This page discusses the metadata fields that are stored along with buckets in Cloud Storage.
Cloud Storage buckets have metadata associated with them. Metadata identifies properties of the bucket and specifies how the bucket should be handled when it's accessed.
Metadata is stored as
key: value pairs, where the
value can take a variety
of forms, including strings, arrays, or even nested
key:value pairs. For
example, the bucket name is a string, while a bucket Object Lifecycle Management
configuration is an array of rules in which each rule contains several child
key: value pairs.
The mutability of metadata varies:
Some you can only view.
Some you can only set when the bucket is first created, and cannot edit or remove.
Some you can add and edit, but not remove.
Some you can add, edit, and remove at any time.
The following metadata is set during bucket creation, and cannot be edited or removed:
The project the bucket is a part of
- A bucket's metageneration number uniquely identifies the metadata state of
the bucket. The metageneration number is
1at the time of bucket creation and increases each time you modify the bucket's metadata.
- A bucket's metageneration number uniquely identifies the metadata state of the bucket. The metageneration number is
Editable bucket metadata is metadata whose values you can typically modify at any time. In some cases, such as the bucket being subject to an organization policy constraint, there are restrictions on modifying certain metadata values.
1 This metadata cannot be viewed or managed using the XML API.
2 You can use the XML API to set this metadata during bucket creation, but not to view or manage this metadata.
- Learn how to view bucket metadata.
- Read more about object metadata.