Multipart File upload Spring Boot

2019-01-08 12:37发布

问题:

Im using Spring Boot and want to use a Controller to receive a multipart file upload. When sending the file I keep getting the error 415 unsupported content type response and the controller is never reached

There was an unexpected error (type=Unsupported Media Type, status=415).
Content type 'multipart/form-data;boundary=----WebKitFormBoundary1KvzQ1rt2V1BBbb8' not supported

Ive tried sending using form:action in html/jsp page and also in a standalone client application which uses RestTemplate. All attempts give the same result

multipart/form-data;boundary=XXXXX not supported.

It seems from multipart documentation that the boundary param has to be added to the multipart upload however this seems to not match the controller receiving "multipart/form-data"

My controller method is setup as follows

@RequestMapping(value = "/things", method = RequestMethod.POST, consumes = "multipart/form-data" ,
                                     produces = { "application/json", "application/xml" })
     public ResponseEntity<ThingRepresentation> submitThing(HttpServletRequest request,
                                     @PathVariable("domain") String domainParam,
                                     @RequestParam(value = "type") String thingTypeParam,
                                     @RequestBody MultipartFile[] submissions) throws Exception

With Bean Setup

 @Bean
 public MultipartConfigElement multipartConfigElement() {
     return new MultipartConfigElement("");
 }

 @Bean
 public MultipartResolver multipartResolver() {
     org.springframework.web.multipart.commons.CommonsMultipartResolver multipartResolver = new org.springframework.web.multipart.commons.CommonsMultipartResolver();
     multipartResolver.setMaxUploadSize(1000000);
     return multipartResolver;
 }

As you can see I've set the consumes type to "multipart/form-data" but when the multipart is sent it must have a boundary parameter and places a random boundary string.

Can anyone please tell me how I can either set the content type in controller to match or change my request to match my controller setup?

My attempts to send ... Attempt 1...

<html lang="en">
<body>

    <br>
    <h2>Upload New File to this Bucket</h2>
    <form action="http://localhost:8280/appname/domains/abc/things?type=abcdef00-1111-4b38-8026-315b13dc8706" method="post" enctype="multipart/form-data">
        <table width="60%" border="1" cellspacing="0">
            <tr>
                <td width="35%"><strong>File to upload</strong></td>
                <td width="65%"><input type="file" name="file" /></td>
            </tr>
            <tr>
                <td>&nbsp;</td>
                <td><input type="submit" name="submit" value="Add" /></td>
            </tr>
        </table>
    </form>
</body>
</html>

Attempt 2....

RestTemplate template = new RestTemplate();
MultiValueMap<String, Object> parts = new LinkedMultiValueMap<String, Object>();
parts.add("file", new FileSystemResource(pathToFile));

try{

    URI response = template.postForLocation(url, parts);
}catch(HttpClientErrorException e){
    System.out.println(e.getResponseBodyAsString());
}

Attempt 3...

FormHttpMessageConverter formHttpMessageConverter = new FormHttpMessageConverter();
        formHttpMessageConverter.setCharset(Charset.forName("UTF8"));


        RestTemplate restTemplate = new RestTemplate();

        restTemplate.getMessageConverters().add( formHttpMessageConverter );
        restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());
        restTemplate.setRequestFactory(new HttpComponentsClientHttpRequestFactory());

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

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

        HttpEntity<MultiValueMap<String, Object>> imageEntity = new HttpEntity<MultiValueMap<String, Object>>(map, imageHeaders);
        ResponseEntity e=  restTemplate.exchange(uri, HttpMethod.POST, imageEntity, Boolean.class);
        System.out.println(e.toString());

回答1:

@RequestBody MultipartFile[] submissions

should be

@RequestParam("file") MultipartFile[] submissions

The files are not the request body, they are part of it and there is no built-in HttpMessageConverter that can convert the request to an array of MultiPartFile.

You can also replace HttpServletRequest with MultipartHttpServletRequest, which gives you access to the headers of the individual parts.



回答2:

You can simply use a controller method like this:

@RequestMapping(value = "/uploadFile", method = RequestMethod.POST)
@ResponseBody
public ResponseEntity<?> uploadFile(
    @RequestParam("file") MultipartFile file) {

  try {
    // Handle the received file here
    // ...
  }
  catch (Exception e) {
    return new ResponseEntity<>(HttpStatus.BAD_REQUEST);
  }

  return new ResponseEntity<>(HttpStatus.OK);
} // method uploadFile

Without any additional configurations for Spring Boot.

Using the following html form client side:

<html>
<body>
  <form action="/uploadFile" method="POST" enctype="multipart/form-data">
    <input type="file" name="file">
    <input type="submit" value="Upload"> 
  </form>
</body>
</html>

If you want to set limits on files size you can do it in the application.properties:

# File size limit
multipart.maxFileSize = 3Mb

# Total request size for a multipart/form-data
multipart.maxRequestSize = 20Mb

Moreover to send the file with Ajax take a look here: http://blog.netgloo.com/2015/02/08/spring-boot-file-upload-with-ajax/



回答3:

Latest version of SpringBoot makes uploading multiple files very easy also. On the browser side you just need the standard HTML upload form, but with multiple input elements (one per file to upload, which is very important), all having the same element name (name="files" for the example below)

Then in your Spring @Controller class on the server all you need is something like this:

@RequestMapping(value = "/upload", method = RequestMethod.POST)
    public @ResponseBody ResponseEntity<?> upload(
        @RequestParam("files") MultipartFile[] uploadFiles) throws Exception     
{
    ...now loop over all uploadFiles in the array and do what you want
  return new ResponseEntity<>(HttpStatus.OK);
}

Those are the tricky parts. That is, knowing to create multiple input elements each named "files", and knowing to use a MultipartFile[] (array) as the request parameter are the tricky things to know, but it's just that simple. I won't get into how to process a MultipartFile entry, because there's plenty of docs on that already.



回答4:

   @Bean
    MultipartConfigElement multipartConfigElement() {
        MultipartConfigFactory factory = new MultipartConfigFactory();
        factory.setMaxFileSize("5120MB");
        factory.setMaxRequestSize("5120MB");
        return factory.createMultipartConfig();
    }

put it in class where you are defining beans



回答5:

@RequestMapping(value="/add/image", method=RequestMethod.POST)
public ResponseEntity upload(@RequestParam("id") Long id, HttpServletResponse response, HttpServletRequest request)
{   
    try {
        MultipartHttpServletRequest multipartRequest=(MultipartHttpServletRequest)request;
        Iterator<String> it=multipartRequest.getFileNames();
        MultipartFile multipart=multipartRequest.getFile(it.next());
        String fileName=id+".png";
        String imageName = fileName;

        byte[] bytes=multipart.getBytes();
        BufferedOutputStream stream= new BufferedOutputStream(new FileOutputStream("src/main/resources/static/image/book/"+fileName));;

        stream.write(bytes);
        stream.close();
        return new ResponseEntity("upload success", HttpStatus.OK);

    } catch (Exception e) {
        e.printStackTrace();
        return new ResponseEntity("Upload fialed", HttpStatus.BAD_REQUEST);
    }   
}


回答6:

In Controller, your method should be;

@RequestMapping(value = "/upload", method = RequestMethod.POST)
    public ResponseEntity<SaveResponse> uploadAttachment(@RequestParam("file") MultipartFile file, HttpServletRequest request) {
....

Further, you need to update application.yml (or application.properties) to support maximum file size and request size.

spring:
    http:
        multipart:
            max-file-size: 5MB
            max-request-size: 20MB