This moves from forcefully deleting pods to deleting pods in a
graceful manner from the API Server. It waits for the pod to
get to a terminal status prior to deleting the pod from api
server.
Pods can be updated outside of VK. Right now, if this happens, pod
status updates are dropped because the resourceversion from the
provider will mismatch with what's on the server, breaking
pod status updates.
Since we're the only ones writing to the pod status, we
can do a blind overwrite.
This removes the legacy sync provider interface. All new providers
are expected to implement the async NotifyPods interface.
The legacy sync provider interface creates complexities around
how the deletion flow works, and the mixed sync and async APIs
block us from evolving functionality.
This collapses in the NotifyPods interface into the PodLifecycleHandler
interface.
We poll legacy providers for their pod(s) status periodically. This is because
we have no way of knowing when the pod is updated. If the pod somehow goes
missing in the provider, that state must be handled. Currently, we update
API server, and mark the pod as failed, or ignore it.
We introduce a map that can be used to store the pod status. In this,
we do not need to call GetPodStatus immediately after NotifyPods
is called. Instead, we stash the pod passed via notifypods
as in a map we can access later. In addition to this, for legacy
providers, the logic to merge the pod, and the pod status is
hoisted up to the loop.
It prevents leaks by deleting the entry in the map as soon
as the pod is deleted from k8s.
This moves to a model where any time that pods are given to a
provider, it uses a DeepCopy, as opposed to a reference. If the
provider mutates the pod, it prevents it from causing issues
with the informer cache.
It has to use reflect instead of comparing the hashes because
spew prints DeepCopy'd data structures ever so slightly differently.
* Fix error handling for delete pod
- Error handling was looking for a k8s error from the provider, but
providers should be using errdefs.
- Error handling was returning early if pod was not found and deleting
from k8s in all other cases.
* Don't run unit tests twice
* Move tracing exporter registration
This doesn't belong in the library and should be configured by the
consumer of the opencensus package.
* Rename `vkublet` package to `node`
`vkubelet` does not convey any information to the consumers of the
package.
Really it would be nice to move this package to the root of the repo,
but then you wind up with... interesting... import semantics due to the
repo name... and after thinking about it some, a subpackage is really
not so bad as long as it has a name that convey's some information.
`node` was chosen since this package deals with all the semantics of
operating a node in Kubernetes.
