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session WIP

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Qiang Xue
2013-03-03 16:51:36 -05:00
parent f68bed0ccb
commit a8a3e1a9c8
4 changed files with 532 additions and 86 deletions
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113
framework/web/CacheSession.php Normal file
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@ -0,0 +1,113 @@
<?php
/**
* DbSession class file.
*
* @link http://www.yiiframework.com/
* @copyright Copyright &copy; 2008 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
namespace yii\web;
/**
* CacheSession implements a session component using cache as storage medium.
*
* The cache being used can be any cache application component implementing {@link ICache} interface.
* The ID of the cache application component is specified via {@link cacheID}, which defaults to 'cache'.
*
* Beware, by definition cache storage are volatile, which means the data stored on them
* may be swapped out and get lost. Therefore, you must make sure the cache used by this component
* is NOT volatile. If you want to use {@link CDbCache} as storage medium, use {@link CDbHttpSession}
* is a better choice.
*
* @property boolean $useCustomStorage Whether to use custom storage.
*
* @author Qiang Xue <qiang.xue@gmail.com>
* @package system.web
* @since 1.0
*/
class CacheSession extends Session
{
/**
* Prefix to the keys for storing cached data
*/
const CACHE_KEY_PREFIX = 'Yii.CacheSession.';
/**
* @var string the ID of the cache application component. Defaults to 'cache' (the primary cache application component.)
*/
public $cacheID = 'cache';
/**
* @var ICache the cache component
*/
private $_cache;
/**
* Initializes the application component.
* This method overrides the parent implementation by checking if cache is available.
*/
public function init()
{
$this->_cache = Yii::app()->getComponent($this->cacheID);
if (!($this->_cache instanceof ICache)) {
throw new CException(Yii::t('yii', 'CacheSession.cacheID is invalid. Please make sure "{id}" refers to a valid cache application component.',
array('{id}' => $this->cacheID)));
}
parent::init();
}
/**
* Returns a value indicating whether to use custom session storage.
* This method overrides the parent implementation and always returns true.
* @return boolean whether to use custom storage.
*/
public function getUseCustomStorage()
{
return true;
}
/**
* Session read handler.
* Do not call this method directly.
* @param string $id session ID
* @return string the session data
*/
public function readSession($id)
{
$data = $this->_cache->get($this->calculateKey($id));
return $data === false ? '' : $data;
}
/**
* Session write handler.
* Do not call this method directly.
* @param string $id session ID
* @param string $data session data
* @return boolean whether session write is successful
*/
public function writeSession($id, $data)
{
return $this->_cache->set($this->calculateKey($id), $data, $this->getTimeout());
}
/**
* Session destroy handler.
* Do not call this method directly.
* @param string $id session ID
* @return boolean whether session is destroyed successfully
*/
public function destroySession($id)
{
return $this->_cache->delete($this->calculateKey($id));
}
/**
* Generates a unique key used for storing session data in cache.
* @param string $id session variable name
* @return string a safe cache key associated with the session variable name
*/
protected function calculateKey($id)
{
return self::CACHE_KEY_PREFIX . $id;
}
}

268
framework/web/DbSession.php Normal file
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@ -0,0 +1,268 @@
<?php
/**
* DbSession class file.
*
* @link http://www.yiiframework.com/
* @copyright Copyright &copy; 2008 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
namespace yii\web;
/**
* DbSession extends {@link CHttpSession} by using database as session data storage.
*
* DbSession stores session data in a DB table named 'YiiSession'. The table name
* can be changed by setting {@link sessionTableName}. If the table does not exist,
* it will be automatically created if {@link autoCreateSessionTable} is set true.
*
* The following is the table structure:
*
* <pre>
* CREATE TABLE YiiSession
* (
* id CHAR(32) PRIMARY KEY,
* expire INTEGER,
* data BLOB
* )
* </pre>
* Where 'BLOB' refers to the BLOB-type of your preffered database.
*
* DbSession relies on {@link http://www.php.net/manual/en/ref.pdo.php PDO} to access database.
*
* By default, it will use an SQLite3 database named 'session-YiiVersion.db' under the application runtime directory.
