<?php /** * CodeIgniter * * An open source application development framework for PHP * * This content is released under the MIT License (MIT) * * Copyright (c) 2014 - 2015, British Columbia Institute of Technology * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. * * @package CodeIgniter * @author EllisLab Dev Team * @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/) * @copyright Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/) * @license http://opensource.org/licenses/MIT MIT License * @link http://codeigniter.com * @since Version 1.0.0 * @filesource */ defined('BASEPATH') OR exit('No direct script access allowed'); /** * Database Cache Class * * @category Database * @author EllisLab Dev Team * @link http://codeigniter.com/user_guide/database/ */ class CI_DB_Cache { /** * CI Singleton * * @var object */ public $CI; /** * Database object * * Allows passing of DB object so that multiple database connections * and returned DB objects can be supported. * * @var object */ public $db; // -------------------------------------------------------------------- /** * Constructor * * @param object &$db * @return void */ public 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'); $this->check_path(); } // -------------------------------------------------------------------- /** * Set Cache Directory Path * * @param string $path Path to the cache directory * @return bool */ public function check_path($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 $path = realpath($path) ? rtrim(realpath($path), DIRECTORY_SEPARATOR).DIRECTORY_SEPARATOR : rtrim($path, '/').'/'; if ( ! is_dir($path)) { log_message('debug', 'DB cache path error: '.$path); // If the path is wrong we'll turn off caching return $this->db->cache_off(); } if ( ! is_really_writable($path)) { log_message('debug', 'DB cache dir not writable: '.$path); // If the path is not really writable 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. * * @param string $sql * @return string */ public function read($sql) { $segment_one = ($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 === ($cachedata = @file_get_contents($filepath))) { return FALSE; } return unserialize($cachedata); } // -------------------------------------------------------------------- /** * Write a query to a cache file * * @param string $sql * @param object $object * @return bool */ public function write($sql, $object) { $segment_one = ($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($dir_path) && ! @mkdir($dir_path, 0750)) { return FALSE; } if (write_file($dir_path.$filename, serialize($object)) === FALSE) { return FALSE; } chmod($dir_path.$filename, 0640); return TRUE; } // -------------------------------------------------------------------- /** * Delete cache files within a particular directory * * @param string $segment_one * @param string $segment_two * @return void */ public function delete($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 * * @return void */ public function delete_all() { delete_files($this->db->cachedir, TRUE, TRUE); } }