*`default_acl` - (Optional) The [canned GCS ACL](https://cloud.google.com/storage/docs/access-control#predefined-acl) to apply to future buckets. Must be set both `role_entity` and `predefined_acl` are not.
*`predefined_acl` - (Optional) The [canned GCS ACL](https://cloud.google.com/storage/docs/access-control#predefined-acl) to apply. Must be set if both `role_entity` and `default_acl` are not.
*`role_entity` - (Optional) List of role/entity pairs in the form `ROLE:entity`. See [GCS Bucket ACL documentation](https://cloud.google.com/storage/docs/json_api/v1/bucketAccessControls) for more details. Must be set if both `predefined_acl` and `default_acl` are not.