versionId

Version ID of the object.

If you enable versioning for a bucket, Amazon S3 automatically generates a unique version ID for the object being stored. Amazon S3 returns this ID in the response. When you enable versioning for a bucket, if Amazon S3 receives multiple write requests for the same object simultaneously, it stores all of the objects. For more information about versioning, see Adding Objects to Versioning-Enabled Buckets in the Amazon S3 User Guide. For information about returning the versioning state of a bucket, see GetBucketVersioning.

This functionality is not supported for directory buckets.