hashedChunk := hex.EncodeToString(cr.chunkSHA256Writer.Sum(nil))

	// Calculate string to sign.
	alg := signV4ChunkedAlgorithm + "\n"
	stringToSign := alg +
		cr.seedDate.Format(iso8601Format) + "\n" +
		getScope(cr.seedDate, cr.region) + "\n" +
		cr.seedSignature + "\n" +
		emptySHA256 + "\n" +
		hashedChunk

	// Get hmac signing key.
	signingKey := getSigningKey(cr.cred.SecretKey, cr.seedDate, cr.region, serviceS3)

		rawQuery,
		getCanonicalHeaders(extractedSignedHeaders),
		getSignedHeaders(extractedSignedHeaders),
		payload,
	}, "\n")
	return canonicalRequest
}

// getScope generate a string of a specific date, an AWS region, and a service.
func getScope(t time.Time, region string) string {
	scope := strings.Join([]string{
		t.Format(yyyymmdd),
		region,
		string(serviceS3),
		"aws4_request",
	}, SlashSeparator)

type credentialHeader struct {
	accessKey string
	scope     struct {
		date    time.Time
		region  string
		service string
		request string
	}
}

// Return scope string.
func (c credentialHeader) getScope() string {
	return strings.Join([]string{
		c.scope.date.Format(yyyymmdd),
		c.scope.region,
		c.scope.service,
		c.scope.request,
	}, SlashSeparator)
}

	if accessKeyID == "" || secretAccessKey == "" {
		return errors.New("Presign cannot be generated without access and secret keys")
	}

	region := globalSite.Region
	date := UTCNow()
	scope := getScope(date, region)
	credential := fmt.Sprintf("%s/%s", accessKeyID, scope)

	// Set URL query.
	query := req.URL.Query()
	query.Set("X-Amz-Algorithm", signV4Algorithm)

	close(ch)
	for result := range ch {
		if result.err != nil {
			return fmt.Errorf("failed updating Scope %s: %v", result.scopeName, result.err)
		}
	}
	return nil
}

func (c *ControlzClient) GetScope(scope string) (*ScopeInfo, error) {
	var s ScopeInfo
	resp, err := http.Get(c.baseURL.String() + "/" + scope)
	if err != nil {
		return &s, err
	}
	defer resp.Body.Close()