Comment 16 for bug 1479723

Reviewed: https://review.openstack.org/330800
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=e6da5b5546ae7e7df1a8946c33d57fec64252a35
Submitter: Jenkins
Branch: master

commit e6da5b5546ae7e7df1a8946c33d57fec64252a35
Author: Steve Baker <email address hidden>
Date: Wed Aug 31 18:05:44 2016 +1200

    Use enginefacade instead of db_session

    This change takes a gradual approach to fixing bug #1479723 by
    creating an enginefacade transaction_context, but mostly still using
    the legacy facade for getting the default session.

    Where a separate independent transaction is needed,
    db_context.writer.independent.using is used instead of get_session.

    The next change will decorate the db api functions with reader and
    writer so queries in a function are performed in a single transaction.

    Change-Id: If92788641d84b7314ed7ad1f8cb0e141fa1a8681
    Partial-Bug: #1479723