xyzshop/helper/refill/api/xyz/jianjiao/config.php

<?php
namespace refill\jianjiao;

class config
{
    const ORDER_URL = 'https://jj.dmjvip.com/index.php/third/mobile/createOrder';
    const QUERY_URL = 'https://jj.dmjvip.com/index.php/third/mobile/queryOrder';
    const BALANCE_URL = 'https://jj.dmjvip.com/index.php/third/account/queryAmount';

    const APP_KEY = '3l6kd2yqsvcwftij';
    const APP_SECRET = '3qe7jlk2t5a6gwd01ymxnzuoc48vphbi';
    const NOTIFY_URL = BASE_SITE_URL . "/mobile/callback/refill_jianjiao.php";

    const ExtHeaders = ['Content-Type: application/json;charset=UTF-8'];

    public static function sign($params)
    {
        ksort($params);
        $content = '';
        foreach ($params as $key => $value) {
            if(self::check_empty($value) === false) {
                $content .= "{$key}={$value}&";
            }
        }
        $content .= 'app_secret='.config::APP_SECRET;
        return md5($content);
    }

    public static function check_empty($value)
    {
        if (!isset($value))
            return true;
        if ($value === null)
            return true;
        if (trim($value) === "")
            return true;

        return false;
    }
}