laipower/wp-content/plugins/w3-total-cache/Cache_Base.php

227 lines
4.3 KiB
PHP

<?php
namespace W3TC;
/**
* Base cache class
*/
/**
* class Cache_Base
*/
class Cache_Base {
/*
* Blog id
*
* @var integer
*/
protected $_blog_id = 0;
/**
* To separate the caching for different modules
*
* @var string
*/
protected $_module = '';
/**
* Host
*
* @var string
*/
protected $_host = '';
/**
* Host
*
* @var int
*/
protected $_instance_id = 0;
/*
* If we are going to return expired data when some other process
* is working on new data calculation
*
* @var boolean
*/
protected $_use_expired_data = false;
/**
* Constructor
*
* @param array $config
*/
public function __construct( $config = array() ) {
$this->_blog_id = $config['blog_id'];
$this->_use_expired_data = isset( $config['use_expired_data'] )?$config['use_expired_data']:false;
$this->_module = isset( $config['module'] ) ? $config['module'] : 'default';
$this->_host = isset( $config['host'] ) ? $config['host'] : '';
$this->_instance_id = isset( $config['instance_id'] ) ? $config['instance_id'] : 0;
}
/**
* Adds data
*
* @abstract
* @param string $key
* @param mixed $data
* @param integer $expire
* @param string $group Used to differentiate between groups of cache values
* @return boolean
*/
function add( $key, &$data, $expire = 0, $group = '' ) {
return false;
}
/**
* Sets data
*
* @abstract
* @param string $key
* @param mixed $data
* @param integer $expire
* @param string $group Used to differentiate between groups of cache values
* @return boolean
*/
function set( $key, $data, $expire = 0, $group = '' ) {
return false;
}
/**
* Returns data
*
* @param string $key
* @param string $group Used to differentiate between groups of cache values
* @return mixed
*/
function get( $key, $group = '' ) {
list( $data, $has_old ) = $this->get_with_old( $key, $group );
return $data;
}
/**
* Return primary data and if old exists
*
* @abstract
* @param string $key
* @param string $group Used to differentiate between groups of cache values
* @return array|mixed
*/
function get_with_old( $key, $group = '' ) {
return array( null, false );
}
/**
* Alias for get for minify cache
*
* @param string $key
* @param string $group Used to differentiate between groups of cache values
* @return mixed
*/
function fetch( $key, $group = '' ) {
return $this->get( $key, $group = '' );
}
/**
* Replaces data
*
* @abstract
* @param string $key
* @param mixed $data
* @param integer $expire
* @param string $group Used to differentiate between groups of cache values
* @return boolean
*/
function replace( $key, &$data, $expire = 0, $group = '' ) {
return false;
}
/**
* Deletes data
*
* @abstract
* @param string $key
* @param string $group Used to differentiate between groups of cache values
* @return boolean
*/
function delete( $key, $group = '' ) {
return false;
}
/**
* Deletes primary data and old data
*
* @abstract
* @param string $key
* @return boolean
*/
function hard_delete( $key, $group = '' ) {
return false;
}
/**
* Flushes all data
*
* @abstract
* @param string $group Used to differentiate between groups of cache values
* @return boolean
*/
function flush( $group = '' ) {
return false;
}
/**
* Checks if engine can function properly in this environment
*
* @return bool
*/
public function available() {
return true;
}
/**
* Constructs key version key
*
* @param unknown $group
* @return string
*/
protected function _get_key_version_key( $group = '' ) {
return sprintf( 'w3tc_%d_%d_%s_%s_key_version',
$this->_instance_id, $this->_blog_id,
$this->_module, $group );
}
/**
* Constructs item key
*
* @param unknown $name
* @return string
*/
public function get_item_key( $name ) {
$key = sprintf( 'w3tc_%d_%s_%d_%s_%s',
$this->_instance_id, $this->_host, $this->_blog_id,
$this->_module, $name );
return $key;
}
/**
* Use key as a counter and add integet value to it
*/
public function counter_add( $key, $value ) {
return false;
}
/**
* Use key as a counter and add integet value to it
*/
public function counter_set( $key, $value ) {
return false;
}
/**
* Get counter's value
*/
public function counter_get( $key ) {
return false;
}
}