private void ValidateSettings()
{
if (string.IsNullOrWhiteSpace(ApiKey)) throw new ArgumentException("api key is required");
if (string.IsNullOrWhiteSpace(Secret)) throw new ArgumentException("secret key is required");
if (string.IsNullOrWhiteSpace(Server)) throw new ArgumentException("server is required");
if (string.IsNullOrWhiteSpace(TokenSentinel)) throw new ArgumentException("token sentinel is required");
if (string.IsNullOrWhiteSpace(SdkVersion)) throw new ArgumentException("sdk version is required");
}