* You can also specify {@link connectionID} so that it makes use of a DB application component to access database.
*
* When using DbSession in a production server, we recommend you pre-create the session DB table
* and set {@link autoCreateSessionTable} to be false. This will greatly improve the performance.
* You may also create a DB index for the 'expire' column in the session table to further improve the performance.
*
* @property boolean $useCustomStorage Whether to use custom storage.
*
* @author Qiang Xue <qiang.xue@gmail.com>
* @package system.web
* @since 1.0
*/
class DbSession extends Session
{
/**
* @var string the ID of a {@link CDbConnection} application component. If not set, a SQLite database
* will be automatically created and used. The SQLite database file is
* is <code>protected/runtime/session-YiiVersion.db</code>.
*/
public $connectionID;
/**
* @var string the name of the DB table to store session content.
* Note, if {@link autoCreateSessionTable} is false and you want to create the DB table manually by yourself,
* you need to make sure the DB table is of the following structure:
* <pre>
* (id CHAR(32) PRIMARY KEY, expire INTEGER, data BLOB)
* </pre>
* @see autoCreateSessionTable
*/
public $sessionTableName = 'YiiSession';
/**
* @var boolean whether the session DB table should be automatically created if not exists. Defaults to true.
* @see sessionTableName
*/
public $autoCreateSessionTable = true;
/**
* @var CDbConnection the DB connection instance
*/
private $_db;
/**
* Returns a value indicating whether to use custom session storage.
* This method overrides the parent implementation and always returns true.
* @return boolean whether to use custom storage.
*/
public function getUseCustomStorage()
{
return true;
}
/**
* Updates the current session id with a newly generated one.
* Please refer to {@link http://php.net/session_regenerate_id} for more details.
* @param boolean $deleteOldSession Whether to delete the old associated session file or not.
* @since 1.1.8
*/
public function regenerateID($deleteOldSession = false)
{
$oldID = session_id();
// if no session is started, there is nothing to regenerate
if (empty($oldID)) {
return;
}
parent::regenerateID(false);
$newID = session_id();
$db = $this->getDbConnection();
$row = $db->createCommand()
->select()
->from($this->sessionTableName)
->where('id=:id', array(':id' => $oldID))
->queryRow();
if ($row !== false) {
if ($deleteOldSession) {
$db->createCommand()->update($this->sessionTableName, array(
'id' => $newID
), 'id=:oldID', array(':oldID' => $oldID));
} else {
$row['id'] = $newID;
$db->createCommand()->insert($this->sessionTableName, $row);
}
} else {
// shouldn't reach here normally
$db->createCommand()->insert($this->sessionTableName, array(
'id' => $newID,
'expire' => time() + $this->getTimeout(),
));
}
}
/**
* Creates the session DB table.
* @param CDbConnection $db the database connection
* @param string $tableName the name of the table to be created
*/
protected function createSessionTable($db, $tableName)
{
$driver = $db->getDriverName();
if ($driver === 'mysql') {
$blob = 'LONGBLOB';
} elseif ($driver === 'pgsql') {
$blob = 'BYTEA';
} else {
$blob = 'BLOB';
}
$db->createCommand()->createTable($tableName, array(
'id' => 'CHAR(32) PRIMARY KEY',
'expire' => 'integer',
'data' => $blob,
));
}
/**
* @return CDbConnection the DB connection instance
* @throws CException if {@link connectionID} does not point to a valid application component.
*/
protected function getDbConnection()
{
if ($this->_db !== null) {
return $this->_db;
} elseif (($id = $this->connectionID) !== null) {
if (($this->_db = Yii::app()->getComponent($id)) instanceof CDbConnection) {
return $this->_db;
} else {
throw new CException(Yii::t('yii', 'DbSession.connectionID "{id}" is invalid. Please make sure it refers to the ID of a CDbConnection application component.',
array('{id}' => $id)));
}
} else {
$dbFile = Yii::app()->getRuntimePath() . DIRECTORY_SEPARATOR . 'session-' . Yii::getVersion() . '.db';
return $this->_db = new CDbConnection('sqlite:' . $dbFile);
}
}
/**
* Session open handler.
