TypeError in database launch error handle

[Matthew D. Wood]

openstack_dashboard.dashboards.project.databases.workflows.create_instance in populate_flavor_choices
TypeError: 'NoneType' object is not iterable

If there's an exception in openstack_dashboard/dashboards/project/databases/workflows/create_instance.py SetInstanceDetailsAction.flavors, the follow-on method will have a TypeError.

[code]
    @memoized.memoized_method
    def flavors(self, request):
        try:
            return api.trove.flavor_list(request)
        except Exception:
            LOG.exception("Exception while obtaining flavors list")
            self._flavors = []

    def populate_flavor_choices(self, request, context):
        flavor_list = [(f.id, "%s" % f.name) for f in self.flavors(request)]
        return sorted(flavor_list)
[code]

if self.flavors has an error, it will eventually return a None.

There's 2 options here:
A) return an empty list
B) redirect to another page

I have to believe that returning an empty list will be more confusing than a redirect, so I'd like to handle this with exceptions.handle.

[Openstack Gerrit (openstack-gerrit)]

Fix proposed to branch: master
Review: https://review.openstack.org/88413

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/88413
Committed: https://git.openstack.org/cgit/openstack/horizon/commit/?id=8e40c6ce915339553ce04fdb1590a8bac873c15a
Submitter: Jenkins
Branch: master

commit 8e40c6ce915339553ce04fdb1590a8bac873c15a
Author: woodm1979 <email address hidden>
Date: Thu Apr 17 13:35:40 2014 -0600

    Fixed TypeError in database launch error handle

    openstack_dashboard.dashboards.project.databases.workflows.create_instance
    in populate_flavor_choices

    TypeError: 'NoneType' object is not iterable

    If there's an exception in
    openstack_dashboard/dashboards/project/databases/workflows/create_instance.py
    SetInstanceDetailsAction.flavors, the follow-on method will have a
    TypeError.

    [code]
        @memoized.memoized_method
        def flavors(self, request):
            try:
                return api.trove.flavor_list(request)
            except Exception:
                LOG.exception("Exception while obtaining flavors list")
                self._flavors = []

        def populate_flavor_choices(self, request, context):
            flavor_list = [(f.id, "%s" % f.name) for f in self.flavors(request)]
            return sorted(flavor_list)
    [code]

    if self.flavors has an error, it will eventually return a None.

    There's 2 options here:
    A) return an empty list
    B) redirect to another page

    I have to believe that returning an empty list will be more confusing
    than a redirect, so I'd like to handle this with exceptions.handle.

    Change-Id: I9aff36875c26958ab8ef1f99828ed6113216c3c3
    Closes-Bug: 1306815