<?php
/**
* @brief Abstract Storage Class
* @author <a href='https://www.invisioncommunity.com'>Invision Power Services, Inc.</a>
* @copyright (c) Invision Power Services, Inc.
* @license https://www.invisioncommunity.com/legal/standards/
* @package Invision Community
* @since 07 May 2013
*/
namespace IPS\Data;
/* To prevent PHP errors (extending class does not exist) revealing path */
if ( !defined( '\IPS\SUITE_UNIQUE_KEY' ) )
{
header( ( isset( $_SERVER['SERVER_PROTOCOL'] ) ? $_SERVER['SERVER_PROTOCOL'] : 'HTTP/1.0' ) . ' 403 Forbidden' );
exit;
}
/**
* Abstract Storage Class
*/
abstract class _Store extends AbstractData
{
/**
* @brief Instance
*/
protected static $instance;
/**
* Get instance
*
* @return \IPS\Data\Store
*/
public static function i()
{
if( static::$instance === NULL )
{
$classname = 'IPS\Data\Store\\' . \IPS\STORE_METHOD;
static::$instance = new $classname( json_decode( \IPS\STORE_CONFIG, TRUE ) );
}
return static::$instance;
}
/**
* @brief Always needed Store keys
*/
public $initLoad = array();
/**
* @brief Template store keys
*/
public $templateLoad = array();
/**
* @brief Log
*/
public $log = array();
/**
* Load mutiple
* Used so if it is known that several are going to be needed, they can all be loaded into memory at the same time
*
* @param array $keys Keys
* @return void
*/
public function loadIntoMemory( array $keys )
{
}
/**
* Test the datastore engine to make sure it's working
*
* @return bool
*/
public function test()
{
/* Set a test key */
$key = 'test_' . md5( mt_rand() );
$this->$key = '1';
/* Now clear our internal cache to ensure the value isn't returned from there */
unset( $this->_data[ $key ], $this->_exists[ $key ], static::$cache[ $key ] );
/* And then try to retrieve it */
if( isset( $this->$key ) )
{
$value = $this->$key;
unset( $this->$key );
return ( $value == 1 ) ? TRUE : FALSE;
}
return FALSE;
}
/**
* Magic Method: Get
*
* @param string $key Key
* @return string Value from the _datastore
*/
public function __get( $key )
{
/* Try to get it from the cache store... */
try
{
/* If caching is enabled, and this isn't the special map of hashes... */
if ( $this->useCache( $key ) )
{
if ( \IPS\Data\Cache::i()->checkKeys() === false )
{
if ( isset( \IPS\Data\Cache::i()->$key ) and \IPS\Data\Cache::i()->$key !== NULL )
{
/* Cache engine always returns current content, so return it */
return \IPS\Data\Cache::i()->$key;
}
/* Still here? throw an exception so we get it from the data storage engine */
throw new \OutOfRangeException;
}
else
{
/* It exists in the caching engine, and we know the hash of the correct value... */
$cacheKeys = ( isset( $this->cacheKeys ) and is_array( $this->cacheKeys ) ) ? $this->cacheKeys : array();
if ( array_key_exists( $key, $cacheKeys ) and isset( \IPS\Data\Cache::i()->$key ) )
{
/* Get it... */
$value = \IPS\Data\Cache::i()->$key;
/* But only use it if the hash matches */
if( $cacheKeys[ $key ] == md5( json_encode( $value ) ) )
{
return $value;
}
}
}
}
/* Still here? throw an exception so we get it from the data storage engine */
throw new \OutOfRangeException;
}
/* If we couldn't get it from the cache engine, get it from the data storage engine */
catch ( \OutOfRangeException $e )
{
/* Actually get it... */
$value = parent::__get( $key );
/* If caching is enabled, and this isn't the special map of hashes... */
if ( $this->useCache( $key ) )
{
/* Set it in the caching engine... */
\IPS\Data\Cache::i()->$key = $value;
if ( \IPS\Data\Cache::i()->checkKeys() === true )
{
/* And set the hash in the cacheKeys hash map */
$cacheKeys = ( isset( $this->cacheKeys ) and is_array( $this->cacheKeys ) ) ? $this->cacheKeys : array();
$cacheKeys[ $key ] = md5( json_encode( $value ) );
$this->cacheKeys = $cacheKeys;
}
}
return $value;
}
}
/**
* Magic Method: Set
*
* @param string $key Key
* @param string $value Value
* @return void
*/
public function __set( $key, $value )
{
/* Actually set it in the data storage engine */
parent::__set( $key, $value );
/* If caching is enabled, and this isn't the special map of hashes... */
if ( $this->useCache( $key ) )
{
/* Then also set it in the cache... */
\IPS\Data\Cache::i()->$key = $value;
/* And set the hash in the cacheKeys hash map */
if ( \IPS\Data\Cache::i()->checkKeys() === true )
{
if ( ( isset( $this->cacheKeys ) and is_array( $this->cacheKeys ) ) )
{
$cacheKeys = is_array( $this->cacheKeys ) ? $this->cacheKeys : array();
$cacheKeys[ $key ] = md5( json_encode( $value ) );
$this->cacheKeys = $cacheKeys;
}
else
{
$this->cacheKeys = array( $key => md5( json_encode( $value ) ) );
}
}
}
}
/**
* Magic Method: Isset
*
* @param string $key Key
* @return bool
*/
public function __isset( $key )
{
/* If caching is enabled, and this isn't the special map of hashes, try to get it from the cache store... */
if ( $this->useCache( $key ) )
{
/* Does it exist in the caching engine? */
if ( isset( \IPS\Data\Cache::i()->$key ) )
{
/* Get it... */
$value = \IPS\Data\Cache::i()->$key;
if ( \IPS\Data\Cache::i()->checkKeys() === false )
{
/* Cache engine always returns current content, so return it */
return TRUE;
}
/* Only use it if the hash matches */
$cacheKeys = ( isset( $this->cacheKeys ) and is_array( $this->cacheKeys ) ) ? $this->cacheKeys : array();
if ( isset( $cacheKeys[ $key ] ) and $cacheKeys[ $key ] == md5( json_encode( $value ) ) )
{
return TRUE;
}
}
}
/* If we're still here, check the data storage engine... */
return parent::__isset( $key );
}
/**
* Magic Method: Unset
*
* @param string $key Key
* @return void
*/
public function __unset( $key )
{
/* Unset it in the data storage engine */
parent::__unset( $key );
/* If caching is enabled, and this isn't the special map of hashes, remove it from the cache store... */
if ( $this->useCache( $key ) )
{
/* Remove it from the cache store... */
unset( \IPS\Data\Cache::i()->$key );
if ( \IPS\Data\Cache::i()->checkKeys() === true )
{
/* And from the special map of hashes */
try
{
$cacheKeys = is_array( $this->cacheKeys ) ? $this->cacheKeys : array();
}
/* If the cache doesn't exist we shouldn't error out with an uncaught OutOfRangeException */
catch( \OutOfRangeException $e )
{
$cacheKeys = array();
}
if( isset( $cacheKeys[ $key ] ) )
{
unset( $cacheKeys[ $key ] );
}
$this->cacheKeys = $cacheKeys;
}
}
}
/**
* Check the cache for this key?
*
* @param string $key The store key
* @return boolean
*/
protected function useCache( $key )
{
return ( \IPS\CACHE_METHOD != \IPS\STORE_METHOD and ( ! \IPS\Data\Cache::i() instanceof \IPS\Data\Cache\None ) and $key !== 'cacheKeys' );
}
}