public function validatesftpAction()
    {
        $request = $this->getRequest();

        $configMap = Mage::getModel('radial_core/config');
        $host = $this->_validatorHelper->getParamOrFallbackValue(
            $request,
            self::SFTP_HOSTNAME_PARAM,
            self::SFTP_HOSTNAME_USE_DEFAULT_PARAM,
            $configMap->getPathForKey('sftp_location')
        );
        $username = $this->_validatorHelper->getParamOrFallbackValue(
            $request,
            self::SFTP_USERNAME_PARAM,
            self::SFTP_USERNAME_USE_DEFAULT_PARAM,
            $configMap->getPathForKey('sftp_username')
        );
        $port = $this->_validatorHelper->getParamOrFallbackValue(
            $request,
            self::SFTP_PORT_PARAM,
            self::SFTP_PORT_USE_DEFAULT_PARAM,
            $configMap->getPathForKey('sftp_port')
        );
        $key = $this->_validatorHelper->getSftpPrivateKey(
            $request,
            self::SFTP_PRIV_KEY_PARAM,
            self::SFTP_PRIV_KEY_USE_DEFAULT_PARAM,
            Mage::getSingleton('radial_core/config')->getPathForKey('sftp_private_key')
        );

        $this->getResponse()->setHeader('Content-Type', 'text/json')
            ->setBody(json_encode(Mage::helper('radial_core/validator')->testSftpConnection($host, $username, $key, $port)));
        return $this;
    }