public static function validateActionsConfig(array $json) : void
    {
        foreach ($json as $action) {
            if (!self::keysExist(['action'], $action)) {
                throw new \RuntimeException('Config error: \'action\' missing');
            }
            if (empty($action['action'])) {
                throw new \RuntimeException('Config error: \'action\' can\'t be empty');
            }
            if (!empty($action['conditions'])) {
                self::validateConditionsConfig($action['conditions']);
            }
        }
    }