public function setConfig($config)
    {
        if (is_array($config)) {
            $this->config = new Config($config);
        } else {
            // see if it's a file path
            if (is_file($config)) {
                $cfg = parse_ini_file($config, true);
                $this->config = new Config($cfg);
            } else {
                throw new \InvalidArgumentException(
                    'Could not load configuration file '.$config
                );
            }
        }
    }