- release_tracks: [ALPHA, BETA, GA]

  help_text:
    brief: Updates the metadata of a Cloud Spanner a backup.
    description: Updates the metadata of a Cloud Spanner a backup.
    examples: |
      To update the backup metadata with an exact expiration date, run:

        $ {command} BACKUP_ID --instance=INSTANCE_NAME --expiration-date=2020-03-29T10:49:41Z

      To update the backup metadata with a retention period, run:

        $ {command} BACKUP_ID --instance=INSTANCE_NAME --retention-period=2w

  request:
    collection: spanner.projects.instances.backups
    method: 'patch'
    modify_request_hooks:
    - googlecloudsdk.api_lib.spanner.backups:ModifyUpdateMetadataRequest
  arguments:
    params:
    - group:
        mutex: true
        required: true
        params:
        - arg_name: expiration-date
          api_field: backup.expireTime
          help_text: |
            Expiration time of the backup, must be at least 6 hours and at most 366 days from
            the time of creation. See `$ gcloud topic datetimes` for information on
            date/time formats.
        - arg_name: retention-period
          api_field: backup.expireTime
          help_text: |
            Retention period of the backup relative from now, must be at least 6 hours and at most
            a year from the time of creation. See `$ gcloud topic datetimes` for information on
            duration formats.
    resource:
      help_text: The Cloud Spanner backup to update.
      spec: !REF googlecloudsdk.command_lib.spanner.resources:backup