "multipartResolver")
public CommonsMultipartResolver multipartResolver() {
    CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver();
    multipartResolver.setMaxUploadSize(54525952); //...specify your size of file  (20971520 - 20 MB) (54525952 - 52 MB)
    return multipartResolver;
}