php 微信授权登录 40029错误

php 微信授权登录 40029错误

public function getUserDetail(){
$appid = "xxxxxxxxxxxx";
$redirect_uri = urlencode("www.xxx你的后台入口xx.com/getUserInfo");

$url = 'https://open.weixin.qq.com/connect/oauth2/authorize?appid='.$appid.'&redirect_uri='.$redirect_uri.'&response_type=code&scope=snsapi_userinfo&state=123#wechat_redirect';
header('location:'.$url);
}

public function getUserInfo(){
$appid = "xxxxxxx";
$appsecret = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxx";

$code   = $_GET['code'];

if ($_SESSION[$code]) {//判断是否已经存在，如存在直接使用code
//先获取token
$url = 'https://api.weixin.qq.com/sns/oauth2/access_token?appid='.$appid.'&secret='.$appsecret.'&code='.$code.'&grant_type=authorization_code';
$res = $this->http_curl($url,'get');
$access_token = $res['access_token'];
$openid = $res['openid'];
var_dump($access_token);
//获取信息
$url = 'https://api.weixin.qq.com/sns/userinfo?access_token='.$access_token.'&openid='.$openid.'&lang=zh_CN';
$res = $this->http_curl($url);
var_dump($res);
} else {
$_SESSION[$code] = $code;
}
}