The rescue API should handle NotImplementedError

[Matt Riedemann]

There are several nova virt drivers that don't implement the rescue API, but the os compute API doesn't handle NotImplementedError, it returns a 400 instead of a 501.

https://wiki.openstack.org/wiki/HypervisorSupportMatrix

The API could be tightened up a bit to return a 501 instead like how the pause admin action is handling NotImplementedError.

[Matt Riedemann (mriedem)]

The 4th bullet here should come into play when changing the error code for the API:

https://wiki.openstack.org/wiki/APIChangeGuidelines#Generally_Considered_OK

"Changing an error response code to be more accurate"

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/77736

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/77736
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=f3f46b532c528c31fbcdc0d18b18105c42a0d74c
Submitter: Jenkins
Branch: master

commit f3f46b532c528c31fbcdc0d18b18105c42a0d74c
Author: Leandro I. Costantino <email address hidden>
Date: Mon Mar 3 21:09:52 2014 -0300

    Rescue API handle NotImplementedError

    There are several nova virt drivers that don't implement the rescue API,
    but the os compute API doesn't handle NotImplementedError,
    it returns a 400 instead of a 501.

    The patch add the proper logic to return a 501 instead.

    Change-Id: Ia649c4dadd50985efed631ce8f3e4b212646766e
    Closes-Bug: #1287367