// S3 object version ID
	AmzVersionID    = "x-amz-version-id"
	AmzDeleteMarker = "x-amz-delete-marker"

	// S3 object tagging
	AmzObjectTagging = "X-Amz-Tagging"
	AmzTagCount      = "x-amz-tagging-count"
	AmzTagDirective  = "X-Amz-Tagging-Directive"

	// S3 transition restore
	AmzRestore            = "x-amz-restore"
	AmzRestoreExpiryDays  = "X-Amz-Restore-Expiry-Days"

			HandlerFunc(s3APIMiddleware(api.GetObjectTaggingHandler, traceHdrsS3HFlag)).
			Queries("tagging", "")
		// PutObjectTagging
		router.Methods(http.MethodPut).Path("/{object:.+}").
			HandlerFunc(s3APIMiddleware(api.PutObjectTaggingHandler, traceHdrsS3HFlag)).
			Queries("tagging", "")
		// DeleteObjectTagging
		router.Methods(http.MethodDelete).Path("/{object:.+}").

| `minio_cluster_replication_proxied_get_tagging_requests_total` | (_Site Replication Only_)Number of GET tagging requests proxied to replication target                          |

	DeleteMarker            bool // Is only set in DELETE operations for delete marker replication
	CheckDMReplicationReady bool // Is delete marker ready to be replicated - set only during HEAD
	Tagging                 bool // Is only in GET/HEAD operations to return tagging metadata along with regular metadata and body.

	UserDefined         map[string]string   // only set in case of POST/PUT operations

	"encryption",
	"legal-hold",
	"lifecycle",
	"location",
	"logging",
	"notification",
	"partNumber",
	"policy",
	"requestPayment",
	"response-cache-control",
	"response-content-disposition",
	"response-content-encoding",
	"response-content-language",
	"response-content-type",
	"response-expires",
	"retention",
	"select",
	"select-type",
	"tagging",
	"torrent",
	"uploadId",
	"uploads",
	"versionId",

	Encryption   Encryption      `xml:"Encryption,omitempty"`
	Prefix       string          `xml:"Prefix,omitempty"`
	StorageClass string          `xml:"StorageClass,omitempty"`
	Tagging      *tags.Tags      `xml:"Tagging,omitempty"`
	UserMetadata []MetadataEntry `xml:"UserMetadata"`
}

// OutputLocation specifies bucket where object needs to be restored
type OutputLocation struct {

uniqueness over space and time and are computationally difficult to guess. They are globally unique identifiers which can be locally generated without contacting a global registration authority. UUIDs are intended as unique identifiers for both mass tagging objects with an extremely short lifetime and to reliably identifying very persistent objects across a network.

When you PUT an object in a versioning-enabled bucket, the noncurrent version is not overwritten. The following figure shows that...

	ReplicationSsecChecksumHeader:                               ReplicationSsecChecksumHeader,
	// Add more supported headers here.
}

// isDirectiveValid - check if tagging-directive is valid.
func isDirectiveValid(v string) bool {
	// Check if set metadata-directive is valid.
	return isDirectiveCopy(v) || isDirectiveReplace(v)
}

// Check if the directive COPY is requested.

 *  Fix: Don't log gzipped data in the logging interceptor.
 *  Fix: Don't resolve DNS addresses when connecting through a SOCKS proxy.
 *  Fix: Drop the synthetic `OkHttp-Selected-Protocol` response header.
 *  Fix: Support 204 and 205 'No Content' replies in the logging interceptor.
 *  New: Add `Call.isExecuted()`.


## Version 2.6.0

_2015-11-22_

 *  **New Logging Interceptor.** The `logging-interceptor` subproject offers

func cleanMetadata(metadata map[string]string) map[string]string {
	// Remove STANDARD StorageClass
	metadata = removeStandardStorageClass(metadata)
	// Clean meta etag keys 'md5Sum', 'etag', "expires", "x-amz-tagging".
	return cleanMetadataKeys(metadata, "md5Sum", "etag", "expires", xhttp.AmzObjectTagging, "last-modified", VersionPurgeStatusKey)
}

// Filter X-Amz-Storage-Class field only if it is set to STANDARD.