Comment 6 for bug 1708260

Reviewed: https://review.openstack.org/491487
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=c95cd011d01f7e5cbd10346223be995f6507f9e7
Submitter: Jenkins
Branch: stable/ocata

commit c95cd011d01f7e5cbd10346223be995f6507f9e7
Author: Chris Dent <email address hidden>
Date: Wed Aug 2 21:21:12 2017 +0100

    [placement] Require at least one allocation when PUT

    When doing a PUT to /allocations/{consumer_uuid} if the list of
    allocations is empty there is a 500 error coming from an uncaught
    IndexError.

    Adjust the schema to require at least one allocation. If no allocations
    are provided in the list, the response will be a 400.

    This doesn't require a microversion because it is changing a 500 to
    a useful response.

    Change-Id: I361fa1e534d7b20c985558e272b672b84c6fe439
    Closes-Bug: #1708260
    (cherry picked from commit 9155da345e5d6d1aee293bc66f746da52bca4c79)