Facebook API:使用JavaScript SDK登录,然后使用PHP检查登录状态

Question

当用户单击"登录"按钮时,我正在使用Facebook的JavaScript SDK来显示"登录弹出窗口".

代码是,正如Facebook在doucmentation中提供的:

$(".loginButton").click(function(){
 FB.login(function(response) {
    FB.api('/me', function(response) {
       console.log(response.id);
       //User ID shows up so I can see that the user has accepted the app.
     });
 });

我还可以FB.getLoginStatus()用来检查用户是否确实已登录并接受了该应用程序.

但是,现在我想用PHP执行一个函数.据我所知,PHP已$user成功登录后分配了UserID.

问题是JS登录后$user仍然存在0.我卡住了,我无法弄清楚为什么它不会分配正确的用户ID$user

这是我的JS:

    <script type="text/javascript">  

        window.fbAsyncInit = function() {
            FB.init({
                appId  : '<?php echo $AppId; ?>',
                status : true, // check login status
                cookie : true, // enable cookies to allow the server to access the session
                xfbml  : true,
                channelUrl  : '<?php echo $ServerPath; ?>channel.php' // custom channel
            });

    }; 


    //Get Login Status
    function amILoggedIn(){
        var toreturn = "";
        FB.getLoginStatus(function(response) {
            if (response.status === 'connected') {
                window.userId =  response.authResponse.userID;
            toreturn = "GetLoginStatus: logged in" + " " + "<?php echo $user; ?>";
            } else {
            toreturn = "GetLoginStatus: Logged Out";
            }
            console.log(toreturn);
        }); 


    };


    // Load the SDK asynchronously
    (function(d, s, id){
         var js, fjs = d.getElementsByTagName(s)[0];
         if (d.getElementById(id)) {return;}
         js = d.createElement(s); js.id = id;
         js.src = "//connect.facebook.net/en_US/all.js";
         fjs.parentNode.insertBefore(js, fjs);
       }(document, 'script', 'facebook-jssdk'));

            var obj = {
                    method: 'feed',
                    link: 'http://www.google.com'
                };


    $(".loginPopupButton").click(function(){
         FB.login(function(response) {
            FB.api('/me', function(response) { //user-specific stuff
               console.log(response.id);
             });
         });

    });

    </script>

这是PHP:

    <?php
    include_once('fbapi/facebook.php');
    include_once('fbapi/Authenticated_User.php');
    include_once('config.php');


    // Create our Application instance.
    $facebook = new Facebook(array(
                    'appId'  => $AppId,
                    'secret' => $AppSecret
                ));
    //Facebook Authentication part
    $user = $facebook->getUser();


    $perms = "manage_pages";
    if(isset($_GET['backlink']))
        $redirectUrl   = urldecode($_GET['backlink']);
    else
        $redirectUrl   = $fullserverpath;

    $cancelUrl   = $ServerPath."index.php?page=loginWFb";

    //AA - where to go to get FB popup.    
    $loginUrl = $facebook->getLoginUrl(
            array(
                'scope' => $perms,
                'redirect_uri' => $redirectUrl,
                'cancel_uri' => $cancelUrl
            )
    );



    //AA- Defining that a powerUSER is someone who's logged in
    if(isset($user)){
        $_SESSION['loggedIn'] = $user;

    }

    ?>

Answer 1

使用 JS SDK 登录将登录数据存储在 Facebook cookie 中，而使用 PHP SDK 登录将数据存储在 PHP 会话中。因此，如果您使用 JS SDK 登录，PHP SDK 将不会意识到这一点。

要使用 JS SDK 数据登录 PHP SDK，您需要在查询参数中使用签名请求来调用 PHP 页面：

FB.getLoginStatus(function(response) {
    if (response.status === 'connected') {
        // Full redirect or ajax request according to your needs
        window.location.href = 'login.php?signed_request='+response.authResponse.signedRequest;
    }
});

然后$facebook->getUser()将在 PHP 代码中为您提供用户 ID。