微信服务号授权域名中转方案

微信授权域名现在只允许填写两个
我们可以在其中一个安全域名下，弄一个中转地址

比方说授权域名填写a.abc.com
我们在a.abc.com
弄一个a.abc.com/jump.php

class Jump{
        private $app_id     = 'abc';

        private $app_secret = 'cba';
      
        public function geturl(){
            return $this->get_authorize_url('a.abc.com/givecode.php'); //中转回调地址
        }
      
        public function get_authorize_url($redirect_uri = '', $state = ''){
            $reurl = b.abc.com; //真正想要回调的地址
            $redirect_uri = urlencode($redirect_uri);
            return "https://open.weixin.qq.com/connect/oauth2/authorize?appid={$this->app_id}&redirect_uri={$redirect_uri}&response_type=code&scope=snsapi_base&state={$reurl}#wechat_redirect";

        }
      
    }

    $obj = new Jump();
    $url = $obj->geturl();
    Header("Location: $url");

然后在givecode.php

    $code = $_GET['code'];  $state = urldecode($_GET['state']);
    $token_url = "https://api.weixin.qq.com/sns/oauth2/access_token?appid=&secret=&code={$code}&grant_type=authorization_code";
    $token_data = file_get_contents($token_url);
    $token_data = json_decode($token_data);
    if($token_data->openid){
        $openid = $token_data->openid;

        $url = $state;
        setcookie("openid",$openid,time()+3600,'/','abc.com');
        Header("Location: $url");
    }

最后在b.abc.com拿到openid
用户详细信息也大致同一个思路