/**
* Cleans the current file cache by deleting unused files.
* @param \System\Db\Database The database to LUT query
*/
public static final function cleanPageCache(\System\Db\Database $db)
{
$results = \System\Cache\LUTCache\LUTCache::getCache($db);
$baseFiles = new \System\Collection\Vector();
foreach ($results as $result) {
$baseFiles[] = basename($result->value);
}
$folder = new \System\IO\Directory(\System\Cache\PageCache\StaticBlock::CACHE_CACHEFOLDER);
$extensions = new \System\Collection\Vector('xml');
$files = $folder->getFiles($extensions);
foreach ($files as $file) {
/** @var \System\IO\File */
$file = $file;
if (mb_strpos($file->getFilename(), 'PageCache') !== false) {
if (!$baseFiles->contains($file->getFilename())) {
$file->delete();
}
}
}
}
/**
* Calls the corresponding function in the block and checks for LUT availability.
* @return \SimpleXMLElement The XML data tree
*/
public final function callStaticBlock()
{
$db = $this->getDatabase();
$xml = '';
$filename = null;
$returnVal = \System\Cache\LUTCache\LUTCache::retrieve($db, $this->getLUTKey(), $filename);
switch ($returnVal) {
case \System\Cache\LUTCache\Status::CACHE_GENERATING:
$totalWaitTime = 0;
while (($returnVal = \System\Cache\LUTCache\LUTCache::retrieve($db, $this->getLUTKey(), $filename)) == \System\Cache\LUTCache\Status::CACHE_GENERATING) {
//we wait before polling the system again
usleep(self::CACHE_GENERATE_POLL_TIME);
$totalWaitTime += self::CACHE_GENERATE_POLL_TIME;
if ($totalWaitTime >= self::CACHE_GENERATE_WAIT_THRESHOLD) {
throw new \System\Error\Exception\LUTCacheTimeoutException('The generation timeout is exceeded for block: ' . $this->getLUTKey());
}
}
if ($returnVal != \System\Cache\LUTCache\Status::CACHE_HIT) {
throw new \Exception('Invalid LUT returnvalue given after generation: ' . $returnVal);
}
//we do a fallthrough after we are done generating
//we do a fallthrough after we are done generating
case \System\Cache\LUTCache\Status::CACHE_HIT:
//get stuff
$fullFile = self::getWritablePath($filename) . $filename;
if (file_exists($fullFile)) {
//suppress warnings here in case of malformed xml
if ($xml = @simplexml_load_file($fullFile)) {
break;
} else {
$errorLogger = \System\Log\ErrorLogger::getInstance();
$errorLogger->out('[StaticBlock] Could not read ' . $fullFile . ' as XML. Regenerating.', \System\Log\LoggerLevel::LEVEL_WARNING);
}
}
//if the file does not exist, we do a fallthrough to the generation
//if the file does not exist, we do a fallthrough to the generation
case \System\Cache\LUTCache\Status::CACHE_MISS:
case \System\Cache\LUTCache\Status::CACHE_INVALIDATED:
//set to currently generating
\System\Cache\LUTCache\LUTCache::setToGenerate($db, $this->getLUTKey());
//get the XML
$xml = $this->callBlock($this);
//store the xml to a file and add the file to the LUT
$cacheFile = self::FILENAME_PREFIX . uniqid() . self::FILENAME_EXTENSION;
$fullFile = self::getWritablePath($cacheFile) . $cacheFile;
$xml->asXML($fullFile);
\System\Cache\LUTCache\LUTCache::store($db, $this->getLUTKey(), $cacheFile);
break;
default:
throw new \Exception('Invalid LUT returnvalue given: ' . $returnVal);
}
return $xml;
}
