friendica/src/Factory/LockFactory.php
2020-02-09 15:45:36 +01:00

145 lines
3.9 KiB
PHP

<?php
/**
* @copyright Copyright (C) 2020, Friendica
*
* @license GNU AGPL version 3 or any later version
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*
*/
namespace Friendica\Factory;
use Friendica\Core\Cache\IMemoryCache;
use Friendica\Core\Cache\Type;
use Friendica\Core\Config\IConfig;
use Friendica\Core\Lock;
use Friendica\Database\Database;
use Psr\Log\LoggerInterface;
/**
* Class LockFactory
*
* @package Friendica\Core\Cache
*
* A basic class to generate a LockDriver
*/
class LockFactory
{
/**
* @var string The default driver for caching
*/
const DEFAULT_DRIVER = 'default';
/**
* @var IConfig The configuration to read parameters out of the config
*/
private $config;
/**
* @var Database The database connection in case that the cache is used the dba connection
*/
private $dba;
/**
* @var CacheFactory The memory cache driver in case we use it
*/
private $cacheFactory;
/**
* @var LoggerInterface The Friendica Logger
*/
private $logger;
public function __construct(CacheFactory $cacheFactory, IConfig $config, Database $dba, LoggerInterface $logger)
{
$this->cacheFactory = $cacheFactory;
$this->config = $config;
$this->dba = $dba;
$this->logger = $logger;
}
public function create()
{
$lock_type = $this->config->get('system', 'lock_driver', self::DEFAULT_DRIVER);
try {
switch ($lock_type) {
case Type::MEMCACHE:
case Type::MEMCACHED:
case Type::REDIS:
case Type::APCU:
$cache = $this->cacheFactory->create($lock_type);
if ($cache instanceof IMemoryCache) {
return new Lock\CacheLock($cache);
} else {
throw new \Exception(sprintf('Incompatible cache driver \'%s\' for lock used', $lock_type));
}
break;
case 'database':
return new Lock\DatabaseLock($this->dba);
break;
case 'semaphore':
return new Lock\SemaphoreLock();
break;
default:
return self::useAutoDriver();
}
} catch (\Exception $exception) {
$this->logger->alert('Driver \'' . $lock_type . '\' failed - Fallback to \'useAutoDriver()\'', ['exception' => $exception]);
return self::useAutoDriver();
}
}
/**
* This method tries to find the best - local - locking method for Friendica
*
* The following sequence will be tried:
* 1. Semaphore Locking
* 2. Cache Locking
* 3. Database Locking
*
* @return Lock\ILock
*/
private function useAutoDriver()
{
// 1. Try to use Semaphores for - local - locking
if (function_exists('sem_get')) {
try {
return new Lock\SemaphoreLock();
} catch (\Exception $exception) {
$this->logger->debug('Using Semaphore driver for locking failed.', ['exception' => $exception]);
}
}
// 2. Try to use Cache Locking (don't use the DB-Cache Locking because it works different!)
$cache_type = $this->config->get('system', 'cache_driver', 'database');
if ($cache_type != Type::DATABASE) {
try {
$cache = $this->cacheFactory->create($cache_type);
if ($cache instanceof IMemoryCache) {
return new Lock\CacheLock($cache);
}
} catch (\Exception $exception) {
$this->logger->debug('Using Cache driver for locking failed.', ['exception' => $exception]);
}
}
// 3. Use Database Locking as a Fallback
return new Lock\DatabaseLock($this->dba);
}
}