owncloud / core

		$isValid = true;

		// Validate

		if (!ctype_digit($minValue) && $minValue !== 'auto') {

			$isValid = false;

			\OC::$server->getLogger()->warning(

					$minValue . ' is not a valid value for minimal versions retention obligation. Check versions_retention_obligation in your config.php. Falling back to auto.',

					['app'=>'files_versions']

			);

		}

		if (!ctype_digit($maxValue) && $maxValue !== 'auto') {

			$isValid = false;

			);

		}

		if (!ctype_digit($maxValue) && $maxValue !== 'auto') {

			$isValid = false;

			\OC::$server->getLogger()->warning(

					$maxValue . ' is not a valid value for maximal versions retention obligation. Check versions_retention_obligation in your config.php. Falling back to auto.',

					['app'=>'files_versions']

			);

		}

		if (!$isValid){

			$minValue = 'auto';

		} catch (Exception $ex) {

			\OC::$server->getLogger()->logException($ex);

			$blacklist = \OC::$server->getAppManager()->getAlwaysEnabledApps();

			if (!in_array($app, $blacklist)) {

				\OC::$server->getLogger()->warning('Could not load app "' . $app . '", it will be disabled', array('app' => 'core'));

				self::disable($app);

			}

			throw $ex;

		}

	}