Regarding the Alipay payment interface, what should my PHP provide to iOS? How to write it?

 $list = array(
            'partner'                 =>$alipay_config['partner'],
            '_input_charset'          =>$alipay_config['input_charset'],
            'notify_url'              =>'http://notify.msp.hk/notify.htm',
            "return_url"              => $alipay_config['return_url'],
            "it_b_pay"                => "30m",
            'service'                 =>$alipay_config['service'],
            'seller_id'               =>$alipay_config['partner'],
            "anti_phishing_key"       =>$alipay_config['anti_phishing_key'],
            "exter_invoke_ip"         =>$alipay_config['exter_invoke_ip'],
        //订单号
            'out_trade_no'            =>$order_id,
        //商品名称
            'subject'                 =>$skills,
        //支付类型
            'payment_type'            =>'1',
        //金额
            'total_fee'               =>$recharge_moeny,
        //描述
            'body'                    =>$order_id,
    );
    //建立请求
    $alipaySubmit = new \AlipaySubmit($alipay_config);
    $html_text = $alipaySubmit->buildRequestParaToString($list);
    // 返回签名的数据
    return $html_text;
}

}