public function getAppURL()
    {
        if (empty($this->appURL)) {
            $hostname = $this->getHostname();
            if (empty($hostname)) {
                $this->appURL = config('app.url');
            } else {
                $protocol = $this->getProtocol();
                $this->appURL = ($protocol ?: 'http') . '://' . $hostname . '/' . $this->getBaseDir();
            }
        }

        return $this->appURL;
    }