问题描述：
@RequestMapping(value = "upload", method = RequestMethod.POST,consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
public void upload(@RequestPart MultipartFile upfile) throws Exception {
return fileStorageService.upload(upfile);
}
上面的代码是上传一个文件到upload方法中，然后在该方法中调用fileStorageService（FeignClient）去上传
fileStorageService.upload方法如下：
@FeignClient(name = "STORAGE")
@RequestMapping("/file")
public interface FileStorageService {
@PostMapping(value = "/upload",consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
String upload(@RequestPart MultipartFile file);
}
在实际运行过程中，报错：
org.springframework.web.multipart.support.MissingServletRequestPartException: Required request part 'file' is not present
问题原因
因为upfile的属性是upfile，而不是file，传递到fileStorageService.upload方法中的时候，找不到file标记的文件内容
解决方案
方案一：让两个方法的参数名一致
方案二：处理upfile对象，让它生成一个新的MutipartFile对象
MultipartFile multipartFile = new MultipartFileDto(PlatformStorage.MinioMutipartFileFieldName.FIELD_NAME, bytes);
//自定义一个MultipartFile
public class MultipartFileDto implements MultipartFile {
private final String name;
private String originalFilename;
private String contentType;
private final byte[] content;
/**
* Create a new MultipartFileDto with the given content.
* @param name the name of the file
* @param content the content of the file
*/
public MultipartFileDto(String name, byte[] content) {
this(name, "", null, content);
}
/**
* Create a new MultipartFileDto with the given content.
* @param name the name of the file
* @param contentStream the content of the file as stream
* @throws IOException if reading from the stream failed
*/
public MultipartFileDto(String name, InputStream contentStream) throws IOException {
this(name, "", null, FileCopyUtils.copyToByteArray(contentStream));
}
/**
* Create a new MultipartFileDto with the given content.
* @param name the name of the file
* @param originalFilename the original filename (as on the client's machine)
* @param contentType the content type (if known)
* @param content the content of the file
*/
public MultipartFileDto(String name, String originalFilename, String contentType, byte[] content) {
this.name = name;
this.originalFilename = (originalFilename != null ? originalFilename : "");
this.contentType = contentType;
this.content = (content != null ? content : new byte[0]);
}
/**
* Create a new MultipartFileDto with the given content.
* @param name the name of the file
* @param originalFilename the original filename (as on the client's machine)
* @param contentType the content type (if known)
* @param contentStream the content of the file as stream
* @throws IOException if reading from the stream failed
*/
public MultipartFileDto(String name, String originalFilename, String contentType, InputStream contentStream)
throws IOException {
this(name, originalFilename, contentType, FileCopyUtils.copyToByteArray(contentStream));
}
@Override
public String getName() {
return this.name;
}
@Override
public String getOriginalFilename() {
return this.originalFilename;
}
@Override
public String getContentType() {
return this.contentType;
}
@Override
public boolean isEmpty() {
return (this.content.length == 0);
}
@Override
public long getSize() {
return this.content.length;
}
@Override
public byte[] getBytes() throws IOException {
return this.content;
}
@Override
public InputStream getInputStream() throws IOException {
return new ByteArrayInputStream(this.content);
}
@Override
public void transferTo(File dest) throws IOException, IllegalStateException {
FileCopyUtils.copy(this.content, dest);
}
}
方案三：升级springboot和springcloud
我发现这个问题在2.1.7.RELEASE和Greenwich.SR2下会出现，但是升级到2.4.0和2020.0.4后就不会出现，直接这样使用没问题
