SQLAlchemy Query.all() can't raise NoResultFound exception

[Roman Podoliaka]

all() returns an empty list when no result is found, so there is no sense to except NoResultFound and return an empty list like the following code does:

        try:
            dns_qry = context.session.query(models_v2.DNSNameServer)
            return dns_qry.filter_by(subnet_id=subnet_id).all()
        except exc.NoResultFound:
            return []

We have a lot of such cases in our code which should be fixed.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/27687

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/27687
Committed: http://github.com/openstack/quantum/commit/daaf2b6d6502da4f185ed65a21a75ab2aab2d1b7
Submitter: Jenkins
Branch: master

commit daaf2b6d6502da4f185ed65a21a75ab2aab2d1b7
Author: Roman Podolyaka <email address hidden>
Date: Fri Apr 26 18:27:39 2013 +0300

    Fix usage of Query.all() and NoResultFound

    SQLAlchemy Query.all() method doesn't raise NoResultFound
    exception in case if no result is found but rather returns
    an empty list. So this pattern which is common for our code
    doesn't make sense and should be fixed:

        try:
            dns_qry = context.session.query(models_v2.DNSNameServer)
            return dns_qry.filter_by(subnet_id=subnet_id).all()
        except exc.NoResultFound:
            return []

    Fixes bug 1173131.

    Change-Id: I19b64eecd6edac0dba7dd0bf2ab32690c46e4f8b