There's a potential deadlock when creating the first LB in a new
project. The query that creates an empty quota object for the project
may have triggered a deadlock in the DB, this deadlock should have been
handlded by an oslo_db.api.wrab_db_retry decorator but the decorated
function was incorrect called: the DB session must begin in the
decorated function and not in the caller.
If begin is called by the caller, in case of retry sqlalchemy will
complain that the session was not correctly restarted after a rollback.
Closes-Bug: #2038798
Change-Id: Iec1f8f8f61d77640d4a33d7ffb62925f7e860286
Gregory Thiemonge
333f035ed2