如何在ElementUI的上传组件el-upload中设置header

axios.interceptors.request.use(config=>{
  NProgress.start();
  // 发送请求需带上token
  config.headers.Authorization=window.sessionStorage.getItem("token")
  return config;
})

 <el-upload
              action="http://127.0.0.1:8888/api/private/v1/upload"
              :headers="headerObj"
              :on-preview="handlePreview"
              :on-remove="handleRemove"
              :on-success="handleSuccess"
              list-type="picture"
            >
              <el-button size="small" type="primary">点击上传</el-button>
              <div slot="tip" class="el-upload__tip">
                只能上传jpg/png文件，且不超过500kb
              </div>
            </el-upload>

headerObj: {
        Authorization: window.sessionStorage.getItem("token"),
      },

<el-upload
   class="upload-demo"
   ref="uploadFile"
   :on-change="beforeUpload"
   :action="uploadUrl"
   :headers="myHeader"
   :on-remove="handleRemove"
   :before-remove="beforeRemove"
   :limit="1"
   :auto-upload="false"
   :on-exceed="handleExceed"
>
<el-button size="small" type="primary">选择文件</el-button>

addDialogClose(){
  this.$refs.ruleForm.resetFields();
  this.addClassroomShow = false
  this.$refs.upload.clearFiles();
}

beforeUpload(file) {
  if(/\.(mp4|m3u8|rmvb|avi|swf|3gp)$/.test(file.name)) {
     this.ruleForm.uploadUrl = this.vidoeUploadUrl
  }else{
     this.ruleForm.uploadUrl = this.fileUploadUrl
  }
  this.$nextTick(()=>{
     this.$refs.uploadFile.submit()
  })
},