private function getHttpClientConfig()
    {
        $config = [
            'base_uri' => 'http://ip-api.com/',
            'headers' => [
                'User-Agent' => 'Laravel-GeoIP',
            ],
            'query' => [
                'fields' => 16895,
            ],
        ];

        // Using the Pro service
        if ($this->getOption('key')) {
            $config['base_uri']     = $this->isSecure() ? 'https://pro.ip-api.com/' : 'http://pro.ip-api.com/';
            $config['query']['key'] = $this->getOption('key');
        }

        return $config;
    }