Scriptte facebook ile login olmaya çalıştığımda aldığım hata aşağıdaki gibidir.

Warning: PDOStatement::execute(): SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'mail' cannot be null in /home3/zuhurat/public_html/modules/session/fb_login.php on line 135

Warning: Cannot modify header information - headers already sent by (output started at /home3/zuhurat/public_html/modules/session/fb_login.php:135) in /home3/zuhurat/public_html/modules/session/fb_login.php on line 154

fb_login.php dosyam iste aşağıdaki gibidir.

<?php

session_start();

require_once app_base_path('/thirdparty/Facebook/FacebookSession.php');
require_once app_base_path('/thirdparty/Facebook/FacebookRedirectLoginHelper.php');
require_once app_base_path('/thirdparty/Facebook/FacebookCanvasLoginHelper.php');
require_once app_base_path('/thirdparty/Facebook/FacebookJavaScriptLoginHelper.php');
require_once app_base_path('/thirdparty/Facebook/FacebookRequest.php');
require_once app_base_path('/thirdparty/Facebook/FacebookResponse.php');
require_once app_base_path('/thirdparty/Facebook/FacebookSDKException.php');
require_once app_base_path('/thirdparty/Facebook/FacebookRequestException.php');
require_once app_base_path('/thirdparty/Facebook/FacebookAuthorizationException.php');
require_once app_base_path('/thirdparty/Facebook/GraphObject.php');
require_once app_base_path('/thirdparty/Facebook/HttpClients/FacebookCurl.php');
require_once app_base_path('/thirdparty/Facebook/HttpClients/FacebookHttpable.php');
require_once app_base_path('/thirdparty/Facebook/HttpClients/FacebookCurlHttpClient.php');
require_once app_base_path('/thirdparty/Facebook/GraphUser.php');

use Facebook\FacebookSession;
use Facebook\FacebookRedirectLoginHelper;
use Facebook\FacebookCanvasLoginHelper;
use Facebook\FacebookJavaScriptLoginHelper;
use Facebook\FacebookRequest;
use Facebook\FacebookResponse;
use Facebook\FacebookSDKException;
use Facebook\FacebookRequestException;
use Facebook\FacebookAuthorizationException;
use Facebook\GraphObject;
use Facebook\HttpClients\FacebookCurl;
use Facebook\HttpClients\FacebookHttpable;
use Facebook\HttpClients\FacebookCurlHttpClient;
use Facebook\GraphUser;

Facebook\FacebookSession::setDefaultApplication('1699101090323930','97727af42e8d6df6197e2d8cb6c28f10');
$helper = new Facebook\FacebookRedirectLoginHelper(full_uri('fb-login'));

if (isset($_REQUEST['code'])) {
    try {
        $session = $helper->getSessionFromRedirect();
    } catch(FacebookRequestException $ex) {
        
    } catch(\Exception $ex) {
        
    }

    if (isset($session)) {
        if (!$session) {
            header('Location: '.full_uri('main'));
            exit;
        }
        
        $fb_user = (new FacebookRequest(
            $session, 'GET', '/me'
        ))->execute()->getGraphObject(GraphUser::className())->asArray();
        
        $fb_avatar_url = (new FacebookRequest(
            $session, 'GET', '/me/picture?redirect=false&width=150&height=150'
        ))->execute()->getGraphObject(GraphUser::className())->asArray()['url'];
        
        global $database;
        connect_database();
        
        ob_start();
        ?>
        select
            *
        from
            users
        where
            mail = ?
        <?php
        $query = ob_get_clean();
        $query = $database->prepare($query);
        $query->execute(array($fb_user['email']));
        $user_from_fb = $query->fetch();
        
        if (!$user_from_fb) {
            $user_uniqid = uniqid();
            if ($fb_avatar_url) {
                $avatar_file_name = $user_uniqid.'.jpg';
                file_put_contents(
                    static_path('/images/'.$avatar_file_name),
                    file_get_contents($fb_avatar_url)
                );
            } else {
                $avatar_file_name = '';
            }

            ob_start();
            ?>
            insert
                into
                    users
                (
                    namespace,
                    fb_id,
                    mail,
                    user_name,
                    avatar,
                    password,
                    name,
                    `source`,
                    added_time,
                    updated_time,
                    record_order
                )
                values (
                    :namespace,
                    :fb_id,
                    :mail,
                    :user_name,
                    :avatar,
                    :password,
                    :name,
                    <?php echo USER_SOURCE_FACEBOOK; ?>,
                    NOW(),
                    NOW(),
                    <?php echo time(); ?>
                )
            <?php
            $query = ob_get_clean();
            $query = $database->prepare($query);

            $user_name = 'yazar'.$user_uniqid;
            $user_namespace = sef_url($user_name);

            $query->bindParam(':namespace', $user_namespace, PDO::PARAM_STR);
            $query->bindParam(':fb_id', $fb_user['id'], PDO::PARAM_STR);
            $query->bindParam(':mail', $fb_user['email'], PDO::PARAM_STR);
            $query->bindParam(':user_name', $user_name, PDO::PARAM_STR);
            $query->bindParam(':avatar', $avatar_file_name, PDO::PARAM_STR);
            $query->bindValue(':password', '', PDO::PARAM_STR);
            $query->bindParam(':name', $fb_user['name'], PDO::PARAM_STR);
            $query->execute();

            $_SESSION[SESSION_INDEX]['user'] = array(
                'id'=>$database->lastInsertId(),
                'fb_id'=>$fb_user['id'],
                'namespace'=>$user_namespace,
                'mail'=>$fb_user['email'],
                'user_name'=>$user_name,
                'avatar'=>$avatar_file_name,
                'name'=>$fb_user['name'],
                'source'=>USER_SOURCE_FACEBOOK,
                'count_news'=>0,
                'count_news_accepted'=>0,
                'count_news_rejected'=>0,
                'count_news_waiting'=>0,
                'count_comments'=>0,
                'count_comments_accepted'=>0,
            );
            
            header('Location: '.full_uri('main'));
        } else {
            $_SESSION[SESSION_INDEX]['user'] = $user_from_fb;
            header('Location: '.full_uri('main'));
        }
    } else {
        header('Location: '.full_uri('main'));
    }
} else{
    $fb_login_url = $helper->getLoginUrl(array('email'));
    header('Location: '.$fb_login_url);
}

?>

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