shindig的缓存类和apc缓存类实现

 

 

<?phpclass CacheException extends Exception {}/** * 缓存抽象类 */abstract class Cache_Abstract {/** * 读缓存变量 * * @param string $key 缓存下标 * @return mixed */ abstract public function fetch($key);/** * 缓存变量 * * @param string $key 缓存变量下标 * @param string $value 缓存变量的值 * @return bool */ abstract public function store($key, $value);/** * 删除缓存变量 * * @param string $key 缓存下标 * @return Cache_Abstract */ abstract public function delete($key);/** * 清(删)除所有缓存 * * @return Cache_Abstract */ abstract public function clear();/** * 锁定缓存变量 * * @param string $key 缓存下标 * @return Cache_Abstract */ abstract public function lock($key);/** * 缓存变量解锁 * * @param string $key 缓存下标 * @return Cache_Abstract */ abstract public function unlock($key);/** * 取得缓存变量是否被锁定 * * @param string $key 缓存下标 * @return bool */ abstract public function isLocked($key);/** * 确保不是锁定状态 * 最多做$tries次睡眠等待解锁，超时则跳过并解锁 * * @param string $key 缓存下标 */ public function checkLock($key) { if (!$this->isLocked($key)) { return $this; } $tries = 10; $count = 0; do { usleep(200); $count ++; } while ($count <= $tries && $this->isLocked($key)); // 最多做十次睡眠等待解锁，超时则跳过并解锁 $this->isLocked($key) && $this->unlock($key); return $this; }}/** * APC扩展缓存实现 * * * @category Mjie * @package Cache * @author 流水孟春 * @copyright Copyright (c) 2008- <cmpan(at)qq.com> * @license New BSD License * @version $Id: Cache/Apc.php 版本号 2010-04-18 23:02 cmpan $ */class Cache_Apc extends Cache_Abstract {protected $_prefix = 'cache.mjie.net';public function __construct() {if (!function_exists('apc_cache_info')) {throw new CacheException('apc extension didn/'t installed');}}/** * 保存缓存变量 * * @param string $key * @param mixed $value * @return bool */public function store($key, $value) { return apc_store($this->_storageKey($key), $value);}/** * 读取缓存 * * @param string $key * @return mixed */public function fetch($key) { return apc_fetch($this->_storageKey($key));}/** * 清除缓存 * * @return Cache_Apc */public function clear() {apc_clear_cache();return $this;}/** * 删除缓存单元 * * @return Cache_Apc */public function delete($key) { apc_delete($this->_storageKey($key)); return $this;}/** * 缓存单元是否被锁定 * * @param string $key * @return bool */public function isLocked($key) {if ((apc_fetch($this->_storageKey($key) . '.lock')) === false) { return false;}return true;}/** * 锁定缓存单元 * * @param string $key * @return Cache_Apc */public function lock($key) {apc_store($this->_storageKey($key) . '.lock', '', 5);return $this;}/** * 缓存单元解锁 * * @param string $key * @return Cache_Apc */public function unlock($key) {apc_delete($this->_storageKey($key) . '.lock');return $this;}/** * 完整缓存名 * * @param string $key * @return string */private function _storageKey($key) { return $this->_prefix . '_' . $key;}}/** * 文件缓存实现 * * * @category Mjie * @package Cache * @author 流水孟春 * @copyright Copyright (c) 2008- <cmpan(at)qq.com> * @license New BSD License * @version $Id: Cache/File.php 版本号 2010-04-18 16:46 cmpan $ */class Cache_File extends Cache_Abstract {public $useSubdir = false;protected $_cachesDir = 'cache';public function __construct() {if (defined('DATA_DIR')) {$this->_setCacheDir(DATA_DIR . '/cache');}}/** * 获取缓存文件 * * @param string $key * @return string */protected function _getCacheFile($key) {$subdir = $this->useSubdir ? substr($key, 0, 2) . '/' : '';return $this->_cachesDir . '/' . $subdir . $key . '.php';} /** * 读取缓存变量 * 为防止信息泄露，缓存文件格式为php文件，并以"<?php exit;?>"开头 * * @param string $key 缓存下标 * @return mixed */ public function fetch($key) { $cacheFile = self::_getCacheFile($key); if (file_exists($cacheFile) && is_readable($cacheFile)) { // include 方式 //return include $cacheFile; // 系列化方式 return unserialize(@file_get_contents($cacheFile, false, NULL, 13)); } return false; }/** * 缓存变量 * 为防止信息泄露，缓存文件格式为php文件，并以"<?php exit;?>"开头 * * @param string $key 缓存变量下标 * @param string $value 缓存变量的值 * @return bool */ public function store($key, $value) {$cacheFile = self::_getCacheFile($key);$cacheDir = dirname($cacheFile);if(!is_dir($cacheDir)) { if(!@mkdir($cacheDir, 0755, true)) { throw new CacheException("Could not make cache directory"); }}// 用include方式 //return @file_put_contents($cacheFile, '<?php return ' . var_export($value, true). ';'); return @file_put_contents($cacheFile, '<?php exit;?