php - 验证 facebook canvas 应用程序返回 ?code=

Question

我的 facebook canvas 应用有问题，目前正在开发中 http://localhost:8080

我的 Canvas url 是 http://localhost:8080/fbcanvas/

在 facebook 上，url 设置为 http://apps.facebook.com/app_name/

问题是在用户批准我的应用程序后，我得到一个代码作为 $_GET['code'] 变量。 在 facebook 文档中，它没有说任何有关获取 $_GET['code'] 的信息，它只是说获取 signed_request

这是我在 facebook 示例中使用的代码。

    require_once($_SERVER['DOCUMENT_ROOT'] . '/classes/Page.php');
require($_SERVER['DOCUMENT_ROOT'] . '/core/config.fb.php');

$canvas_page = 'http://apps.facebook.com/khawamusic/';
$auth_url = 'https://www.facebook.com/dialog/oauth?client_id=' . $app_id . '&redirect_uri=' . urlencode($canvas_page);
$signed_request = $_REQUEST['signed_request'];

list($encoded_sig, $payload) = explode('.', $signed_request, 2);

$data = json_decode(base64_decode(strtr($payload, '-_', '+/')), true);

if(empty($data['user_id'])) {
    echo('<script> top.location.href="' . $auth_url .'";</script>');
} else {

    $page = new Page;

    $styles = array('reset.css', 'fbcanvas.css');
    $scripts = array(
        'https://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js', 
        'https://ajax.googleapis.com/ajax/libs/jqueryui/1.8.14/jquery-ui.min.js',
        'http://connect.facebook.net/en_US/all.js#xfbml=1',
        '/sources/js/fbcanvas.js'
    );


    $page->set_title('Khawa');
    $page->set_styles($styles);
    $page->set_scripts($scripts);
    $page->start_page();
    require($_SERVER['DOCUMENT_ROOT'] . '/fbcanvas/fb.tpl');
    $page->end_page();

}

所以发生的事情是用户批准我的应用程序，然后他被重定向到 http://apps.facebook.com/khawamusic/?code=blabla

我很困惑，因为在文档中它没有说我应该得到一个 $_GET['code']

Answer 1

如果用户按下“允许”，则您的应用已获得授权。 OAuth 对话框会将用户的浏览器重定向(通过 HTTP 302)到您在 redirect_uri 参数中使用授权代码传递的 URL:

http://YOUR_URL?code=A_CODE_GENERATED_BY_SERVER

有了这段代码，您可以继续下一步，即应用身份验证，以获得进行 API 调用所需的访问 token 。

引用:https://developers.facebook.com/docs/authentication/

编辑: 这是身份验证的示例，这不会显示 ?code=Blabla.. 首先从这里下载最新的 Facebook PHP SDK:https://github.com/facebook/php-sdk/tree/master/src

确保保存所有 3 个文件，facebook.php、base_facebook.php 和 fb_ca_chain_bundle.crt 现在将文本“YOUR_APP_ID”和“YOUR_APP_API_SECRET”替换为来自 Facebook 的应用程序 ID 和 App Secret，我已经添加了使用图形 API 的样本墙发布，如果你不想，你可以删除它，如果你通过我的代码和评论，你会明白它的作用，你不想做任何事情来获取访问 token ，只需使用 $access_token 变量，它会给你当前用户的 access_token 如果你想要用户的 ID 那么使用 $user 变量，如果你想要用户的基本信息，使用 $userInfo 变量，它会使用 graph api 获取用户的数据并返回数组中的所有信息，你将获得当前用户的信息，如 id、name、first_name、last_name ,link,hometown,location,bio,work,education,gender,timezone.etc.

将 $RedirectUrl 更改为您的着陆页 URL 或 Canvas 页面 url

 <?php
        require 'facebook.php';

        define('FACEBOOK_APP_ID', "YOUR_APP_ID"); // Your App ID
        define('FACEBOOK_SECRET', "YOUR_APP_API_SECRET"); // Your App API Secret

        $RedirectUrl = "http://apps.facebook.com/myapp/"; // Your Landing Page URL, User's will be redirect to this URL after they allow your app.

        function d($d){
                echo "<pre>";
                print_r($d);
                echo "</pre>";
        }

        $user  = null;

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

        $user = $facebook->getUser(); // Get the UID of the connected user, or 0 if the Facebook user is not connected.  

        if(isset($_GET['code'])){
            header("Location: $RedirectUrl");
        }

        if($user == 0) {
            // If User is not connected to your app, then redirect User to Authentication Page.
         /**
          * Get a Login URL for use with redirects. By default, full page redirect is
          * assumed. If you are using the generated URL with a window.open() call in
          * JavaScript, you can pass in display=popup as part of the $params.
          * 
          * The parameters:
          * - redirect_uri: the url to go to after a successful login
          * - scope: comma separated list of requested extended perms
          */
          $login_url = $facebook->getLoginUrl($params = array('scope' => "publish_stream", 'redirect_uri' => $RedirectUrl));
          echo("<script> top.location.href='" . $login_url . "'</script>");
        } else {
            // If User is connected to your app, then do something.
            $signed_request = $facebook->getSignedRequest(); // Get the data from a signed_request token.

            $access_token = $facebook->getAccessToken(); // Determines the access token that should be used for API calls.

            $userInfo = $facebook->api("/me"); // Get's User Info

            try {
                // Posts to user's wall after the user allows your app.
                $wallpost = array(
                            'message' => "I like this",
                            'link'    => 'http://google.com',
                            'picture' => 'http://i.imgur.com/8iz6L.png',
                            'name'    => 'This is cool',
                            'description'=> 'Checkout this cool app'
                );
                $publishStream = $facebook->api("/$user/feed", "post", $wallpost); // WallPost to User's Wall using Graph API
echo "Your post was successfully posted to UID: $user";
            }
            catch (FacebookApiException $e) {
                d($e);
            } 

        }
        ?>