<?php
/**
* CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
* Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
*
* Licensed under The MIT License
* For full copyright and license information, please see the LICENSE.txt
* Redistributions of files must retain the above copyright notice.
*
* @copyright Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
* @link https://cakephp.org CakePHP(tm) Project
* @since 1.2.0
* @license https://opensource.org/licenses/mit-license.php MIT License
*/
namespace Cake\Cache\Engine;
use Cake\Cache\CacheEngine;
use Cake\Utility\Inflector;
use CallbackFilterIterator;
use Exception;
use LogicException;
use RecursiveDirectoryIterator;
use RecursiveIteratorIterator;
use SplFileInfo;
use SplFileObject;
/**
* File Storage engine for cache. Filestorage is the slowest cache storage
* to read and write. However, it is good for servers that don't have other storage
* engine available, or have content which is not performance sensitive.
*
* You can configure a FileEngine cache, using Cache::config()
*/
class FileEngine extends CacheEngine
{
/**
* Instance of SplFileObject class
*
* @var \SplFileObject|null
*/
protected $_File;
/**
* The default config used unless overridden by runtime configuration
*
* - `duration` Specify how long items in this cache configuration last.
* - `groups` List of groups or 'tags' associated to every key stored in this config.
* handy for deleting a complete group from cache.
* - `isWindows` Automatically populated with whether the host is windows or not
* - `lock` Used by FileCache. Should files be locked before writing to them?
* - `mask` The mask used for created files
* - `path` Path to where cachefiles should be saved. Defaults to system's temp dir.
* - `prefix` Prepended to all entries. Good for when you need to share a keyspace
* with either another cache config or another application.
* - `probability` Probability of hitting a cache gc cleanup. Setting to 0 will disable
* cache::gc from ever being called automatically.
* - `serialize` Should cache objects be serialized first.
*
* @var array
*/
protected $_defaultConfig = [
'duration' => 3600,
'groups' => [],
'isWindows' => false,
'lock' => true,
'mask' => 0664,
'path' => null,
'prefix' => 'cake_',
'probability' => 100,
'serialize' => true,
];
/**
* True unless FileEngine::__active(); fails
*
* @var bool
*/
protected $_init = true;
/**
* Initialize File Cache Engine
*
* Called automatically by the cache frontend.
*
* @param array $config array of setting for the engine
* @return bool True if the engine has been successfully initialized, false if not
*/
public function init(array $config = [])
{
parent::init($config);
if ($this->_config['path'] === null) {
$this->_config['path'] = sys_get_temp_dir() . DIRECTORY_SEPARATOR . 'cake_cache' . DIRECTORY_SEPARATOR;
}
if (DIRECTORY_SEPARATOR === '\\') {
$this->_config['isWindows'] = true;
}
if (substr($this->_config['path'], -1) !== DIRECTORY_SEPARATOR) {
$this->_config['path'] .= DIRECTORY_SEPARATOR;
}
if ($this->_groupPrefix) {
$this->_groupPrefix = str_replace('_', DIRECTORY_SEPARATOR, $this->_groupPrefix);
}
return $this->_active();
}
/**
* Garbage collection. Permanently remove all expired and deleted data
*
* @param int|null $expires [optional] An expires timestamp, invalidating all data before.
