protected function getConfig()
    {
        if ($this->config === null) {
            if (file_exists($this->filename)) {
                $this->filename = realpath($this->filename);
                $this->config = new Config(include $this->filename, true);
            } else {
                $this->filename = getcwd() . $this->filename;
                $this->config = new Config([], true);
            }
        }
        return $this->config;
    }