php版微信实现登录授权的实例

用户授权也是高级接口那部分内容，只是把它独立出来，这样让整个微信框架条理清晰些，但我们用它首先要在微信后台设置OA2的URL，这里的URL和教程一的有所不同。它是不带http://开头的域名。
首先登陆你的微信后台找到《开发者中心》：

点击修改填入我们的域名如下格式：

好了，最基本要点的OA2要求搞好，下面我们用个WechatAuth类生成一个OA2的URL格式，然后再从服务号里，以链接或者菜单又或者图文，跳到微信内置的WEB里就实现了我们取openid或者授权取用户消息！

例子代码生成snsapi_base或者snsapi_userinfo：
$auth = new WechatAuth(array(
        WechatAuth::APP_ID => 'wx32259fc5sd5aac12B',
        WechatAuth::APP_SECRET => '7ef73d3c56fcd0d984862ff217d2c648',
    ));
    $url = $auth->getLoginUrl(array(
        'redirect_uri' => 'http://www.demo.com/wp/ken',
        'scope' => 'snsapi_userinfo' //snsapi_base
    ));
    echo $url;

执行后，我们会得到如下OA2的URL：

https://open.weixin.qq.com/connect/oauth2/authorize?appid=wx32259fc5d5aac13d&redirect_uri=http%3A%2F%2Fwww.demo.com%2Fwp%2Fken&response_type=code&scope=snsapi_userinfo&state=STATE#wechat_redirects

然后我们在服务号里以刚才说到的菜单好，链接好 点击转到微信内置的浏览器里，如果你的scope方式为snsapi_userinfo时会弹出授权界面，base时不会弹默认执行后会返回openid：

好了，OA2无非就是让我们生成特定格式的URL，让我们点过去取openid或者用户信息（无论是否关注了你的服务号，只要确认授权）,可以运用本站微信的实例有相关OA2的运用或者留言给我！
WechatAuth类：

/**
 * 微信 OAuth2.0授权接口
 * Class WechatAuth
 */
class WechatAuth {
 
    const
        JSON = 'json',
        POST = 'post',
        GET = 'get',
        APP_ID = 'appid',
        APP_SECRET = 'secret',
        API_URL_PREFIX = 'https://api.weixin.qq.com/sns';
 
    public
        $_error_number = 0,
        $_error,
        $_APPID,
        $_APPSECRET;
 
    protected
        $_cache = array(),
        $_options,
        $_openid,
        $_access_token,
        $_refresh_token,
        $_timeout = 30;
 
    static protected
        $_instance;
 
    /**
     * 单例模式
     * @param array $options
     * @return WechatAuth
     */
    static public function getInstance(array $options = array()) {
        if (empty(self::$_instance)) {
            self::$_instance = new WechatAuth($options);
        }
 
        return self::$_instance;
    }
 
    /**
     * @param array $options {WechatAuth::APP_ID:"", WechatAuth::APP_SECRET:""}
     */
    public function __construct(array $options = array()) {
        $this->_options = array(
            'timeout' => $this->_timeout,
        );
        $_options = array_merge($this->_options, $options);
        $this->_APPID = $_options['appid'];
        $this->_APPSECRET = $_options['secret'];
        $this->_timeout = $_options['timeout'];
    }
 
    /**
     * 提交请求
     * @param $url
     * @param array $params
     * @param string $type Webchat_API::POST|Webchat_API::GET
     * @return bool|mixed
     */
    public function request($url, $params = array(), $type = self::POST) {
        $ch = curl_init();
        if ($type == self::GET) {
            $url = $url.'?'.http_build_query($params);
        }
        curl_setopt_array($ch, array(
            CURLOPT_URL => $url,
            CURLOPT_TIMEOUT => $this->_timeout,
            CURLOPT_USERAGENT => 'wordpress_wechat_client/0.1.'.rand(1,6),
            CURLOPT_HEADER => 0,
            CURLOPT_FOLLOWLOCATION => 1,
            CURLOPT_RETURNTRANSFER => 1,
            CURLOPT_SSL_VERIFYPEER => 0,
            CURLOPT_SSLVERSION => 3,
//            CURLOPT_VERBOSE => 1,
        ));
        if ($type == self::POST) {
            curl_setopt($ch, CURLOPT_PORT, 1);
            curl_setopt($ch, CURLOPT_POSTFIELDS, $params);
        }
        if ($type == self::JSON) {
            //微信的破接口竟然不支持unicode转义符，违反JSON协定，只能把JSON字符中的unicode转回来
            $data = preg_replace('/\\\\u([a-f0-9]{4})/e', "json_decode('\"$0\"', 1)", json_encode($params));
            curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
            curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type:application/json'));
        }
        $res = curl_exec($ch);
        $this->_error_number = curl_errno($ch);
        $this->_error = curl_error($ch);
        curl_close($ch);
 
        if ($this->_error_number) {
            return false;
        }
        return $this->parseResult($res);
    }
 
