Facebook connect by CApplicationComponent

FacebookConnect.php

<?php
/**
 * FacebookConnect class file.
 * @author Christoffer Niska <ChristofferNiska@gmail.com>
 * @copyright Copyright &copy; Christoffer Niska 2011-
 * @license http://www.opensource.org/licenses/bsd-license.php New BSD License
 */

/**
 * Facebook connection application component.
 */
require(dirname(__FILE__) . '/../../vendors/facebook/facebook.php'); // Yii::import() will not work in this case
class FacebookConnect extends CApplicationComponent
{
        /**
         * @property string Facebook application id.
         */
        public $appId;
        /**
         * @property string Facebook application secret.
         */
        public $appSecret;
        /**
         * @property string the application namespace.
         */
        public $appNamespace;
        /**
         * @property boolean whether file uploads are enabled.
         */
        public $fileUpload;

        protected $_userId;
        protected $_facebook;

        /**
         * Initializes this component.
         */
        public function init()
        {
                $config = array(
                        'appId' => $this->appId,
                        'secret' => $this->appSecret
                );

                if ($this->fileUpload !== null)
                        $config['fileUpload'] = $this->fileUpload;

                $this->_facebook = new Facebook($config);

                parent::init();
        }

        /**
         * Logs in the current user using facebook.
         * @return boolean whether the user was logged in successfully
         */
        public function login()
        {
                $profile = $this->api('me');
                $user = User::model()->findByAttributes(array('email'=>$profile['email']));

                if (!empty($profile))
                {
                        if ($user === null)
                        {
                                $user = new User();
                                $user->name = $profile['username'];
                                $user->email = $profile['email'];
                                $user->fbuid = $profile['id'];
                                $user->status = User::STATUS_ACTIVATED;
                                $user->activated = new CDbExpression('NOW()');
                        }

                        $user->save(false);
                }

                if ($user !== null)
                {
                        // NOTE: Facebook users are not authenticated using a password
                        // so we can simply generate a random one to prevent misuse.
                        $identity = new UserIdentity($user->name, $user->password);
                        $identity->authenticate(UserIdentity::AUTH_TYPE_FACEBOOK);

                        if ((int) $identity->errorCode === UserIdentity::ERROR_NONE)
                        {
                                $duration = 3600 * 24 * 30; // 30 days
                                Yii::app()->user->login($identity, $duration);
                                return true;
                        }
                }

                return false;
        }

        /**
         * Registers an Open Graph action with Facebook.
         * @param string $action the action to register.
         * @param array $params the query parameters.
         */
        public function registerAction($action, $params=array())
        {
                if (!isset($params['access_token']))
                        $params['access_token'] = $this->facebook->getAccessToken();

                $this->api('me/'.$this->appNamespace.':'.$action, $params);
        }
        
        /**
         * Returns the model for the currently logged in Facebook user.
         * @return User the user model.
         */
        public function loadUser()
        {
                $fbuid = $this->getUserId();
                return $fbuid > 0 ? User::model()->findByAttributes(array('fbuid'=>$fbuid)) : null;
        }

        /**
         * @return integer the Facebook user id.
         */
        public function getUserId()
        {
                if ($this->_userId !== null)
                        return $this->_userId;
                else
                {
                        $userId = 0;

                        try
                        {
                                $userId = $this->_facebook->getUser();
                        }
                        catch (FacebookApiException $e)
                        {
                        }

                        return $this->_userId = $userId;
                }
        }

        /**
         * Calls the Facebook API.
         * @param string $query the query to send.
         * @param array $params the query paramters.
         * @return array the response.
         */
        public function api($query, $params=array())
        {
                $data = array();

                if (!empty($params))
                        $query .= '?'.http_build_query($params);

                try
                {
                        $data = $this->_facebook->api('/'.$query);
                }
                catch (FacebookApiException $e)
                {
                }

                return $data;
        }

        /**
         * @return Facebook the Facebook application instance.
         */
        public function getFacebook()
        {
                return $this->_facebook;
        }
}
?>

UserIdentity.php

<?php
/**
 * UserIdentity class file.
 * @author Christoffer Niska <ChristofferNiska@gmail.com>
 * @copyright Copyright &copy; Christoffer Niska 2011-
 * @license http://www.opensource.org/licenses/bsd-license.php New BSD License
 */

class UserIdentity extends CUserIdentity
{
        const AUTH_TYPE_DATABASE = 1;
        const AUTH_TYPE_FACEBOOK = 2;

        const ERROR_STATUS_INVALID = 10;

        private $_id;

        /**
         * Authenticates a user.
         * @param integer $type the authentication type, defaults to database.
         * @return boolean whether authentication succeeds.
         */
        public function authenticate($type = self::AUTH_TYPE_DATABASE)
        {
                switch ($type)
                {
                        // Facebook authentication
                        case self::AUTH_TYPE_FACEBOOK:
                                $user = Yii::app()->fb->loadUser();

                                if ($user === null)
                                        $this->errorCode = self::ERROR_USERNAME_INVALID;
                                else if ((int) $user->status !== User::STATUS_ACTIVATED)
                                        $this->errorCode = self::ERROR_STATUS_INVALID;
                                else
                                {
                                        $this->_id = $user->id;
                                        $this->username = $user->name;
                                        $this->setState('fbuid',$user->fbuid);
                                        $this->setState('isAdmin', $user->admin);
                                        $this->errorCode = self::ERROR_NONE;
                                }

                                break;

                        // Default authentication (name, status, password)
                        case self::AUTH_TYPE_DATABASE:
                        default:
                                /** @var User $user */
                                $user = User::model()->find('LOWER(name)=?', array(strtolower($this->username)));

                                if ($user === null)
                                        $this->errorCode = self::ERROR_USERNAME_INVALID;
                                else if (!$user->validatePassword($this->password))
                                        $this->errorCode = self::ERROR_PASSWORD_INVALID;
                                else if ((int) $user->status !== User::STATUS_ACTIVATED)
                                        $this->errorCode = self::ERROR_STATUS_INVALID;
                                else
                                {
                                        $this->_id = $user->id;
                                        $this->username = $user->name;
                                        $this->setState('isAdmin', $user->admin);
                                        $this->errorCode = self::ERROR_NONE;
                                }

                                break;
                }

                return $this->errorCode == self::ERROR_NONE;
        }

        /**
         * @return integer the ID of the user record
         */
        public function getId()
        {
                return $this->_id;
        }
}
?>