* @return bool True if garbage collection was successful, false on failure
*/
public function gc($expires = null)
{
return $this->clear(true);
}
/**
* Write data for key into cache
*
* @param string $key Identifier for the data
* @param mixed $data Data to be cached
* @return bool True if the data was successfully cached, false on failure
*/
public function write($key, $data)
{
if ($data === '' || !$this->_init) {
return false;
}
$key = $this->_key($key);
if ($this->_setKey($key, true) === false) {
return false;
}
$lineBreak = "\n";
if ($this->_config['isWindows']) {
$lineBreak = "\r\n";
}
if (!empty($this->_config['serialize'])) {
if ($this->_config['isWindows']) {
$data = str_replace('\\', '\\\\\\\\', serialize($data));
} else {
$data = serialize($data);
}
}
$duration = $this->_config['duration'];
$expires = time() + $duration;
$contents = implode([$expires, $lineBreak, $data, $lineBreak]);
if ($this->_config['lock']) {
$this->_File->flock(LOCK_EX);
}
$this->_File->rewind();
$success = $this->_File->ftruncate(0) &&
$this->_File->fwrite($contents) &&
$this->_File->fflush();
if ($this->_config['lock']) {
$this->_File->flock(LOCK_UN);
}
$this->_File = null;
return $success;
}
/**
* Read a key from the cache
*
* @param string $key Identifier for the data
* @return mixed The cached data, or false if the data doesn't exist, has
* expired, or if there was an error fetching it
*/
public function read($key)
{
$key = $this->_key($key);
if (!$this->_init || $this->_setKey($key) === false) {
return false;
}
if ($this->_config['lock']) {
$this->_File->flock(LOCK_SH);
}
$this->_File->rewind();
$time = time();
$cachetime = (int)$this->_File->current();
if ($cachetime < $time) {
if ($this->_config['lock']) {
$this->_File->flock(LOCK_UN);
}
return false;
}
$data = '';
$this->_File->next();
while ($this->_File->valid()) {
$data .= $this->_File->current();
$this->_File->next();
}
if ($this->_config['lock']) {
$this->_File->flock(LOCK_UN);
}
$data = trim($data);
if ($data !== '' && !empty($this->_config['serialize'])) {
if ($this->_config['isWindows']) {
$data = str_replace('\\\\\\\\', '\\', $data);
}
$data = unserialize((string)$data);
}
return $data;
}
/**
* Delete a key from the cache
*
* @param string $key Identifier for the data
* @return bool True if the value was successfully deleted, false if it didn't
* exist or couldn't be removed
*/
public function delete($key)
{
$key = $this->_key($key);
if ($this->_setKey($key) === false || !$this->_init) {
return false;
}
$path = $this->_File->getRealPath();
$this->_File = null;
//@codingStandardsIgnoreStart
return @unlink($path);
//@codingStandardsIgnoreEnd
}
/**
* Delete all values from the cache
*
* @param bool $check Optional - only delete expired cache items
* @return bool True if the cache was successfully cleared, false otherwise
*/
public function clear($check)
{
if (!$this->_init) {
return false;
}
$this->_File = null;
$threshold = $now = false;
if ($check) {
$now = time();
$threshold = $now - $this->_config['duration'];
}
$this->_clearDirectory($this->_config['path'], $now, $threshold);
$directory = new RecursiveDirectoryIterator(
$this->_config['path'],
\FilesystemIterator::SKIP_DOTS
);
$contents = new RecursiveIteratorIterator(
$directory,
RecursiveIteratorIterator::SELF_FIRST
);
$cleared = [];
foreach ($contents as $path) {
if ($path->isFile()) {
continue;
}
$path = $path->getRealPath() . DIRECTORY_SEPARATOR;
if (!in_array($path, $cleared, true)) {
$this->_clearDirectory($path, $now, $threshold);
$cleared[] = $path;
}
}
return true;
}
/**
* Used to clear a directory of matching files.
*
* @param string $path The path to search.
* @param int $now The current timestamp
* @param int $threshold Any file not modified after this value will be deleted.
* @return void
*/
protected function _clearDirectory($path, $now, $threshold)
{
if (!is_dir($path)) {
return;
}
$prefixLength = strlen($this->_config['prefix']);
$dir = dir($path);
while (($entry = $dir->read()) !== false) {
if (substr($entry, 0, $prefixLength) !== $this->_config['prefix']) {
continue;
}
try {
$file = new SplFileObject($path . $entry, 'r');
} catch (Exception $e) {
continue;
}
if ($threshold) {
$mtime = $file->getMTime();
if ($mtime > $threshold) {
continue;
}
$expires = (int)$file->current();
if ($expires > $now) {
continue;
}
}
if ($file->isFile()) {
$filePath = $file->getRealPath();
$file = null;
//@codingStandardsIgnoreStart
@unlink($filePath);
//@codingStandardsIgnoreEnd
}
}
$dir->close();
}
/**
* Not implemented
*
* @param string $key The key to decrement
* @param int $offset The number to offset
* @return void
* @throws \LogicException
*/
public function decrement($key, $offset = 1)
{
throw new LogicException('Files cannot be atomically decremented.');
}
/**
* Not implemented
*
* @param string $key The key to increment
* @param int $offset The number to offset
* @return void
* @throws \LogicException
*/
public function increment($key, $offset = 1)
{
throw new LogicException('Files cannot be atomically incremented.');
}
/**
* Sets the current cache key this class is managing, and creates a writable SplFileObject
* for the cache file the key is referring to.