* Do not call this method directly.
* @param string $savePath session save path
* @param string $sessionName session name
* @return boolean whether session is opened successfully
*/
public function openSession($savePath, $sessionName)
{
if ($this->autoCreateSessionTable) {
$db = $this->getDbConnection();
$db->setActive(true);
try {
$db->createCommand()->delete($this->sessionTableName, 'expire<:expire', array(':expire' => time()));
} catch (Exception $e) {
$this->createSessionTable($db, $this->sessionTableName);
}
}
return true;
}
/**
* Session read handler.
* Do not call this method directly.
* @param string $id session ID
* @return string the session data
*/
public function readSession($id)
{
$data = $this->getDbConnection()->createCommand()
->select('data')
->from($this->sessionTableName)
->where('expire>:expire AND id=:id', array(':expire' => time(), ':id' => $id))
->queryScalar();
return $data === false ? '' : $data;
}
/**
* Session write handler.
* Do not call this method directly.
* @param string $id session ID
* @param string $data session data
* @return boolean whether session write is successful
*/
public function writeSession($id, $data)
{
// exception must be caught in session write handler
// http://us.php.net/manual/en/function.session-set-save-handler.php
try {
$expire = time() + $this->getTimeout();
$db = $this->getDbConnection();
if ($db->createCommand()->select('id')->from($this->sessionTableName)->where('id=:id', array(':id' => $id))->queryScalar() === false) {
$db->createCommand()->insert($this->sessionTableName, array(
'id' => $id,
'data' => $data,
'expire' => $expire,
));
} else {
$db->createCommand()->update($this->sessionTableName, array(
'data' => $data,
'expire' => $expire
), 'id=:id', array(':id' => $id));
}
} catch (Exception $e) {
if (YII_DEBUG) {
echo $e->getMessage();
}
// it is too late to log an error message here
return false;
}
return true;
}
/**
* Session destroy handler.
* Do not call this method directly.
* @param string $id session ID
* @return boolean whether session is destroyed successfully
*/
public function destroySession($id)
{
$this->getDbConnection()->createCommand()
->delete($this->sessionTableName, 'id=:id', array(':id' => $id));
return true;
}
/**
* Session GC (garbage collection) handler.
* Do not call this method directly.
* @param integer $maxLifetime the number of seconds after which data will be seen as 'garbage' and cleaned up.
* @return boolean whether session is GCed successfully
*/
public function gcSession($maxLifetime)
{
$this->getDbConnection()->createCommand()
->delete($this->sessionTableName, 'expire<:expire', array(':expire' => time()));
return true;
}
}

151
framework/web/Session.php
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@ -1,15 +1,19 @@
<?php
/**
* CHttpSession class file.
* Session class file.
*
* @author Qiang Xue <qiang.xue@gmail.com>
* @link http://www.yiiframework.com/
* @copyright Copyright &copy; 2008-2011 Yii Software LLC
* @copyright Copyright &copy; 2008 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
namespace yii\web;
use yii\base\Component;
use yii\base\InvalidParamException;
/**
* CHttpSession provides session-level data management and the related configurations.
* Session provides session-level data management and the related configurations.
*
* To start the session, call {@link open()}; To complete and send out session data, call {@link close()};
* To destroy the session, call {@link destroy()}.
@ -17,9 +21,9 @@
* If {@link autoStart} is set true, the session will be started automatically
* when the application component is initialized by the application.
*
* CHttpSession can be used like an array to set and get session data. For example,
* Session can be used like an array to set and get session data. For example,
* <pre>
* $session=new CHttpSession;
* $session=new Session;
* $session->open();
* $value1=$session['name1']; // get session variable 'name1'
* $value2=$session['name2']; // get session variable 'name2'
@ -42,13 +46,13 @@
* See the corresponding setter and getter documentation for more information.
* Note, these properties must be set before the session is started.
*
* CHttpSession can be extended to support customized session storage.
* Session can be extended to support customized session storage.
