Question

我正在开发基于Spring 3.2的RESTful服务。我正面临一个控制器处理混合多部分HTTP请求的问题，第二部分使用XML或JSON格式化数据，第二部分使用图像文件。

@RequestMapping(value = "/User/Image", method = RequestMethod.POST,  consumes = {"multipart/mixed"},produces="applcation/json")

public
ResponseEntity<List<Map<String, String>>> createUser(
        @RequestPart("file") MultipartFile file, @RequestPart(required=false) User user) {

    System.out.println("file" + file);

    System.out.println("user " + user);

    System.out.println("received file with original filename: "
            + file.getOriginalFilename());

    // List<MultipartFile> files = uploadForm.getFiles();
    List<Map<String, String>> response = new ArrayList<Map<String, String>>();
    Map<String, String> responseMap = new HashMap<String, String>();

    List<String> fileNames = new ArrayList<String>();

    if (null != file) {
        // for (MultipartFile multipartFile : files) {

        String fileName = file.getOriginalFilename();
        fileNames.add(fileName);

        try {
            file.transferTo(new File("C:/" + file.getOriginalFilename()));
        } catch (IllegalStateException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    responseMap.put("displayText", file.getOriginalFilename());
    responseMap.put("fileSize", "" + file.getSize());
    response.add(responseMap);

    HttpHeaders httpHeaders = new HttpHeaders();
    httpHeaders.add("Accept", "application/json");
    return new ResponseEntity<List<Map<String, String>>>(response,
            httpHeaders, HttpStatus.OK);

}

User.java就像这样 -

@XmlRootElement(name = "User")


public class User implements Serializable { 
    private static final long serialVersionUID = 1L;

    private int userId;
    private String name;
    private String email;

    private String company;
    private String gender;

    //getter setter of the data members
}

根据我的理解，使用@RequestPart注释我希望根据其Content-Type评估XML多部分部分，最后将其编组到我的User类中（我使用的是Jaxb2，marshaller / unmarhaller是正确的在应用程序上下文中配置，当我将XML数据作为正文传递并使用@RequestBody注释时，该过程适用于所有其他控制器方法。

但实际发生的情况是，虽然文件被正确找到并解析为MultipartFile，但“用户”部分从未见过，请求总是失败，与控制器方法签名不匹配。

我用几种客户端类型重现了这个问题，我相信多部分请求的格式是可以的。

请帮我解决这个问题，也许会有一些解决方法来接收混合/多部分请求。

谢谢和问候，

Raghvendra

Answer 1

不确定您是否修复了问题，但我也遇到了类似的问题，即在将@RequestPart和MultipartFile混合在一起时，我的控制器无法获取我的JSON对象。

您的通话方法签名看起来是正确的：

public ResponseEntity<List<Map<String, String>>> createUser(
        @RequestPart("file") MultipartFile file, @RequestPart(required=false) User user) {

// ... CODE ... 
}

但请确保您的请求看起来像这样：

POST /createUser
Content-Type: multipart/mixed; boundary=B0EC8D07-EBF1-4EA7-966C-E492A9F2C36E

--B0EC8D07-EBF1-4EA7-966C-E492A9F2C36E
Content-Disposition: form-data; name="user";
Content-Type: application/xml; charset=UTF-8

<user><!-- your user xml --></user>
--B0EC8D07-EBF1-4EA7-966C-E492A9F2C36E
Content-Disposition: form-data; name="file"; filename="A551A700-46D4-470A-86E7-52AD2B445847.dat"
Content-Type: application/octet-stream

/// FILE DATA
--B0EC8D07-EBF1-4EA7-966C-E492A9F2C36E--

Answer 2

我设法解决了问题

端点示例：

@PostMapping("/")
public Document create(@RequestPart Document document,
                       @RequestPart(required = false) MultipartFile file) {
    log.debug("#create: document({}), file({})", delegation, file);
    //custom logic
    return document;
}

例外：

"error_message": "Content type 'application/octet-stream' not supported"

从下一个方法引发异常：

org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodArgumentResolver.readWithMessageConverters(HttpInputMessage,MethodParameter,Type)

解决方案：

我们必须创建自定义转换器@Component，该转换器实现 HttpMessageConverter 或 HttpMessageConverter ，并且了解 MediaType.APPLICATION_OCTET_STREAM 。对于简单的解决方法，只需扩展 AbstractJackson2HttpMessageConverter

