TaggingTimestamp = "tagging-timestamp"
	// ObjectLockRetentionTimestamp - the last time a object lock metadata modification happened on this cluster for this object version
	ObjectLockRetentionTimestamp = "objectlock-retention-timestamp"
	// ObjectLockLegalHoldTimestamp - the last time a legal hold metadata modification happened on this cluster for this object version
	ObjectLockLegalHoldTimestamp = "objectlock-legalhold-timestamp"

	MaximumFileSize int64

	// FileNameFunc specifies the name a new file will take.
	// FileNameFunc must ensure collisions in filenames do not occur.
	// Do not rely on timestamps to be unique, high throughput writes
	// may fall on the same timestamp.
	// Eg.
	// 	2020-03-28_15-00-945-<random-hash>.log
	// When FileNameFunc is not specified, DefaultFilenameFunc will be used.
	FileNameFunc func() string

			srcTimestamp := dstOpts.ReplicationSourceTaggingTimestamp
			if !srcTimestamp.IsZero() {
				ondiskTimestamp, err := time.Parse(time.RFC3339Nano, lastTaggingTimestamp)
				// update tagging metadata only if replica  timestamp is newer than what's on disk
				if err != nil || (err == nil && ondiskTimestamp.Before(srcTimestamp)) {
					srcInfo.UserDefined[ReservedMetadataPrefixLower+TaggingTimestamp] = srcTimestamp.UTC().Format(time.RFC3339Nano)

	// Construct the final presigned URL.
	return nil
}

// preSignV2 - presign the request in following style.
// https://${S3_BUCKET}.s3.amazonaws.com/${S3_OBJECT}?AWSAccessKeyId=${S3_ACCESS_KEY}&Expires=${TIMESTAMP}&Signature=${SIGNATURE}.
func preSignV2(req *http.Request, accessKeyID, secretAccessKey string, expires int64) error {
	// Presign is not needed for anonymous credentials.
	if accessKeyID == "" || secretAccessKey == "" {

	Cached  bool // true only when we are requesting a cached response instead of hitting the disk for example ListBuckets() call.
}

// SetReplicaStatus sets replica status and timestamp for delete operations in ObjectOptions
func (o *ObjectOptions) SetReplicaStatus(st replication.StatusType) {
	o.DeleteReplication.ReplicaStatus = st
	o.DeleteReplication.ReplicaTimeStamp = UTCNow()
}

//
// Newer API response with policy timestamps is returned with query parameter
// `v=2` like:
//
// GET /minio/admin/v3/info-canned-policy?name={policyName}&v=2
//
// The newer API will eventually become the default (and only) one. The older
// response is to return only the policy JSON. The newer response returns
// timestamps along with the policy JSON. Both versions are supported for now,