Since the domain_id column is part of a uniqueness constraint and
it might now contain a nullable value, we actually store a special
value (as opposed to None) in the sql attribute so as to still use
the sql uniqueness constraint to ensure we do not have race
conditions in multi-process keystone configurations. So as to
continue to support a FK on the project.domain_id column, we create
a hidden domain ("the root of all domains"). In preparation for the
move to projects acting as domains, we also create a matching project
for this root. These special rows, and indeed the special domain_id
value stored, are entirely hidden within the sql driver and are not
exposed to the manager layer and above. The ability to store a project
domain_id of None is also added to the wrapper for legacy drivers.
In addition, one incorrectly written test relating to upcoming support
of projects as a domain had to be modified, since it started
passing prematurely, and the (now unused) driver base class method
for setting a domain_id is moved to the legacy V8 class.
Follow-on patches will build on this enable projects acting as domains,
which will have a null domain_id.
Co-Authored-By: Henry Nash <henryn@linux.vnet.ibm.com>
Partially-Implements: bp reseller
Change-Id: I4e5b9f3978482082c23f729d29bbdc701bc7c473
24b5dd021d