//   - validates the policy action if anonymous tests bucket policies if any,
//     for authenticated requests validates IAM policies.
//
// returns APIErrorCode if any to be replied to the client.
func checkRequestAuthType(ctx context.Context, r *http.Request, action policy.Action, bucketName, objectName string) (s3Err APIErrorCode) {
	logger.GetReqInfo(ctx).BucketName = bucketName
	logger.GetReqInfo(ctx).ObjectName = objectName