@Component
public class MultipartJackson2HttpMessageConverter extends AbstractJackson2HttpMessageConverter {

/**
 * Converter for support http request with header Content-Type: multipart/form-data
 */
public MultipartJackson2HttpMessageConverter(ObjectMapper objectMapper) {
    super(objectMapper, MediaType.APPLICATION_OCTET_STREAM);
}

@Override
public boolean canWrite(Class<?> clazz, MediaType mediaType) {
    return false;
}

@Override
public boolean canWrite(Type type, Class<?> clazz, MediaType mediaType) {
    return false;
}

@Override
protected boolean canWrite(MediaType mediaType) {
    return false;
}
}

Answer 3

您可以从以下位置使用@RequestPart org.springframework.web.bind.annotation.RequestPart; 用作结合@RequestBody和文件上传。

像这样使用@RequestParam @RequestParam（“ file”）MultipartFile文件您只能上传文件和多个单个数据（键值）喜欢

    @RequestMapping(value = "/uploadFile", method = RequestMethod.POST,  consumes = { MediaType.MULTIPART_FORM_DATA_VALUE }, produces = { MediaType.APPLICATION_JSON_VALUE })
    public void saveFile(
                         @RequestParam("userid") String userid,
                         @RequestParam("file") MultipartFile file) {

    }

您可以使用@RequestPart之类的方式发布JSON对象数据和和文件

    @RequestMapping(value = "/patientp", method = RequestMethod.POST,  consumes = { MediaType.MULTIPART_FORM_DATA_VALUE }, produces = { MediaType.APPLICATION_JSON_VALUE })
public ResponseEntity<?> insertPatientInfo(
                                            @RequestPart PatientInfoDTO patientInfoDTO,
                                            @RequestPart("file") MultipartFile file) {
}

您不仅限于直接将分段文件上传用作控制器方法参数。您的表单对象可以包含Part或MultipartFile字段，并且Spring自动知道它必须从文件部分获取值并适当地转换值。

上述方法可以响应先前演示的包含单个文件的多部分请求。之所以可行，是因为Spring具有一个内置的HTTP消息转换器，可以识别文件部分。除了javax.servlet.http.Part类型之外，您还可以将文件上传转换为org.springframework.web.multipart.MultipartFile。如第二个multipart请求所示，如果file字段允许上传多个文件，则只需使用数组或Parts集合或MultipartFiles。

        @RequestMapping(value = "/patientp", method = RequestMethod.POST,  consumes = { MediaType.MULTIPART_FORM_DATA_VALUE }, produces = { MediaType.APPLICATION_JSON_VALUE })
    public ResponseEntity<?> insertPatientInfo(
                                                @RequestPart PatientInfoDTO patientInfoDTO,
                                                @RequestPart("files") List<MultipartFile> files) {
    }

乐于助人...

Answer 4

我设法解决了问题：

    @SuppressWarnings("rawtypes")
@RequestMapping(value = "/DataTransfer", method = RequestMethod.POST, produces = {
        MediaType.APPLICATION_JSON_UTF8_VALUE }, consumes = {  MediaType.MULTIPART_FORM_DATA_VALUE, MediaType.APPLICATION_JSON_UTF8_VALUE} )
@ApiOperation(value = "Sbm Data Transfer Service", response = Iterable.class)
@ApiResponses(value = { @ApiResponse(code = 200, message = "Successfully find."),
        @ApiResponse(code = 400, message = "There has been an error."),
        @ApiResponse(code = 401, message = "You are not authorized to save the resource"),
        @ApiResponse(code = 403, message = "Accessing the resource you were trying to reach is forbidden"),
        @ApiResponse(code = 404, message = "The resource you were trying to reach is not found") })
ResponseEntity processDataTransfer(@RequestPart(name="file") MultipartFile  file, @RequestPart(name="param") DataTransferInputDto param);

Answer 5

你试过吗

ResponseEntity<List<Map<String, String>>> createUser(
        @RequestPart("file") MultipartFile file, @RequestBody(required=false) User user) {

或

ResponseEntity<List<Map<String, String>>> createUser(
        @RequestPart("file") MultipartFile file, @RequestParam(required=false) User user) {

如果这不起作用，您可以向我们展示mapping.xml

带有混合多部分请求的@RequestPart，Spring MVC 3.2

5 个答案: