public function sendNotification(NotificationInterface $notification)
    {
        $uri = $notification->buildUri($this->endpoint, $this->hubPath).self::API_VERSION;

        $token = $this->generateSasToken($uri);
        $headers = array_merge(['Authorization: '.$token], $notification->getHeaders());

        $this->request(self::METHOD_POST, $uri, $headers, $notification->getPayload());
    }