return strings.Join([]string{
		accessKey,
		date,
		region,
		service,
		requestVersion,
	}, SlashSeparator)
}

// generate CredentialHeader from its fields.
func generateCredentials(t *testing.T, accessKey string, date string, region, service, requestVersion string) credentialHeader {
	cred := credentialHeader{
		accessKey: accessKey,
	}
	parsedDate, err := time.Parse(yyyymmdd, date)

	default:
		expAt, err = 0, ErrInvalidDuration
	}
	if expAt < 0 {
		return 0, ErrInvalidDuration
	}
	return expAt, err
}

// GenerateCredentials - creates randomly generated credentials of maximum
// allowed length.
func GenerateCredentials() (accessKey, secretKey string, err error) {
	accessKey, err = GenerateAccessKey(accessKeyMaxLen, rand.Reader)
	if err != nil {
		return "", "", err
	}