php 微信授权登录

<?php
/**
 *微信授权实例
 */
class ClassName extends AnotherClass
{
    /**
    * wechat oauth 之后的回调页面
    */
    public function callback()
    {
        $this->_globals();
        if (!isset($_GET['code']) || !$_GET['code']) {
             echo "无效的地址";
             exit;
        }
        if ($_SERVER['HTTP_HOST'] == _WECHAT_OAUTH_DOMAIN) {
            //redirect to customer domain
            $customDomain = $_GET['state'];
            $url = "http://" . $customDomain . $_SERVER["REQUEST_URI"];
            header("Location: {$url}");
            exit;
        }
        $wechat = new Wechat($this->client['appid'], $this->client['appsecret']);
        $accessToken = $wechat->getAccessToken($_GET['code']);  //获取accessToken
        $userInfo = $wechat->getUserInfo($accessToken['access_token'], $accessToken['openid']); //获取用户信息

        $thirdUserMdl = model('CoreUserOpenids');
        $filter = array("client_id='{$this->client['id']}'", "utype='wechat'", "openid='{$userInfo['openid']}'");
        $res = $thirdUserMdl->getRow($filter);
       
        $userMdl = model('CoreUsers');
        $user = $userMdl->getRow(array("id='{$res['uid']}'"));

        $_SESSION['login_user'] = $user;
        $_SESSION['wechat_user'] = $res;

        $targetUrl = empty($_SESSION['target_url']) ? '/' : $_SESSION['target_url'];
        header('location:' . $targetUrl);
        exit;
    }


    public function getAuthorizeUrl($redirectUri, $scope = 'snsapi_userinfo', $state = '') {
        $baseurl = 'https://open.weixin.qq.com/connect/oauth2/authorize';
        $params = [
           'appid' => $this->appid,
           'redirect_uri' => $redirectUri,
           'response_type' => 'code',
           'scope' => $scope,
           'state' => $state,
        ];
        $url = $baseurl . '?' . http_build_query($params);
        return $url;
    }


    /**
     * Notes:code 换access_token
     * Created by xxg@seabig.cn
     * Date: 2020/5/8
     * Time: 0:38
     */
   public function getAccessToken($code) {
       $baseurl = 'https://api.weixin.qq.com/sns/oauth2/access_token';
       $params = [
           'appid' => $this->appid,
           'secret' => $this->appsecret,
           'code' => $code,
           'grant_type' => 'authorization_code',
       ];
       $url = $baseurl . '?' . http_build_query($params);
       $ch = curl_init();
       curl_setopt($ch, CURLOPT_URL, $url);
       curl_setopt($ch, CURLOPT_HEADER, 0);
       curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
       curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 10);
       curl_setopt($ch, CURLOPT_TIMEOUT, 15);
       $res = curl_exec($ch);
       curl_close($ch);
       $json_obj = json_decode($res, true);
       $access_token = $json_obj['access_token'];
       $openid = $json_obj['openid'];
       $data = array("access_token" =>$access_token , "openid" => $openid);
       return $data;
   }

    /**
     * Notes:获取用户信息
     * Created by xxg@seabig.cn
     * Date: 2020/5/8
     * Time: 0:39
     */
    public function getUserInfo($access_token,$openid) {
       $baseurl = 'https://api.weixin.qq.com/sns/userinfo';
       $params = [
           'access_token' => $access_token,
           'openid' => $openid,
           'lang' => 'zh_CN',
       ];
       $url = $baseurl . '?' . http_build_query($params);
       $ch = curl_init();
       curl_setopt($ch, CURLOPT_URL, $url);
       curl_setopt($ch, CURLOPT_HEADER, 0);
       curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
       curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 10);
       curl_setopt($ch, CURLOPT_TIMEOUT, 15);
       $res = curl_exec($ch);
       curl_close($ch);
       //解析json
       $userinfo = json_decode($res, true);
       return $userinfo;
    }
}