Nova not always using get to access driver capabilites dict

[Eric Berglund]

When accessing the capabilities dict [1], nova should be using dict.get(). Since many compute drivers override the capabilities dictionary,

capabilites['capability']

will fail with a KeyError if their dictionary has not been updated to include the capability. By using get() it will default instead of throwing the KeyError.

[1] https://github.com/openstack/nova/blob/5251f18d87/nova/virt/driver.py#L124-L134

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/539715

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/539715
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=2dd322a64291c20da33f28fd5c302ff27e70eae4
Submitter: Zuul
Branch: master

commit 2dd322a64291c20da33f28fd5c302ff27e70eae4
Author: esberglu <email address hidden>
Date: Wed Jan 31 16:29:57 2018 -0600

    Use dict.get() when accessing capabilities dict

    Many compute drivers override the driver capabilities dict [1]. The
    code should be using dict.get() to avoid throwing KeyErrors if the
    overriding dictionaries do not have the corresponding keys. If the
    key is not found it will be assumed the the capability is not supported
    and default to false. This ensures that no drivers are broken because
    they are missing a capability.

    [1] https://github.com/openstack/nova/blob/5251f18d87/nova/virt/driver.py#L124-L134

    Change-Id: I1fa04fa110f2c65e10c065c61f2f0f58c1fad646
    Closes-Bug: #1746608

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 18.0.0.0b1 development milestone.