    /**
     * 处理返回结果
     * @param $res
     * @return bool|mixed
     */
    protected function parseResult($res) {
        $res = json_decode($res, true);
        if (!empty($res)) {
            if (isset($res['errcode']) && $res['errcode']) {
                $this->_error_number = $res['errcode'];
                $this->_error = $res['errmsg'];
                return false;
            }
 
            return $res;
        }
 
        return false;
    }
 
    /**
     * 获取当前URL
     * @return string
     */
    static public function getCurrentUrl() {
        $pageURL = 'http';
        if (isset($_SERVER["HTTPS"]) && $_SERVER["HTTPS"] == "on") {
            $pageURL .= "s";
        }
        $pageURL .= "://";
        if (isset($_SERVER['SERVER_PORT']) && $_SERVER["SERVER_PORT"] != "80") {
            $pageURL .= $_SERVER["SERVER_NAME"] . ":" . $_SERVER["SERVER_PORT"] . $_SERVER["REQUEST_URI"];
        } else {
            if(isset($_SERVER["SERVER_NAME"]) && isset($_SERVER["REQUEST_URI"]))
                $pageURL .= $_SERVER["SERVER_NAME"] . $_SERVER["REQUEST_URI"];
        }
        return $pageURL;
    }
 
    /**
     * 获取访问token
     * @param bool $refresh 是否强制刷新
     * @return bool|mixed
     */
    public function getAuthAccessToken($refresh = false) {
        $code = isset($_GET['code']) ? $_GET['code'] : '';
        $state = isset($_GET['state']) ? $_GET['state'] : '';
        $cache = $this->cache('auth_access_token');
        if ($cache && ! $refresh) {
            return array('access_token' => $cache, 'code' => $code, 'state' => $state);
        }
        $res = $this->request(self::API_URL_PREFIX.'/oauth2/access_token', array(
            self::APP_ID => $this->_APPID,
            self::APP_SECRET => $this->_APPSECRET,
            'code' => $code,
            'grant_type' => 'authorization_code',
        ), self::GET);
        if ($res) {
            $this->cache('auth_access_token', $res['access_token']);
            $this->cache('auth_refresh_token', $res['refresh_token']);
            $this->cache('auth_openid', $res['openid']);
        } else {
            if ($this->_error_number == 42001) {
                return $this->refreshAccessToken();
            }
        }
       return array('access_token' => $res['access_token'], 'code' => $code, 'state' => $state);
    }
 
    /**
     * 刷新访问token
     * @return mixed
     */
    public function refreshAccessToken() {
        $code = isset($_GET['code']) ? $_GET['code'] : '';
        $state = isset($_GET['state']) ? $_GET['state'] : '';
        $cache = $this->cache('auth_refresh_token');
        if ($cache) {
            $this->_refresh_token = $cache;
        }
 
        $res = $this->request(self::API_URL_PREFIX.'/oauth2/refresh_token', array(
            self::APP_ID => $this->_APPID,
            'refresh_token' => $this->_refresh_token,
            'grant_type' => 'refresh_token',
        ), self::GET);
 
        if ($res) {
            $this->cache('auth_access_token', $res['access_token']);
            $this->cache('auth_refresh_token', $res['refresh_token']);
            $this->cache('auth_openid', $res['openid']);
        }
        return array('access_token' => $res['access_token'], 'code' => $code, 'state' => $state);
    }
 
    /**
     * 获取用户信息
     * @param bool $refresh 是否强制刷新
     * @return bool|mixed
     */
    public function getUserInfo($refresh = false) {
        $this->_access_token = $this->getAuthAccessToken($refresh);
        $cache =  $this->cache('auth_openid');
        if ($cache) {
            $this->_openid = $cache;
        }
 
        $res = $this->request(self::API_URL_PREFIX.'/userinfo', array(
            'access_token' => $this->_access_token,
            'openid' => $this->_openid,
        ), self::GET);
 
 
        if ($res) {
            return $res;
        }
 
        return false;
    }
 
    /**
     * 获取用户授权地址
     * @param array $options
     * @return string
     */
    public function getLoginUrl($options = array()) {
        $_options = array(
            self::APP_ID => $this->_APPID,
            'redirect_uri' => self::getCurrentUrl(),
            'response_type' => 'code',
            'scope' => 'snsapi_base', //snsapi_base | snsapi_userinfo
            'state' => 'STATE',
        );
        $params = array_merge($_options, $options);
 
        return 'https://open.weixin.qq.com/connect/oauth2/authorize?'.http_build_query($params).'#wechat_redirects';
    }
 
    /**
     * 缓存接口Session实现
     * @param $key 缓存索引key
     * @param null $value 缓存值
     * @return bool|mixed
     */
    public function cache($key, $value = null) {
        if (!session_id()) {
            session_start();
        }
        if (empty($value)) {
            if (isset($_SESSION[$key])) {
                return $_SESSION[$key];
            }
            return false;
        }
        $_SESSION[$key] = $value;
        return false;
    }
}