rss-bridge/caches/FileCache.php
Dag 6254b8593e
refactor(cache): extract and encapsulate cache expiration logic (#3547)
* refactor(cache): extract and encapsulate cache expiration logic

* fix: logic bug in getSimpleHTMLDOMCached

* fix: silly me, index should of course be on the key column

* silly me again, PRIMARY keys get index by default lol

* comment out the delete portion in loadData

* remove a few log statements

* tweak twitter cache timeout
2023-07-19 05:05:49 +02:00

147 lines
4.1 KiB
PHP

<?php
/**
* @link https://www.php.net/manual/en/function.clearstatcache.php
*/
class FileCache implements CacheInterface
{
private array $config;
protected string $scope;
protected string $key;
public function __construct(array $config = [])
{
$default = [
'path' => null,
'enable_purge' => true,
];
$this->config = array_merge($default, $config);
if (!$this->config['path']) {
throw new \Exception('The FileCache needs a path value');
}
// Normalize with a single trailing slash
$this->config['path'] = rtrim($this->config['path'], '/') . '/';
}
public function getConfig()
{
return $this->config;
}
public function loadData(int $timeout = 86400)
{
clearstatcache();
if (!file_exists($this->getCacheFile())) {
return null;
}
$modificationTime = filemtime($this->getCacheFile());
if (time() - $timeout < $modificationTime) {
$data = unserialize(file_get_contents($this->getCacheFile()));
if ($data === false) {
Logger::warning(sprintf('Failed to unserialize: %s', $this->getCacheFile()));
// Intentionally not throwing an exception
return null;
}
return $data;
}
// It's a good idea to delete the expired item here, but commented out atm
// unlink($this->getCacheFile());
return null;
}
public function saveData($data): void
{
$bytes = file_put_contents($this->getCacheFile(), serialize($data), LOCK_EX);
if ($bytes === false) {
throw new \Exception(sprintf('Failed to write to: %s', $this->getCacheFile()));
}
}
public function getTime(): ?int
{
clearstatcache();
$cacheFile = $this->getCacheFile();
if (file_exists($cacheFile)) {
$time = filemtime($cacheFile);
if ($time !== false) {
return $time;
}
return null;
}
return null;
}
public function purgeCache(int $timeout = 86400): void
{
if (! $this->config['enable_purge']) {
return;
}
$cachePath = $this->getScope();
if (!file_exists($cachePath)) {
return;
}
$cacheIterator = new \RecursiveIteratorIterator(
new \RecursiveDirectoryIterator($cachePath),
\RecursiveIteratorIterator::CHILD_FIRST
);
foreach ($cacheIterator as $cacheFile) {
$basename = $cacheFile->getBasename();
$excluded = [
'.' => true,
'..' => true,
'.gitkeep' => true,
];
if (isset($excluded[$basename])) {
continue;
} elseif ($cacheFile->isFile()) {
$filepath = $cacheFile->getPathname();
if (filemtime($filepath) < time() - $timeout) {
// todo: sometimes this file doesn't exists
unlink($filepath);
}
}
}
}
public function setScope(string $scope): void
{
$this->scope = $this->config['path'] . trim($scope, " \t\n\r\0\x0B\\\/") . '/';
}
public function setKey(array $key): void
{
$this->key = json_encode($key);
}
private function getScope()
{
if (is_null($this->scope)) {
throw new \Exception('Call "setScope" first!');
}
if (!is_dir($this->scope)) {
if (mkdir($this->scope, 0755, true) !== true) {
throw new \Exception('mkdir: Unable to create file cache folder');
}
}
return $this->scope;
}
private function getCacheFile()
{
return $this->getScope() . $this->getCacheName();
}
private function getCacheName()
{
if (is_null($this->key)) {
throw new \Exception('Call "setKey" first!');
}
return hash('md5', $this->key) . '.cache';
}
}