* Override {@link openSession}, {@link closeSession}, {@link readSession},
* {@link writeSession}, {@link destroySession} and {@link gcSession}
* and set {@link useCustomStorage} to true.
* and set [[useCustomStorage]] to true.
* Then, the session data will be stored and retrieved using the above methods.
*
* CHttpSession is a Web application component that can be accessed via
* Session is a Web application component that can be accessed via
* {@link CWebApplication::getSession()}.
*
* @property boolean $useCustomStorage Whether to use custom storage.
@ -58,26 +62,23 @@
* @property string $savePath The current session save path, defaults to '/tmp'.
* @property array $cookieParams The session cookie parameters.
* @property string $cookieMode How to use cookie to store session ID. Defaults to 'Allow'.
* @property integer $gCProbability The probability (percentage) that the gc (garbage collection) process is started on every session initialization, defaults to 1 meaning 1% chance.
* @property float $gCProbability The probability (percentage) that the gc (garbage collection) process is started on every session initialization, defaults to 1 meaning 1% chance.
* @property boolean $useTransparentSessionID Whether transparent sid support is enabled or not, defaults to false.
* @property integer $timeout The number of seconds after which data will be seen as 'garbage' and cleaned up, defaults to 1440 seconds.
* @property CHttpSessionIterator $iterator An iterator for traversing the session variables.
* @property SessionIterator $iterator An iterator for traversing the session variables.
* @property integer $count The number of session variables.
* @property array $keys The list of session variable names.
*
* @author Qiang Xue <qiang.xue@gmail.com>
* @version $Id$
* @package system.web
* @since 1.0
* @since 2.0
*/
class CHttpSession extends CApplicationComponent implements IteratorAggregate, ArrayAccess, Countable
class Session extends Component implements \IteratorAggregate, \ArrayAccess, \Countable
{
/**
* @var boolean whether the session should be automatically started when the session application component is initialized, defaults to true.
* @var boolean whether the session should be automatically started when the session component is initialized.
*/
public $autoStart = true;
/**
* Initializes the application component.
* This method is required by IApplicationComponent and is invoked by application.
@ -93,7 +94,7 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
/**
* Returns a value indicating whether to use custom session storage.
* This method should be overriden to return true if custom session storage handler should be used.
* To use custom session storage, override this method and return This method should be overridden to return true if custom session storage handler should be used.
* If returning true, make sure the methods {@link openSession}, {@link closeSession}, {@link readSession},
* {@link writeSession}, {@link destroySession}, and {@link gcSession} are overridden in child
* class, because they will be used as the callback handlers.
@ -116,14 +117,14 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
@session_start();
if (YII_DEBUG && session_id() == '') {
$message = Yii::t('yii|Failed to start session.');
$message = Yii::t('yii', 'Failed to start session.');
if (function_exists('error_get_last')) {
$error = error_get_last();
if (isset($error['message'])) {
$message = $error['message'];
}
}
Yii::log($message, CLogger::LEVEL_WARNING, 'system.web.CHttpSession');
Yii::log($message, CLogger::LEVEL_WARNING, 'system.web.Session');
}
}
@ -216,7 +217,7 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
if (is_dir($value)) {
session_save_path($value);
} else {
throw new CException(Yii::t('yii|CHttpSession.savePath "{path}" is not a valid directory.',
throw new CException(Yii::t('yii', 'Session.savePath "{path}" is not a valid directory.',
array('{path}' => $value)));
}
}
@ -250,65 +251,65 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
}
/**
* @return string how to use cookie to store session ID. Defaults to 'Allow'.
* Returns the value indicating whether cookies should be used to store session IDs.
* @return boolean|null the value indicating whether cookies should be used to store session IDs.
* @see setUseCookies()
*/
public function getCookieMode()
public function getUseCookies()
{
if (ini_get('session.use_cookies') === '0') {
return 'none';
return false;
} elseif (ini_get('session.use_only_cookies') === '1') {
return true;
} else {
if (ini_get('session.use_only_cookies') === '0') {
return 'allow';
} else {
return 'only';
}
return null;
}
}
/**
* @param string $value how to use cookie to store session ID. Valid values include 'none', 'allow' and 'only'.
