<?php
|
/**
|
* PHPIDS
|
*
|
* Requirements: PHP5, SimpleXML
|
*
|
* Copyright (c) 2008 PHPIDS group (https://phpids.org)
|
*
|
* PHPIDS 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, version 3 of the License, or
|
* (at your option) any later version.
|
*
|
* PHPIDS 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.
|
*
|
* You should have received a copy of the GNU Lesser General Public License
|
* along with PHPIDS. If not, see <http://www.gnu.org/licenses/>.
|
*
|
* PHP version 5.1.6+
|
*
|
* @category Security
|
* @package PHPIDS
|
* @author Mario Heiderich <mario.heiderich@gmail.com>
|
* @author Christian Matthies <ch0012@gmail.com>
|
* @author Lars Strojny <lars@strojny.net>
|
* @license http://www.gnu.org/licenses/lgpl.html LGPL
|
* @link http://php-ids.org/
|
*/
|
namespace IDS\Caching;
|
|
/**
|
*
|
*/
|
|
/**
|
* Database caching wrapper
|
*
|
* This class inhabits functionality to get and set cache via a database.
|
*
|
* Needed SQL:
|
*
|
|
#create the database
|
|
CREATE DATABASE IF NOT EXISTS `phpids` DEFAULT CHARACTER
|
SET utf8 COLLATE utf8_general_ci;
|
DROP TABLE IF EXISTS `cache`;
|
|
#now select the created datbase and create the table
|
|
CREATE TABLE `cache` (
|
`type` VARCHAR( 32 ) NOT null ,
|
`data` TEXT NOT null ,
|
`created` DATETIME NOT null ,
|
`modified` DATETIME NOT null
|
) ENGINE = MYISAM ;
|
*
|
* @category Security
|
* @package PHPIDS
|
* @author Christian Matthies <ch0012@gmail.com>
|
* @author Mario Heiderich <mario.heiderich@gmail.com>
|
* @author Lars Strojny <lars@strojny.net>
|
* @copyright 2007-2009 The PHPIDS Groupup
|
* @license http://www.gnu.org/licenses/lgpl.html LGPL
|
* @link http://php-ids.org/
|
* @since Version 0.4
|
*/
|
class DatabaseCache implements CacheInterface
|
{
|
|
/**
|
* Caching type
|
*
|
* @var string
|
*/
|
private $type = null;
|
|
/**
|
* Cache configuration
|
*
|
* @var array
|
*/
|
private $config = null;
|
|
/**
|
* DBH
|
*
|
* @var object
|
*/
|
private $handle = null;
|
|
/**
|
* Holds an instance of this class
|
*
|
* @var object
|
*/
|
private static $cachingInstance = null;
|
|
/**
|
* Constructor
|
*
|
* Connects to database.
|
*
|
* @param string $type caching type
|
* @param object $init the IDS_Init object
|
*
|
* @return void
|
*/
|
public function __construct($type, $init)
|
{
|
$this->type = $type;
|
$this->config = $init->config['Caching'];
|
$this->handle = $this->connect();
|
}
|
|
/**
|
* Returns an instance of this class
|
*
|
* @static
|
* @param string $type caching type
|
* @param object $init the IDS_Init object
|
*
|
* @return object $this
|
*/
|
public static function getInstance($type, $init)
|
{
|
|
if (!self::$cachingInstance) {
|
self::$cachingInstance = new DatabaseCache($type, $init);
|
}
|
|
return self::$cachingInstance;
|
}
|
|
/**
|
* Writes cache data into the database
|
*
|
* @param array $data the caching data
|
*
|
* @throws PDOException if a db error occurred
|
* @return object $this
|
*/
|
public function setCache(array $data)
|
{
|
$handle = $this->handle;
|
|
$rows = $handle->query('SELECT created FROM `' . $this->config['table'].'`');
|
|
if (!$rows || $rows->rowCount() === 0) {
|
|
$this->write($handle, $data);
|
} else {
|
|
foreach ($rows as $row) {
|
|
if ((time()-strtotime($row['created'])) >
|
$this->config['expiration_time']) {
|
|
$this->write($handle, $data);
|
}
|
}
|
}
|
|
return $this;
|
}
|
|
/**
|
* Returns the cached data
|
*
|
* Note that this method returns false if either type or file cache is
|
* not set
|
*
|
* @throws PDOException if a db error occurred
|
* @return mixed cache data or false
|
*/
|
public function getCache()
|
{
|
try {
|
$handle = $this->handle;
|
$result = $handle->prepare(
|
'SELECT * FROM `' .
|
$this->config['table'] .
|
'` where type=?'
|
);
|
$result->execute(array($this->type));
|
|
foreach ($result as $row) {
|
return unserialize($row['data']);
|
}
|
|
} catch (\PDOException $e) {
|
throw new \PDOException('PDOException: ' . $e->getMessage());
|
}
|
|
return false;
|
}
|
|
/**
|
* Connect to database and return a handle
|
*
|
* @return object PDO
|
* @throws Exception if connection parameters are faulty
|
* @throws PDOException if a db error occurred
|
*/
|
private function connect()
|
{
|
// validate connection parameters
|
if (!$this->config['wrapper']
|
|| !$this->config['user']
|
|| !$this->config['password']
|
|| !$this->config['table']) {
|
|
throw new \Exception('Insufficient connection parameters');
|
}
|
|
// try to connect
|
try {
|
$handle = new \PDO(
|
$this->config['wrapper'],
|
$this->config['user'],
|
$this->config['password']
|
);
|
$handle->setAttribute(\PDO::MYSQL_ATTR_USE_BUFFERED_QUERY, true);
|
|
} catch (\PDOException $e) {
|
throw new \PDOException('PDOException: ' . $e->getMessage());
|
}
|
|
return $handle;
|
}
|
|
/**
|
* Write the cache data to the table
|
*
|
* @param object $handle the database handle
|
* @param array $data the caching data
|
*
|
* @return object PDO
|
* @throws PDOException if a db error occurred
|
*/
|
private function write($handle, $data)
|
{
|
try {
|
$handle->query('TRUNCATE ' . $this->config['table'].'');
|
$statement = $handle->prepare(
|
'INSERT INTO `' .
|
$this->config['table'].'` (
|
type,
|
data,
|
created,
|
modified
|
)
|
VALUES (
|
:type,
|
:data,
|
now(),
|
now()
|
)'
|
);
|
|
$statement->bindValue(
|
'type',
|
$handle->quote($this->type)
|
);
|
$statement->bindValue('data', serialize($data));
|
|
if (!$statement->execute()) {
|
throw new \PDOException($statement->errorCode());
|
}
|
} catch (\PDOException $e) {
|
throw new \PDOException('PDOException: ' . $e->getMessage());
|
}
|
}
|
}
|
