I use Jhipster and this is a controller method:
Controller:
@RequestMapping(value = UPLOAD_URL, method = {RequestMethod.POST},
        headers = {"content-type=multipart/mixed", "content-type=multipart/form-data"},
        consumes = {"multipart/form-data"})
    public ResponseEntity<?> uploadWithMetaData(@RequestPart(value = "file") MultipartFile file,
                                                @RequestPart(value = "documentDTO") DocumentDTO documentDTO,
                                                Locale locale) throws IOException, URISyntaxException, JSONException {
  // business logic
}
Essentially I want to post a file and also a json object.
I my integration test, I can verify that it works as expected:
Integration test:
DocumentDTO documentDTO = getDocumentDTOMockFile();
Long originId = originRepository.findAll().stream().findFirst().get().getId();
documentDTO.setOriginId(originId);
MockMultipartFile jsonFile = new MockMultipartFile("documentDTO", "", "application/json",
jsonUtils.toJson(documentDTO, null).getBytes());
restClientMockMvc
      .perform(MockMvcRequestBuilders.fileUpload("/api/v1/documents/upload")
                .file(fstmp)
                .file(jsonFile))
            .andDo(MockMvcResultHandlers.log())
            .andExpect(status().isOk());
}
Angular frontend:
let fd: FormData = new FormData();
let file = fileForm.files[0];
fd.append("file", file);
let documentDTO = JSON.stringify(document);
fd.append("documentDTO",new Blob([JSON.stringify({
     "documentDTO": documentDTO})], {
         type: "application/json"
    })
);
his.httpClient.post("/api/v1/documents/upload", fd ).subscribe(request => {
   console.log("request", request);
});
I got an interceptor that sets the content-type in the request headers to:
Content-Type:multipart/form-data; boundary=----WebKitFormBoundary4PnIOSOLe5Djj95R
This is how the Request payload looks like:
This is the spring boot log message:
Resolved exception caused by Handler execution: org.springframework.web.multipart.support.MissingServletRequestPartException: Required request part 'file' is not present
This is the response I see in the browser:
{
  "type" : "http://www.jhipster.tech/problem/problem-with-message",
  "title" : "Bad Request",
  "status" : 400,
  "detail" : "Required request part 'file' is not present",
  "path" : "///api/v1/documents/upload",
  "message" : "error.http.400"
}
What I've tried:
- setting content-type to 'Content-Type' : 'multipart/mixed' => result same
 - Creating a pojo with the dto and the file, using @ModelAttribute => same error
 - Then I checked if I got a Multipart Resolver, got it
 
I'm out of ideas, someone any suggestions?
