public function post($url, array $options = [])
    {
        $request = new Request(
            'GET',
            $url,
            ['User-Agent' => self::PHP_GA_MEASUREMENT_PROTOCOL_USER_AGENT]
        );

        $opts = $this->parseOptions($options);
        $response = $this->getClient()->sendAsync($request, [
            'synchronous' => !$opts['async'],
            'timeout' => $opts['timeout'],
            'connect_timeout' => $opts['timeout'],
        ]);

        if ($opts['async']) {
            self::$promises[] = $response;
        } else {
            $response = $response->wait();
        }

        return $this->getAnalyticsResponse($request, $response);
    }