protected function createWebClient()
    {
        $userId = array_get($this->config, 'user_id', false);
        $licenseKey = array_get($this->config, 'license_key', false);

        // check and make sure they are set
        if (! $userId || ! $licenseKey) {
            throw new InvalidCredentialsException();
        }

        return new Client($userId, $licenseKey);
    }