* Sets the value indicating whether cookies should be used to store session IDs.
* Three states are possible:
*
* - true: cookies and only cookies will be used to store session IDs.
* - false: cookies will not be used to store session IDs.
* - null: if possible, cookies will be used to store session IDs; if not, other mechanisms will be used (e.g. GET parameter)
*
* @param boolean|null $value the value indicating whether cookies should be used to store session IDs.
*/
public function setCookieMode($value)
public function setUseCookies($value)
{
if ($value === 'none') {
if ($value === false) {
ini_set('session.use_cookies', '0');
ini_set('session.use_only_cookies', '0');
} elseif ($value === true) {
ini_set('session.use_cookies', '1');
ini_set('session.use_only_cookies', '1');
} else {
if ($value === 'allow') {
ini_set('session.use_cookies', '1');
ini_set('session.use_only_cookies', '0');
} else {
if ($value === 'only') {
ini_set('session.use_cookies', '1');
ini_set('session.use_only_cookies', '1');
} else {
throw new CException(Yii::t('yii|CHttpSession.cookieMode can only be "none", "allow" or "only".'));
}
}
ini_set('session.use_cookies', '1');
ini_set('session.use_only_cookies', '0');
}
}
/**
* @return integer the probability (percentage) that the gc (garbage collection) process is started on every session initialization, defaults to 1 meaning 1% chance.
* @return float the probability (percentage) that the GC (garbage collection) process is started on every session initialization, defaults to 1 meaning 1% chance.
*/
public function getGCProbability()
{
return (int)ini_get('session.gc_probability');
return (float)(ini_get('session.gc_probability') / ini_get('session.gc_divisor') * 100);
}
/**
* @param integer $value the probability (percentage) that the gc (garbage collection) process is started on every session initialization.
* @throws CException if the value is beyond [0,100]
* @param float $value the probability (percentage) that the GC (garbage collection) process is started on every session initialization.
* @throws InvalidParamException if the value is not between 0 and 100.
*/
public function setGCProbability($value)
{
$value = (int)$value;
if ($value >= 0 && $value <= 100) {
ini_set('session.gc_probability', $value);
ini_set('session.gc_divisor', '100');
// percent * 21474837 / 2147483647 ≈ percent * 0.01
ini_set('session.gc_probability', floor($value * 21474836.47));
ini_set('session.gc_divisor', 2147483647);
} else {
throw new CException(Yii::t('yii|CHttpSession.gcProbability "{value}" is invalid. It must be an integer between 0 and 100.',
array('{value}' => $value)));
throw new InvalidParamException('GCProbability must be a value between 0 and 100.');
}
}
@ -329,7 +330,8 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
}
/**
* @return integer the number of seconds after which data will be seen as 'garbage' and cleaned up, defaults to 1440 seconds.
* @return integer the number of seconds after which data will be seen as 'garbage' and cleaned up.
* The default value is 1440 seconds (or the value of "session.gc_maxlifetime" set in php.ini).
*/
public function getTimeout()
{
@ -346,7 +348,7 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
/**
* Session open handler.
* This method should be overridden if {@link useCustomStorage} is set true.
* This method should be overridden if [[useCustomStorage]] is set true.
* Do not call this method directly.
* @param string $savePath session save path
* @param string $sessionName session name
@ -359,7 +361,7 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
/**
* Session close handler.
* This method should be overridden if {@link useCustomStorage} is set true.
* This method should be overridden if [[useCustomStorage]] is set true.
* Do not call this method directly.
* @return boolean whether session is closed successfully
*/
@ -370,7 +372,7 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
/**
* Session read handler.
* This method should be overridden if {@link useCustomStorage} is set true.
* This method should be overridden if [[useCustomStorage]] is set true.
* Do not call this method directly.
* @param string $id session ID
* @return string the session data
@ -382,7 +384,7 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
/**
* Session write handler.
* This method should be overridden if {@link useCustomStorage} is set true.
* This method should be overridden if [[useCustomStorage]] is set true.
* Do not call this method directly.