*
* @param string $key The key
* @param bool $createKey Whether the key should be created if it doesn't exists, or not
* @return bool true if the cache key could be set, false otherwise
*/
protected function _setKey($key, $createKey = false)
{
$groups = null;
if ($this->_groupPrefix) {
$groups = vsprintf($this->_groupPrefix, $this->groups());
}
$dir = $this->_config['path'] . $groups;
if (!is_dir($dir)) {
mkdir($dir, 0775, true);
}
$path = new SplFileInfo($dir . $key);
if (!$createKey && !$path->isFile()) {
return false;
}
if (
empty($this->_File) ||
$this->_File->getBasename() !== $key ||
$this->_File->valid() === false
) {
$exists = file_exists($path->getPathname());
try {
$this->_File = $path->openFile('c+');
} catch (Exception $e) {
trigger_error($e->getMessage(), E_USER_WARNING);
return false;
}
unset($path);
if (!$exists && !chmod($this->_File->getPathname(), (int)$this->_config['mask'])) {
trigger_error(sprintf(
'Could not apply permission mask "%s" on cache file "%s"',
$this->_File->getPathname(),
$this->_config['mask']
), E_USER_WARNING);
}
}
return true;
}
/**
* Determine if cache directory is writable
*
* @return bool
*/
protected function _active()
{
$dir = new SplFileInfo($this->_config['path']);
$path = $dir->getPathname();
$success = true;
if (!is_dir($path)) {
//@codingStandardsIgnoreStart
$success = @mkdir($path, 0775, true);
//@codingStandardsIgnoreEnd
}
$isWritableDir = ($dir->isDir() && $dir->isWritable());
if (!$success || ($this->_init && !$isWritableDir)) {
$this->_init = false;
trigger_error(sprintf(
'%s is not writable',
$this->_config['path']
), E_USER_WARNING);
}
return $success;
}
/**
* Generates a safe key for use with cache engine storage engines.
*
* @param string $key the key passed over
* @return mixed string $key or false
*/
public function key($key)
{
if (empty($key)) {
return false;
}
$key = Inflector::underscore(str_replace(
[DIRECTORY_SEPARATOR, '/', '.', '<', '>', '?', ':', '|', '*', '"'],
'_',
(string)$key
));
return $key;
}
/**
* Recursively deletes all files under any directory named as $group
*
* @param string $group The group to clear.
* @return bool success
*/
public function clearGroup($group)
{
$this->_File = null;
$prefix = (string)$this->_config['prefix'];
$directoryIterator = new RecursiveDirectoryIterator($this->_config['path']);
$contents = new RecursiveIteratorIterator(
$directoryIterator,
RecursiveIteratorIterator::CHILD_FIRST
);
$filtered = new CallbackFilterIterator(
$contents,
function (SplFileInfo $current) use ($group, $prefix) {
if (!$current->isFile()) {
return false;
}
$hasPrefix = $prefix === ''
|| strpos($current->getBasename(), $prefix) === 0;
if ($hasPrefix === false) {
return false;
}
$pos = strpos(
$current->getPathname(),
DIRECTORY_SEPARATOR . $group . DIRECTORY_SEPARATOR
);
return $pos !== false;
}
);
foreach ($filtered as $object) {
$path = $object->getPathname();
$object = null;
// @codingStandardsIgnoreLine
@unlink($path);
}
return true;
}
}