>' . serialize($value));}/** * 删除缓存变量 * * @param string $key 缓存下标 * @return Cache_File */ public function delete($key) { if(empty($key)) { throw new CacheException("Missing argument 1 for Cache_File::delete()");}$cacheFile = self::_getCacheFile($key);if(!@unlink($cacheFile)) { throw new CacheException("Cache file could not be deleted");}return $this;}/** * 缓存单元是否已经锁定 * * @param string $key * @return bool */public function isLocked($key) {$cacheFile = self::_getCacheFile($key);clearstatcache();return file_exists($cacheFile . '.lock');}/** * 锁定 * * @param string $key * @return Cache_File */public function lock($key) {$cacheFile = self::_getCacheFile($key);$cacheDir = dirname($cacheFile);if(!is_dir($cacheDir)) { if(!@mkdir($cacheDir, 0755, true)) { if(!is_dir($cacheDir)) { throw new CacheException("Could not make cache directory"); } }}// 设定缓存锁文件的访问和修改时间@touch($cacheFile . '.lock');return $this;} /** * 解锁 * * @param string $key * @return Cache_File */public function unlock($key) {$cacheFile = self::_getCacheFile($key); @unlink($cacheFile . '.lock');return $this;}/** * 设置文件缓存目录 * @param string $dir * @return Cache_File */protected function _setCacheDir($dir) {$this->_cachesDir = rtrim(str_replace('//', '/', trim($dir)), '/');clearstatcache();if(!is_dir($this->_cachesDir)) {mkdir($this->_cachesDir, 0755, true);}//return $this;}/** * 清空所有缓存 * * @return Cache_File */public function clear() {// 遍历目录清除缓存$cacheDir = $this->_cachesDir;$d = dir($cacheDir);while(false !== ($entry = $d->read())) {if('.' == $entry[0]) {continue;}$cacheEntry = $cacheDir . '/' . $entry;if(is_file($cacheEntry)) {@unlink($cacheEntry);} elseif(is_dir($cacheEntry)) {// 缓存文件夹有两级$d2 = dir($cacheEntry);while(false !== ($entry = $d2->read())) {if('.' == $entry[0]) {continue;}$cacheEntry .= '/' . $entry;if(is_file($cacheEntry)) {@unlink($cacheEntry);}}$d2->close();}}$d->close();return $this;}}/** * 缓存单元的数据结构 * array( * 'time' => time(), // 缓存写入时的时间戳 * 'expire' => $expire, // 缓存过期时间 * 'valid' => true, // 缓存是否有效 * 'data' => $value // 缓存的值 * ); */final class Cache {/** * 缓存过期时间长度(s) * * @var int */private $_expire = 3600;/** * 缓存处理类 * * @var Cache_Abstract */private $_storage = null;/** * @return Cache */static public function createCache($cacheClass = 'Cache_File') {return new self($cacheClass);}private function __construct($cacheClass) {$this->_storage = new $cacheClass();}/** * 设置缓存 * * @param string $key * @param mixed $value * @param int $expire */public function set($key, $value, $expire = false) {if (!$expire) {$expire = $this->_expire;}$this->_storage->checkLock($key);$data = array('time' => time(), 'expire' => $expire, 'valid' => true, 'data' => $value);$this->_storage->lock($key);try {$this->_storage->store($key, $data);$this->_storage->unlock($key);} catch (CacheException $e) {$this->_storage->unlock($key);throw $e;}}/** * 读取缓存 * * @param string $key * @return mixed */public function get($key) {$data = $this->fetch($key);if ($data && $data['valid'] && !$data['isExpired']) {return $data['data'];}return false;}/** * 读缓存，包括过期的和无效的，取得完整的存贮结构 * * @param string $key */public function fetch($key){$this->_storage->checkLock($key);$data = $this->_storage->fetch($key);if ($data) {$data['isExpired'] = (time() - $data['time']) > $data['expire'] ? true : false;return $data;}return false;}/** * 删除缓存 * * @param string $key */public function delete($key) {$this->_storage->checkLock($key) ->lock($key) ->delete($key) ->unlock($key);}public function clear() {$this->_storage->clear();}/** * 把缓存设为无效 * * @param string $key */public function setInvalidate($key) {$this->_storage->checkLock($key) ->lock($key);try {$data = $this->_storage->fetch($key);if ($data) {$data['valid'] = false;$this->_storage->store($key, $data);}$this->_storage->unlock($key);} catch (CacheException $e) {$this->_storage->unlock($key);throw $e;}}/** * 设置缓存过期时间（s） * * @param int $expire */public function setExpire($expire) {$this->_expire = (int)$expire;return $this;}}// 加个例子$cache = Cache::createCache(); // 使用apc来缓存：Cache::createCache('Cache_Apc');// 写缓存$test = array('呵呵', '轰轰');$cache->set('test', $test);// 读缓存$data = $cache->get('test');print_r($data); // 和$test的值一样// 删除缓存$cache->delete('test');// 删除所有缓存$cache->clear();