oop中 限制文件类型和大小

<?php
/**
 * Created by IntelliJ IDEA.
 * User: jiabinwang
 * Date: 7/5/18
 * Time: 8:46 PM
 */

namespace ElemeOpenApiEfs;

use ElemeOpenApiApiContentService;
use ElemeOpenApiConfigConfig;
use ElemeOpenApiExceptionBusinessException;

class UploadVideoClient
{
    private $config;
    private $token;

    private $file_ext_list = array("MP4", "MOV");
    private $file_max_size = 200;

    public function __construct($token, Config $config)
    {
        $this -> config = $config;
        $this -> token = $token;
    }

    /**
     * 上传视频（封装ContentService中上传视频和获取efs配置接口）
     *
     * @param $file_path 视频文件本地地址
     * @param $title 视频标题
     * @param $desc 视频描述
     * @param $video_type 视频类型
     * @param $shop_id 店铺Id
     * @return mixed
     * @throws BusinessException 业务异常
     */
    public function upload_video_client($file_path, $title, $desc, $video_type, $shop_id) {
        $file_extension = strtoupper(pathinfo(basename($file_path), PATHINFO_EXTENSION));

        if (!in_array($file_extension, $this -> file_ext_list)) {
            throw new BusinessException("只支持mp4和mov格式的视频");
        }

        if (filesize($file_path) > $this -> file_max_size * 1024 * 1024) {
            throw new BusinessException("视频大小不能超过200M");
        }
}