element <el-upload>组件传参

后端不从文件流里获取文件名，想让前端传。

   <el-upload
      accept="video/mp4"
      :action="action"
      :headers="uploadHeader"
      :data="uploadData"
      :before-upload="beforeUpload"
      ref="uploader"
    >
      <i class="el-icon-upload"></i>
      <div class="el-upload__text">
        将视频拖到此处，或
        <em>点击上传</em>
      </div>
    </el-upload>
    
    
    //不请求接口
        beforeUpload(file) {
          this.uploadData = { fileName:file.name }
          return new Promise((resolve) => {
            this.$nextTick(function () {
              resolve(true)
            })
          })
        }
    
    //请求接口（七牛）
     beforeUpload(file) {
       return this.$axios
        .get('/v1.1/Qiniu/GetUploadToken')
        .then(res => {
          this.uploadData = {
            key,
            token: res.data.Token
          }
        })
        .catch(err => {
          this.$message({
            type: 'error',
            message: this.$getErrMsg(err)
          })
        })
    }