Spring - RestTemplate - 多部分文件

Question

这个控制器工作正常

@Controller
public class FileUploadController {
....
@PostMapping("/convert")
public void fileUpload(@RequestParam("file") MultipartFile file, 
     RedirectAttributes redirectAttributes, HttpServletResponse response) {

现在我想通过 RestTemplate 从另一个 spring 项目调用这个控制器。我尝试了很多东西，但注意工作。这是我最后的代码：

@Controller
public class FileController {
....
@PostMapping("/convert")
public void fileUpload(@RequestParam("file") MultipartFile file, RedirectAttributes redirectAttributes,
        HttpServletResponse response) throws Exception {


    ArrayList<HttpMessageConverter<?>> converters = new ArrayList<HttpMessageConverter<?>>(
            Arrays.asList(new FormHttpMessageConverter(),new MappingJackson2HttpMessageConverter(), new ResourceHttpMessageConverter()));

    RestTemplate template = restTemplate();

    template.setMessageConverters(converters);

    HttpHeaders header = new HttpHeaders();
    header.setContentType(MediaType.MULTIPART_FORM_DATA);

    MultiValueMap<String, Object> multipartRequest = new LinkedMultiValueMap<>();
    multipartRequest.add("file", file);

    HttpEntity<MultiValueMap<String, Object>> requestEntity = new HttpEntity<>(multipartRequest, header);

    template.postForObject("http://localhost:8080/convert", requestEntity, String.class);

}

我如果调用 FileUploadController（通过邮递员）它就可以工作。如果调用 FileController 我得到这个异常

"exception": 
"org.springframework.http.converter.HttpMessageNotWritableException",
"message": "Could not write request: no suitable HttpMessageConverter found for request type [org.springframework.web.multipart.support.StandardMultipartHttpServletRequest$StandardMultipartFile]",
"path": "/convert"

Answer 1

看看这里的答案，它应该正是您要找的：尝试使用多部分文件测试休息服务

问题是关于使用RestTemplate.

基本上，您要做的是模拟文件上传。你可以尝试这样的事情：

MultiValueMap<String, Object> parameters = new LinkedMultiValueMap<String, Object>();
parameters.add("file", new FileSystemResource("file.jpg"));

HttpHeaders headers = new HttpHeaders();
headers.set("Content-Type", "multipart/form-data");
headers.set("Accept", "text/plain");

String result = restTemplate.postForObject(
    "http://host:port/path", 
    new HttpEntity<MultiValueMap<String, Object>>(parameters, headers), 
    String.class);