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

Gouveia

Do you want to have a single endpoint, and don't mind to have two controller methods? or you want single endpoint and single controller method? – Hughmanick

If there's a way to have 2 controller methods that use the same URI and if spring could choose which method is called based on whether the multipart content is present that would work. – Gouveia

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.

Hughmanick

Awesome solution! I'll also post my solution once I get it finished, checked in, and cleaned up enough to post here. Your solution is better though. – Gouveia

I am unable to get blueimp (with AngularJS) to upload chunked using the first method. It always calls the uploadMultipart (by sending the multipart header). Do you have any special blueimp configuration that you can share as well please? – Underthrust

As far as i remember, nothing fancy. What browser are you using? What headers are sent to the server side? – Hughmanick

Answer 2

Here is the controller for that

package com.faisalbhagat.web.controller;

@Controller
@RequestMapping(value = { "" })
public class UploadController {

    @RequestMapping(value = "/uploadMyFile", method = RequestMethod.POST)
    @ResponseBody
    public String handleFileUpload(MultipartHttpServletRequest request)
            throws Exception {
        Iterator<String> itrator = request.getFileNames();
        MultipartFile multiFile = request.getFile(itrator.next());
                try {
            // just to show that we have actually received the file
            System.out.println("File Length:" + multiFile.getBytes().length);
            System.out.println("File Type:" + multiFile.getContentType());
            String fileName=multiFile.getOriginalFilename();
            System.out.println("File Name:" +fileName);
            String path=request.getServletContext().getRealPath("/");

            //making directories for our required path.
            byte[] bytes = multiFile.getBytes();
            File directory=    new File(path+ "/uploads");
            directory.mkdirs();
            // saving the file
            File file=new File(directory.getAbsolutePath()+System.getProperty("file.separator")+picture.getName());
            BufferedOutputStream stream = new BufferedOutputStream(
                    new FileOutputStream(file));
            stream.write(bytes);
            stream.close();
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            throw new Exception("Error while loading the file");
        }
        return toJson("File Uploaded successfully.")
    }

    public String toJson(Object data)
    {
        ObjectMapper mapper=new ObjectMapper();
        StringBuilder builder=new StringBuilder();
        try {
            builder.append(mapper.writeValueAsString(data));
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return builder.toString();
    }
}

you can find comple solution at with client side code at http://faisalbhagat.blogspot.com/2014/09/springmvc-fileupload-with-ajax-and.html

Rondo

I would advice against using multiFile.getBytes() as it loads entire byte array into memory – Washington