How do I receive a file upload in spring mvc using both multipart/form and chunked encoding?

Question

I am trying to write a spring mvc method that can receive either a multipart/form or transfer-encoding chunked file upload. I can write a separate method to handle each type but I'd like to do it with the same method so i can use the same REST POST uri such as:

http://host:8084/attachments/testupload

Here is my best attempt so far:

@RequestMapping(value = { "/testupload" }, method = RequestMethod.POST, produces = 
  "application/json")
public @ResponseBody
ResponseEntity<MessageResponseModel> testUpload(
  @RequestParam(value = "filedata", required = false) MultipartFile filedata,
  final HttpServletRequest request) throws IOException {

  InputStream is = null;
  if (filedata == null) {
    is = request.getInputStream();
  }
  else {
    is = filedata.getInputStream();
  }
  byte[] bytes = IOUtils.toByteArray(is);
  System.out.println("read " + bytes.length + " bytes.");

  return new ResponseEntity<MessageResponseModel>(null, null, HttpStatus.OK);
}

Using the above method I can upload a multipart file, but if i upload a chunked file I get an exception from spring that says:

org.springframework.web.multipart.MultipartException: \
The current request is not a multipart request

If I remove the MultipartFile request param it works great for transfer encoding chunked. If I leave it in it works great for MultipartFile uploads. How can I do it with the same method to handle both upload types?

This works fine for chunked:

@RequestMapping(value = { "/testupload" }, method = RequestMethod.POST, produces = 
  "application/json")
public @ResponseBody
ResponseEntity<MessageResponseModel> testUpload(
  final HttpServletRequest request) throws IOException {

  InputStream is = null;
  is = request.getInputStream();
  byte[] bytes = IOUtils.toByteArray(is);
  System.out.println("read " + bytes.length + " bytes.");

  return new ResponseEntity<MessageResponseModel>(null, null, HttpStatus.OK);
}

and this works great for MultipartFile:

@RequestMapping(value = { "/testupload" }, method = RequestMethod.POST, produces = 
  "application/json")
public @ResponseBody
ResponseEntity<MessageResponseModel> testUpload(
  @RequestParam MultipartFile filedata) throws IOException {

  InputStream is = null;
  is = filedata.getInputStream();
  byte[] bytes = IOUtils.toByteArray(is);
  System.out.println("read " + bytes.length + " bytes.");

  return new ResponseEntity<MessageResponseModel>(null, null, HttpStatus.OK);
}

It should be possible, does anybody know how to do this?

Thank you, Steve

Answer 1

Excerpt from my code (Spring 3.2, blueimp file upload with AngularJS):

/**
 * Handles chunked file upload, when file exceeds defined chunked size.
 * 
 * This method is also called by modern browsers and IE >= 10
 */
@RequestMapping(value = "/content-files/upload/", method = RequestMethod.POST, headers = "content-type!=multipart/form-data")
@ResponseBody
public UploadedFile uploadChunked(
        final HttpServletRequest request,
        final HttpServletResponse response) {

    request.getHeader("content-range");//Content-Range:bytes 737280-819199/845769
    request.getHeader("content-length"); //845769
    request.getHeader("content-disposition"); // Content-Disposition:attachment; filename="Screenshot%20from%202012-12-19%2017:28:01.png"
    request.getInputStream(); //actual content.

    //Regex for content range: Pattern.compile("bytes ([0-9]+)-([0-9]+)/([0-9]+)");
    //Regex for filename: Pattern.compile("(?<=filename=\").*?(?=\")");

    //return whatever you want to json
    return new UploadedFile();
}

/**
 * Default Multipart file upload. This method should be invoked only by those that do not
 * support chunked upload.
 * 
 * If browser supports chunked upload, and file is smaller than chunk, it will invoke
 * uploadChunked() method instead.
 * 
 * This is instead a fallback method for IE <=9
 */
@RequestMapping(value = "/content-files/upload/", method = RequestMethod.POST, headers = "content-type=multipart/form-data")
@ResponseBody
public HttpEntity<UploadedFile> uploadMultipart(
        final HttpServletRequest request,
        final HttpServletResponse response,
        @RequestParam("file") final MultipartFile multiPart) {

    //handle regular MultipartFile

    // IE <=9 offers to save file, if it is returned as json, so set content type to plain.
    HttpHeaders headers = new HttpHeaders();
    headers.setContentType(MediaType.TEXT_PLAIN);
    return new HttpEntity<>(new UploadedFile(), headers);
}

This should get you started. Minimal testing done on IE8, IE9, IE10, Chrome, FF. Of course there might be issues, and probably there is an easier way of extracting content ranges, but .. works for me.