JS上传文件重命文件名

// 选择图片后的处理
    handleSelect(file, fileList) {
      let image = new Image()
      image.src = file.url
      image.onload = () => {
        if (image.width > 900) {
          compressImage(image).then(res=>{
            this.uploadImage(res)
          })
        } else {
          //给图片重新命名，以免同名被覆盖
          const filename = file.uid + this.$cache.local.getJSON('bestUserInfo').userId + file.name
          const renameFile = new File([file.raw], filename, {type: 'image/jpeg', lastModified: Date.now()});
          this.uploadImage(renameFile)
        }
      }
    },