* @param string $id session ID
* @param string $data session data
@ -395,7 +397,7 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
/**
* Session destroy handler.
* This method should be overridden if {@link useCustomStorage} is set true.
* This method should be overridden if [[useCustomStorage]] is set true.
* Do not call this method directly.
* @param string $id session ID
* @return boolean whether session is destroyed successfully
@ -407,7 +409,7 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
/**
* Session GC (garbage collection) handler.
* This method should be overridden if {@link useCustomStorage} is set true.
* This method should be overridden if [[useCustomStorage]] is set true.
* Do not call this method directly.
* @param integer $maxLifetime the number of seconds after which data will be seen as 'garbage' and cleaned up.
* @return boolean whether session is GCed successfully
@ -417,16 +419,14 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
return true;
}
//------ The following methods enable CHttpSession to be CMap-like -----
/**
* Returns an iterator for traversing the session variables.
* This method is required by the interface IteratorAggregate.
* @return CHttpSessionIterator an iterator for traversing the session variables.
* @return SessionIterator an iterator for traversing the session variables.
*/
public function getIterator()
{
return new CHttpSessionIterator;
return new SessionIterator;
}
/**
@ -448,39 +448,18 @@ class CHttpSession extends CApplicationComponent implements IteratorAggregate, A
return $this->getCount();
}
/**
* @return array the list of session variable names
*/
public function getKeys()
{
return array_keys($_SESSION);
}
/**
* Returns the session variable value with the session variable name.
* This method is very similar to {@link itemAt} and {@link offsetGet},
* except that it will return $defaultValue if the session variable does not exist.
* @param mixed $key the session variable name
* If the session variable does not exist, the `$defaultValue` will be returned.
* @param string $key the session variable name
* @param mixed $defaultValue the default value to be returned when the session variable does not exist.
* @return mixed the session variable value, or $defaultValue if the session variable does not exist.
* @since 1.1.2
*/
public function get($key, $defaultValue = null)
{
return isset($_SESSION[$key]) ? $_SESSION[$key] : $defaultValue;
}
/**
* Returns the session variable value with the session variable name.
* This method is exactly the same as {@link offsetGet}.
* @param mixed $key the session variable name
* @return mixed the session variable value, null if no such variable exists
*/
public function itemAt($key)
{
return isset($_SESSION[$key]) ? $_SESSION[$key] : null;
}
/**
* Adds a session variable.
* Note, if the specified name already exists, the old value will be removed first.

86
framework/web/SessionIterator.php Normal file
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@ -0,0 +1,86 @@
<?php
/**
* SessionIterator class file.
*
* @link http://www.yiiframework.com/
* @copyright Copyright &copy; 2008 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
namespace yii\web;
/**
* SessionIterator implements an iterator for traversing session variables managed by [[Session]].
*
* @author Qiang Xue <qiang.xue@gmail.com>
* @since 2.0
*/
class SessionIterator implements \Iterator
{
/**
* @var array list of keys in the map
*/
private $_keys;
/**
* @var mixed current key
*/
private $_key;
/**
* Constructor.
*/
public function __construct()
{
$this->_keys = array_keys($_SESSION);
}
/**
* Rewinds internal array pointer.
* This method is required by the interface Iterator.
*/
public function rewind()
{
$this->_key = reset($this->_keys);
}
/**
* Returns the key of the current array element.
* This method is required by the interface Iterator.
* @return mixed the key of the current array element
*/
public function key()
{
return $this->_key;
}
/**
* Returns the current array element.
* This method is required by the interface Iterator.
* @return mixed the current array element
*/
public function current()
{
return isset($_SESSION[$this->_key]) ? $_SESSION[$this->_key] : null;
}
/**
* Moves the internal pointer to the next array element.
* This method is required by the interface Iterator.
*/
public function next()
{
do {
$this->_key = next($this->_keys);
} while (!isset($_SESSION[$this->_key]) && $this->_key !== false);
}
/**
* Returns whether there is an element at current position.
* This method is required by the interface Iterator.
* @return boolean
*/
public function valid()
{
return $this->_key !== false;
}
}