regA(builder);
        return builder;
    }

    protected SumAggregationBuilder regSumA(String name, String field) {
        SumAggregationBuilder builder = AggregationBuilders.sum(name).field(field);
        regA(builder);
        return builder;
    }

    protected ExtendedStatsAggregationBuilder regExtendedStatsA(String name, String field) {

	return cred, owner, ErrNone
}

// sumHMAC calculate hmac between two input byte array.
func sumHMAC(key []byte, data []byte) []byte {
	hash := hmac.New(sha256.New, key)
	hash.Write(data)
	return hash.Sum(nil)
}

// extractSignedHeaders extract signed headers from Authorization header
func extractSignedHeaders(signedHeaders []string, r *http.Request) (http.Header, APIErrorCode) {
	reqHeaders := r.Header

     * estimate without locking. Note that the number, if not exactly accurate, is *always*
     * underestimating, never overestimating.
     */
    long bitCount() {
      return bitCount.sum();
    }

    LockFreeBitArray copy() {
      return new LockFreeBitArray(toPlainArray(data));
    }

    /**
     * Combines the two BitArrays using bitwise OR.
     *

	if err != nil {
		logger.Error("Calculating checksum failed: %s", err)
		return "00000000000000000000000000000000"
	}

	defer b.Close()
	io.Copy(mw, b)
	return hex.EncodeToString(mw.Sum(nil))
}

func verifyServerSystemConfig(ctx context.Context, endpointServerPools EndpointServerPools, gm *grid.Manager) error {
	srcCfg := getServerSystemCfg()
	clnts := newBootstrapRESTClients(endpointServerPools, gm)

)

// getChunkSignature - get chunk signature.
// Does not update anything in cr.
func (cr *s3ChunkedReader) getChunkSignature() string {
	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" +

	}
	return ErrNone
}

func calculateSignatureV2(stringToSign string, secret string) string {
	hm := hmac.New(sha1.New, []byte(secret))
	hm.Write([]byte(stringToSign))
	return base64.StdEncoding.EncodeToString(hm.Sum(nil))
}

// Return signature-v2 for the presigned request.
func preSignatureV2(cred auth.Credentials, method string, encodedResource string, encodedQuery string, headers http.Header, expires string) string {

   The `read_vs_write_current_requests` metric histogram is adjusted, in the case of using API Priority and Fairness instead of max-in-flight, to divide by the relevant limit: sum of queue capacities for waiting requests, sum of seat limits for executing requests. ([#110164](https://github.com/kubernetes/kubernetes/pull/110164), [@MikeSpreitzer](https://github.com/MikeSpreitzer))

			continue
		}
		h := sha256.New()
		for _, set := range format.Erasure.Sets {
			for _, diskID := range set {
				h.Write([]byte(diskID))
			}
		}
		formatHashes[i] = hex.EncodeToString(h.Sum(nil))
	}

	formatCountMap := make(map[string]int)
	for _, hash := range formatHashes {
		if hash == "" {
			continue
		}
		formatCountMap[hash]++
	}

	maxHash := ""
	maxCount := 0

	}
	uploadID := res.UploadID

	// Upload part1.
	fiveMBBytes := bytes.Repeat([]byte("a"), 5*humanize.MiByte)
	md5Writer := md5.New()
	md5Writer.Write(fiveMBBytes)
	etag1 := hex.EncodeToString(md5Writer.Sum(nil))
	sha256sum := ""
	_, err = obj.PutObjectPart(context.Background(), bucket, object, uploadID, 1, mustGetPutObjReader(t, bytes.NewReader(fiveMBBytes), int64(len(fiveMBBytes)), etag1, sha256sum), opts)
	if err != nil {

			Value:       float64(offlineDrives.Sum()),
		})

		metrics = append(metrics, MetricV2{
			Description: getNodeDrivesOnlineTotalMD(),
			Value:       float64(onlineDrives.Sum()),
		})

		metrics = append(metrics, MetricV2{
			Description: getNodeDrivesTotalMD(),
			Value:       float64(totalDrives.Sum()),
		})

		metrics = append(metrics, MetricV2{