In older versions of Kubernetes (at least pre-0.19, it's the earliest
this test will run unmodified on), Pods that depended on devices could be
restarted after the device plugin had been removed. Currently however,
this isn't possible, as during ContainerManager.GetResources(), we
attempt to DeviceManager.GetDeviceRunContainerOptions() which fails as
there's no cached endpoint information for the plugin type.
This commit therefore breaks apart the existing test into two:
- One active test that validates that assignments are maintained across
restarts
- One skipped test that validates the behaviour after GPUs have been
removed, in case we decide that this is a bug that should be fixed in
the future.
Prior to this change, the pod was not getting scheduled on the node as
we don't have a running scheduler in e2e_node. PodClient solves this
problem by manually assigning the pod to the node.
Most of these could have been refactored automatically but it wouldn't
have been uglier. The unsophisticated tooling left lots of unnecessary
struct -> pointer -> struct transitions.
