/system/database/DB_cache.php
PHP | 195 lines | 79 code | 33 blank | 83 comment | 21 complexity | 9aadfbd649b6922c6707db3fa3197c90 MD5 | raw file
Possible License(s): GPL-3.0, LGPL-2.1, GPL-2.0
- <?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
- /**
- * CodeIgniter
- *
- * An open source application development framework for PHP 5.1.6 or newer
- *
- * @package CodeIgniter
- * @author ExpressionEngine Dev Team
- * @copyright Copyright (c) 2008 - 2011, EllisLab, Inc.
- * @license http://codeigniter.com/user_guide/license.html
- * @link http://codeigniter.com
- * @since Version 1.0
- * @filesource
- */
- // ------------------------------------------------------------------------
- /**
- * Database Cache Class
- *
- * @category Database
- * @author ExpressionEngine Dev Team
- * @link http://codeigniter.com/user_guide/database/
- */
- class CI_DB_Cache {
- var $CI;
- var $db; // allows passing of db object so that multiple database connections and returned db objects can be supported
- /**
- * Constructor
- *
- * Grabs the CI super object instance so we can access it.
- *
- */
- function __construct(&$db)
- {
- // Assign the main CI object to $this->CI
- // and load the file helper since we use it a lot
- $this->CI =& get_instance();
- $this->db =& $db;
- $this->CI->load->helper('file');
- }
- // --------------------------------------------------------------------
- /**
- * Set Cache Directory Path
- *
- * @access public
- * @param string the path to the cache directory
- * @return bool
- */
- function check_path($path = '')
- {
- if ($path == '')
- {
- if ($this->db->cachedir == '')
- {
- return $this->db->cache_off();
- }
- $path = $this->db->cachedir;
- }
- // Add a trailing slash to the path if needed
- $path = preg_replace("/(.+?)\/*$/", "\\1/", $path);
- if ( ! is_dir($path) OR ! is_really_writable($path))
- {
- // If the path is wrong we'll turn off caching
- return $this->db->cache_off();
- }
- $this->db->cachedir = $path;
- return TRUE;
- }
- // --------------------------------------------------------------------
- /**
- * Retrieve a cached query
- *
- * The URI being requested will become the name of the cache sub-folder.
- * An MD5 hash of the SQL statement will become the cache file name
- *
- * @access public
- * @return string
- */
- function read($sql)
- {
- if ( ! $this->check_path())
- {
- return $this->db->cache_off();
- }
- $segment_one = ($this->CI->uri->segment(1) == FALSE) ? 'default' : $this->CI->uri->segment(1);
- $segment_two = ($this->CI->uri->segment(2) == FALSE) ? 'index' : $this->CI->uri->segment(2);
- $filepath = $this->db->cachedir.$segment_one.'+'.$segment_two.'/'.md5($sql);
- if (FALSE === ($cachedata = read_file($filepath)))
- {
- return FALSE;
- }
- return unserialize($cachedata);
- }
- // --------------------------------------------------------------------
- /**
- * Write a query to a cache file
- *
- * @access public
- * @return bool
- */
- function write($sql, $object)
- {
- if ( ! $this->check_path())
- {
- return $this->db->cache_off();
- }
- $segment_one = ($this->CI->uri->segment(1) == FALSE) ? 'default' : $this->CI->uri->segment(1);
- $segment_two = ($this->CI->uri->segment(2) == FALSE) ? 'index' : $this->CI->uri->segment(2);
- $dir_path = $this->db->cachedir.$segment_one.'+'.$segment_two.'/';
- $filename = md5($sql);
- if ( ! @is_dir($dir_path))
- {
- if ( ! @mkdir($dir_path, DIR_WRITE_MODE))
- {
- return FALSE;
- }
- @chmod($dir_path, DIR_WRITE_MODE);
- }
- if (write_file($dir_path.$filename, serialize($object)) === FALSE)
- {
- return FALSE;
- }
- @chmod($dir_path.$filename, FILE_WRITE_MODE);
- return TRUE;
- }
- // --------------------------------------------------------------------
- /**
- * Delete cache files within a particular directory
- *
- * @access public
- * @return bool
- */
- function delete($segment_one = '', $segment_two = '')
- {
- if ($segment_one == '')
- {
- $segment_one = ($this->CI->uri->segment(1) == FALSE) ? 'default' : $this->CI->uri->segment(1);
- }
- if ($segment_two == '')
- {
- $segment_two = ($this->CI->uri->segment(2) == FALSE) ? 'index' : $this->CI->uri->segment(2);
- }
- $dir_path = $this->db->cachedir.$segment_one.'+'.$segment_two.'/';
- delete_files($dir_path, TRUE);
- }
- // --------------------------------------------------------------------
- /**
- * Delete all existing cache files
- *
- * @access public
- * @return bool
- */
- function delete_all()
- {
- delete_files($this->db->cachedir, TRUE);
- }
- }
- /* End of file DB_cache.php */
- /* Location: ./system/database/DB_cache.php */