CacheEngine::connect

protected function connect($config)
{
	$connectionPool = Application::getInstance()->getConnectionPool();
	$connectionPool->setConnectionParameters($this->getConnectionName(), $config);

	/** @var RedisConnection|MemcacheConnection|MemcachedConnection $engineConnection */
	$engineConnection = $connectionPool->getConnection($this->getConnectionName());
	self::$engine = $engineConnection->getResource();
	self::$isConnected = $engineConnection->isConnected();
}