private static string GetSecretKey(AwsSettings awsSettings)
{
var key = awsSettings.SecretKey;
if (!string.IsNullOrWhiteSpace(key)) return key;
#if NET45
key = System.Configuration.ConfigurationManager.AppSettings["AWSSecretKey"];
if (!string.IsNullOrWhiteSpace(key)) return key;
#endif
return Environment.GetEnvironmentVariable("AWS_SECRET_ACCESS_KEY");
}