How do I implement a facebook PHP Login as a fallback to single sign on with FBML_问答_开发者

How do I implement a facebook PHP Login as a fallback to single sign on with FBML

开发者 https://www.devze.com 2023-02-11 12:44 出处：网络

I have a working single sign on for facebook that works (most of the time) But for whatever reason I occasionally get an error. I\'m trying to write a fallback method that uses the php sdk login that

I have a working single sign on for facebook that works (most of the time) But for whatever reason I occasionally get an error. I'm trying to write a fallback method that uses the php sdk login that directs to facebook and then forwards back to the url, once facebook redirects back to my page I can see session data in the URL under $_GET['session'] as a json string, I need to figure out how to use that string to make valid API calls.

    <?php 
require_once "facebook_sdk.php";

$facebook = new Facebook(array('appId' => '123','secret' => '456','cookie' => true,));

$session = null;
$_fb_profile = null;

$session = $facebook->getSession();

//get links for login/logout
$loginUrl = $facebook->getLoginUrl();
$logoutUrl = $facebook->getLogoutUrl();

if($session){
    try {

        $facebook_id = $facebook->getUser();
        $_fb_profile = $facebook->api('/me'); //if not null valid session

        $facebook_name = $_fb_profile['name'];
        $facebook_link = $_fb_profile['link'];  
    }
    catch (FacebookApiException $e) {
        echo $e;
    }
}
//there is not a valid session though the single sign on FBML button, try checking php login
if(!$_fb_profile){

    $session = $_GET['session'];//json string from facebook
    $session = json_decode($session);//make into an array

    try {
        $facebook->setSession($session,true);//need to set the session some how with $_GET['session']

        $facebook_id = $facebook->getUser();
        $_fb_profile = $facebook->api('/me');

        $facebook_name = $_fb_profile['name'];
        $facebook_link = $_fb_profile['link'];  
    }
    catch (FacebookApiException $e) {
        die($e); //getting invalid OAuth access token
    }
}

?>
<div id="fb-root"></div>
    <script>
      window.fbAsyncInit = function() {
        FB.init({
          appId   : '<?php echo $facebook->getAppId(); ?>',
          session : <?php echo json_encode($session); ?>, // don't refetch the session when PHP already has it
          status  : true, // check login status
          cookie  : true, // enable cookies to allow the server to access the session
          xfbml   : true // parse XFBML
        });

        // whenever the user logs in, we refresh the page
        FB.Event.subscribe('auth.login', function() {
          window.location.reload();
        });
      };

      (function() {
        var e = document.createElement('script');
        e.src = document.location.protocol + '//conn开发者_开发技巧ect.facebook.net/en_US/all.js';
        e.async = true;
        document.getElementById('fb-root').appendChild(e);
      }());
    </script>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />

</head>
<body>

    <?php if(!$session || !$_fb_profile){   
    //user is not logged in show FBML button and php login link
    echo "<fb:login-button perms='email,user_birthday,user_education_history,read_friendlists,publish_stream'></fb:login-button>
    <p class='small' style='float:right;'>Having trouble? try  <a href='$loginUrl'>logging in here</a></p>";
}
else{
    //user has logged in
    echo "You are logged into facebook as <a href='$facebook_link'>$facebook_name</a>";

}?>

</body>
</html>