element ui+spring boot上传图片

element UI代码如下，其中on-success为上传成功之后的回调,:headers为请求头设置，可以设置request的请求头,

          <el-upload class="avatar-uploader" action="/api/shop/file/upload" :show-file-list="false"
            :on-success="uploadSuccess" :before-upload="beforeUpload" :headers="getToken()" :onError="uploadError">
            <img v-if="imageUrl" :src="imageUrl" class="avatar">
            <i v-else class="el-icon-plus avatar-uploader-icon"></i>
          </el-upload>

beforeUpload(file) {
        //let fd = new Formdata()
        //fd.append('key', file.raw, 'fileName')
        // todo
      },
      // 上传成功后的回调
      uploadSuccess(response, file, fileList) {
        if (response.status == 200) {
          this.imageUrl = 'http://localhost:9762/api/shop/file/image/' + response.data
        } else {
          this.$error('上传失败')
        }
      },
      // 上传错误
      uploadError(response, file, fileList) {
        console.log('上传失败，请重试！')
      },
      getToken() {
        var data = { 'token': token().token }
        return data
      },

Java代码如下

@RestController
@Api(value = "uploadController")
@RequestMapping("/api/shop/file")
public class uploadController {
    public static final String ROOT = "upload-dir";

    private final ResourceLoader resourceLoader;

    @Autowired
    public uploadController(ResourceLoader resourceLoader) {
        this.resourceLoader = resourceLoader;
    }

    //显示图片
    @RequestMapping(method = RequestMethod.GET, value = "/image/{filename:.+}")
    @ResponseBody
    public ResponseEntity<?> getFile(@PathVariable String filename) {

        try {
            return ResponseEntity.ok(resourceLoader.getResource("file:" + Paths.get(ROOT, filename).toString()));
        } catch (Exception e) {
            return ResponseEntity.notFound().build();
        }
    }

    //上传图片
    @RequestMapping(value = "upload",method = RequestMethod.POST)
    public Msg upload(MultipartFile file) throws IOException {

        String name=file.getOriginalFilename();
        name=name.substring(name.lastIndexOf("."));
        name=UUID.randomUUID().toString().replace("-","")+name;

        File dir = new File(ROOT);
        if(!dir.exists()){
            dir.mkdirs();
        }
        file.transferTo(Paths.get(ROOT, name));
        return Msg.success().addData(name);
    }
}

<style>
  .avatar-uploader .el-upload {
    border: 1px dashed #d9d9d9;
    border-radius: 6px;
    cursor: pointer;
    position: relative;
    overflow: hidden;
  }

  .avatar-uploader .el-upload:hover {
    border-color: #409EFF;
  }

  .avatar-uploader-icon {
    font-size: 28px;
    color: #8c939d;
    width: 178px;
    height: 178px;
    line-height: 178px;
    text-align: center;
  }

  .avatar {
    width: 178px;
    height: 178px;
    display: block;
  }
</style>