Session handler

Kode 

<?php
/**
 * Project:		Blob: Core engine
 * File:        session.php
 *
 * This code is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This code is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * @link http://www.blobmedia.dk/
 * @copyright 2008 Blob Media
 * @author Michael Larsen <ml at blobmedia dot dk>
 * @package Blob
 * @version 1.0
 */
 
/**
 * Handles sessions in a more fasionable way.
 * @package Blob
 * @class Session
 */
class Session
{
	/**
	 * @cfg {string} $namespace Namespace for locating session data
	 */
	private $namespace;
	
	/**
	 * @cfg {boolean} $autoCreate Auto create session namespace if
	 * it does not exist. Defaults to true.
	 */		
	private $autoCreate = true;

	/**
	 * @cfg {boolean} $throwErrors True to allow throwing exceptions
	 * caused by class. Defaults to true.
	 */		
	private $throwErrors = true;

	/**
	 * Data container.
	 */
	private $data = NULL;
	
	/**
	 * The class constructor
	 */
	function __construct(array $config = array()) {
		if(!$_SESSION) {
			@session_start();
		}
		
		// Security checks
		if (!isset($_SESSION['initiated'])) {
			session_regenerate_id();
			$_SESSION['initiated'] = true;
		}
		
		if (isset($_SESSION['HTTP_USER_AGENT'])) {
			if ($_SESSION['HTTP_USER_AGENT'] != md5($_SERVER['HTTP_USER_AGENT'])) {
				die('Invalid user access');
			}
		} else {
			$_SESSION['HTTP_USER_AGENT'] = md5($_SERVER['HTTP_USER_AGENT']);
		}
		
		if(empty($config['namespace']) && !in_array($config['namespace'],array('initiated','HTTP_USER_AGENT'))) {
			if($this->throwErrors !== true) {
				throw new SessionException('Could not create session, namespace not valid.');
			} else {
				return;
			}
		}
		
		$this->namespace = $config['namespace'];
		
		if(!$this->exists()) {
			$_SESSION[$this->namespace] = array();
		}
		
		$this->data = $_SESSION[$this->namespace];
		unset($_SESSION[$this->namespace]);
	}
	
	/**
	 * The class destructor
	 */		
	function __destruct() {
		if($this->data) {
			$_SESSION[$this->namespace] = $this->data;
		}
	}
	
	/**
	 * MAGIC getter
	 */
	function __get($name) {
		if(!$this->exists($this->autoCreate)) {
			if($this->throwErrors !== true) {
				throw new SessionException('Could not get variable, session does not exist.');
			} else {
				return NULL;
			}
		}
		
		return $this->data[$name];
	}
	
	/**
	 * MAGIC setter
	 */
	function __set($name,$val) {
		if(!$this->exists($this->autoCreate)) {
			if($this->throwErrors !== true) {
				throw new SessionException('Could not set variable, session does not exist.');
			} else {
				return NULL;
			}
		}
		
		$this->data[$name] = $val;
		return $val;
	}
	
	/**
	 * Return true if session of namespace exists.
	 * @param {boolean} $autoCreate True to automatically create session namespace if it does not exist.
	 */
	function exists($autoCreate = false) {
		if($this->namespace) {
			if($autoCreate === true) {
				$_SESSION[$this->namespace] = array();
			}
			if(isset($_SESSION[$this->namespace])) {
				return true;
			}
		}
		return false;
	}

	/**
	 * Loads an array of values into the session
	 * @param {array} $array Array of values
	 */
	function load(array $array) {
		unset($array['namespace']);
		
		foreach($array as $name => $val) {
			$this->data[$name] = $val;
		}
	}
	
	/**
	 * Removes the whole session
	 */
	function remove() {
		if(!$this->exists()) {
			if($this->throwErrors !== true) {
				throw new SessionException('Could not remove session, session does not exist.');
			} else {
				return false;
			}
		}
	
		$_SESSION[$this->namespace] = NULL;
		unset($_SESSION[$this->namespace]);
		
		$this->data = NULL;
		
		return true;
	}
}

/**
 * Rewrites common exception output
 * @package Blob
 * @class SessionException
 */
class SessionException extends Exception
{
	// Redefine the exception so error message isn't optional
	public function __construct($message, $code = 0) {
		// make sure everything is assigned properly
		parent::__construct($message, $code);
	}
	
	// custom string representation of object
	public function __toString() {
		return get_class($this) . ": [{$this->code}]: {$this->message}\\n";
	}
}
?>

Kode 

<?php
	$session = new Session(array('namespace'=>'saveNamespace'));
	$session->name = 'Blob'
	
	print $session->name;
?>