if len(meta.TaggingConfigXML) > 0 {
				tagCfgStr := base64.StdEncoding.EncodeToString(meta.TaggingConfigXML)
				bms.Tags = &tagCfgStr
				bms.TagConfigUpdatedAt = meta.TaggingConfigUpdatedAt
			}

			if len(meta.VersioningConfigXML) > 0 {
				versioningCfgStr := base64.StdEncoding.EncodeToString(meta.VersioningConfigXML)
				bms.Versioning = &versioningCfgStr

	region := sumHMAC(date, []byte(globalMinioDefaultRegion))
	service := sumHMAC(region, []byte(string(serviceS3)))
	signingKey := sumHMAC(service, []byte("aws4_request"))

	signature := hex.EncodeToString(sumHMAC(signingKey, []byte(stringToSign)))

	// final Authorization header
	parts := []string{
		"AWS4-HMAC-SHA256" + " Credential=" + accessKey + SlashSeparator + scope,
		"SignedHeaders=" + signedHeaders,

        switch (form.crudMode) {
        case CrudMode.CREATE:
            return OptionalEntity.of(new User()).map(entity -> {
                entity.setId(Base64.getUrlEncoder().encodeToString(form.name.getBytes(Constants.CHARSET_UTF_8)));
                return entity;
            });
        case CrudMode.EDIT:
            if (form instanceof EditForm) {

		// We use a hash of the plugin URL so that the ARN remains
		// constant across restarts.
		h := sha1.New()
		h.Write([]byte(pluginURL))
		bs := h.Sum(nil)
		resourceID += base64.RawURLEncoding.EncodeToString(bs)
	} else {
		// Check that the roleID is restricted to URL safe characters
		// (base64 URL encoding chars).
		if !validRoleIDRegex.MatchString(roleID) {

        }).orElse(null);
    }

    public static String base64(final String value) {
        if (value == null) {
            return StringUtil.EMPTY;
        }
        return Base64.getUrlEncoder().encodeToString(value.getBytes(Constants.CHARSET_UTF_8));
    }

    public static boolean fileExists(final String path) {
        final File file = new File(LaServletContextUtil.getServletContext().getRealPath(path));

		Signature string
		Type      uint8
		Flags     uint8
		EcM, EcN  uint8 // Note that these will be 0/0 for non-v2 objects and older xl.meta
	}{
		VersionID: hex.EncodeToString(z.VersionID[:]),
		ModTime:   time.Unix(0, z.ModTime),
		Signature: hex.EncodeToString(z.Signature[:]),
		Type:      z.Type,
		Flags:     z.Flags,
		EcM:       z.EcM,
		EcN:       z.EcN,
	}
	return json.Marshal(tmp)
}

		if err != nil {
			logger.CriticalIf(GlobalContext, err)
		}
		sum256 := sha256.Sum256(payload)
		r.Body = io.NopCloser(bytes.NewReader(payload))
		return hex.EncodeToString(sum256[:])
	}

	var (
		defaultSha256Cksum string
		v                  []string
		ok                 bool
	)

	// For a presigned request we look at the query param for sha256.

		if format == nil {
			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 := ""

		if err != nil {
			writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
			return
		}

		// Set the correct hex md5sum for the fan-out stream.
		fanOutOpts.MD5Hex = hex.EncodeToString(md5w.Sum(nil))

		concurrentSize := 100
		if runtime.GOMAXPROCS(0) < concurrentSize {
			concurrentSize = runtime.GOMAXPROCS(0)
		}

	}
	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 {