多站点微信公众号网页授权处理

        我们经常需要多个站点微信网页授权登录，以前公众号只能设置一个授权域名，现在也只能设置两个，如果是三个、四个改怎么办呢？下面详细介绍解决办法

一、新建站点

        需要新建一个站点，专门放授权中间件，其余的站点只需要访问这个站点，就可以获取到微信授权信息，然后在公众号后台—》公众号设置—》功能设置—》网页授权域名，设置中间件的域名。

        中间件代码如下：

<?php

if(is_HTTPS()){
    $protocol = 'https';
} else {
    $protocol = 'http';
}
if(isset($_GET['device'])){
    $device = $_GET['device'];
}
if(isset($_GET['appid'])){
    $appid = $_GET['appid'];
}
if(isset($_GET['state'])){
    $state = $_GET['state'];
}
if(isset($_GET['redirect_uri'])){
    $redirect_uri = $_GET['redirect_uri'];
}
if(isset($_GET['code'])){
    $code = $_GET['code'];
}
if(isset($_GET['scope'])){
    $scope = $_GET['scope'];
}

if($code == 'test'){
    exit;
}
if(empty($code)){
    $authUrl = '';
    if($device == 'pc'){
        $authUrl = 'https://open.weixin.qq.com/connect/qrconnect';
    } else {
        $authUrl = 'https://open.weixin.qq.com/connect/oauth2/authorize';
    }
    $options = [
        $authUrl,
        '?appid=' . $appid,
        '&redirect_uri=' . urlencode($protocol . '://' . $_SERVER['HTTP_HOST'] . '/index.php?redirect_uri='.$redirect_uri),
//                '&redirect_uri=' . urlencode($redirect_uri),
        '&response_type=code',
        '&scope=' . $scope,
        '&state=' . $state,
        '#wechat_redirect'
    ];

    $domain = getDomain();
    //把redirect_uri先写到cookie
    header(implode('', [
        "Set-Cookie: redirect_uri=",
        urlencode($redirect_uri),
        "; path=/; domain=",
        $domain,
        "; expires=" . gmstrftime("%A, %d-%b-%Y %H:%M:%S GMT", time() + 60),
        "; Max-Age=" + 60,
        "; httponly"
    ]));
    header('Location: ' . implode('', $options));
}else{
    if(isset($redirect_uri)){
        $back_url = urldecode($redirect_uri);
        header('Location: ' . implode('', [
                $back_url,
                strpos($back_url, '?') ? '&' : '?',
                'code=' . $code,
                '&state=' . $state
            ]));
    }
}
function is_HTTPS(){
    if(!isset($_SERVER['HTTPS'])) return FALSE;
    if($_SERVER['HTTPS'] === 1){  //Apache
        return TRUE;
    } elseif($_SERVER['HTTPS'] === 'on'){ //IIS
        return TRUE;
    } elseif($_SERVER['SERVER_PORT'] == 443){ //其他
        return TRUE;
    }
    return FALSE;
}
function getDomain(){
    $server_name = $_SERVER['SERVER_NAME'];
    if(strpos($server_name, 'www.') !== false){
        return substr($server_name, 4);
    }
    return $server_name;
}

二、站点调用中间件（以ThinkPHP5为例）

        代码如下：

if(empty(input('code'))){
    // 获取传递的参数
    $get_var_param = http_build_query(input('get.'));
    // 授权成功后跳转的地址
    $redirecturl = urldecode('http://'.$_SERVER['HTTP_HOST'].'/common/index?'.$get_var_param);
    // 准备scope为snsapi_userInfo网页授权页面
    $snsapi_userInfo_url = 'http://wx.api.laozijk.com?appid='.$_appid.'&redirect_uri='.$redirecturl.'&scope=snsapi_userinfo';
    redirect($snsapi_userInfo_url);
}else{
    // 下面两个方法将在下一篇微信接口扩展中讲到
    $weixin = controller('weixin');
    // 获取access_token
	$jsonStr = $weixin->getOauthAccessToken();
    // 获取用户信息
	$user_info = $weixin->getOauthUserInfo($jsonStr['access_token'],$jsonStr["openid"]);
}