google.pubsub_v1.types.Topic
Required. The updated topic object.
update_mask
google.protobuf.field_mask_pb2.FieldMask
Required. Indicates which fields in the provided topic to
update. Must be specified and non-empty. Note that if
``update_mask`` contains "message_storage_policy" but the
``message_storage_policy`` is not set in the ``topic``
provided above, then the updated value is determined by the
policy configured at the project or organization level.