The context is used for cancellation and to support contextual logging.
In most cases, alternative *WithContext APIs get added, except for
NewIntegerResourceVersionMutationCache where code searches indicate that the
API is not used downstream.
An API break around SharedInformer couldn't be avoided because the
alternative (keeping the interface unchanged and adding a second one with
the new method) would have been worse. controller-runtime needs to be updated
because it implements that interface in a test package. Downstream consumers of
controller-runtime will work unless they use those test package.
Converting Kubernetes to use the other new alternatives will follow. In the
meantime, usage of the new alternatives cannot be enforced via logcheck
yet (see https://github.com/kubernetes/kubernetes/issues/126379 for the
process).
Passing context through and checking it for cancellation is tricky for event
handlers. A better approach is to map the context cancellation to the normal
removal of an event handler via a helper goroutine. Thanks to the new
HandleErrorWithLogr and HandleCrashWithLogr, remembering the logger is
sufficient for handling problems at runtime.
Several tests leaked goroutines. All of those get fixed where possible
without API changes. Goleak is used to prevent regressions.
One new test specifically covers shutdown of an informer and its event
handlers.
There are situations where it makes more sense to pass a logger through a
call chain, primarily because passing a context would imply that the call chain
should honor cancellation even though there is a different shutdown mechanism.
Using the *WithContext variants would cause additional overhead for
klog.NewContext, which hurts in particular for HandleCrash because that
function is typically a nop that doesn't actually need to log
anything. HandleCrashWithLogger avoids that overhead.
For HandleError that is less relevant because it always logs, but for the sake
of symmetry it also gets added.
Putting klog.Logger (= logr.Logger) into the public Kubernetes Go API is okay
because it's no longer realistic that these packages can ever drop the klog
dependency. Callers using slog as logger in their binary can use
https://github.com/veqryn/slog-context to store a slog.Logger in a context and
then call the *WithContext variants, klog.FromContext will be able to use it.
This is probably very rare, so there's no need for *WithSlog variants.
While at it, unit testing gets enhanced and logging in panic handlers gets
improved such that they are guaranteed to get a saner location when not
doing any caller skipping. Previously, this was undefined.
Previously, ValidateNodeSelector did not check that labels are valid. Now it
does for resource.k8s.io, regardless whether an object already was created with
invalid labels in an earlier Kubernetes release. Theoretically this is a
breaking change and could cause problems during an upgrade, but that is highly
unlikely in practice.
In contrast to node affinity, DRA does not ignore parse errors
(= uses NewNodeSelector, not NewLazyErrorNodeSelector), so invalid labels would
have been found instead of being silently ignored.
Even if some object has invalid labels, this only affects an alpha -> beta
upgrade which isn't guaranteed to work seamlessly.
Pruning of tests to the top-level test was added for jobs like
pull-kubernetes-unit which run many tests. For other, more focused jobs like
scheduler-perf benchmarking it would be nice to keep the more detailed
information, in particular because it includes the duration per test case.
The "disabled by label filter" message for benchmarks printed the pointer to
the filter string, not the filter string itself. This mistake gets avoided and
the code becomes simpler when not using pointers.
After removing a pod in port-forward test we wait for an error from POST
request. Since the POST doesn't have a timeout it hangs indefinitely, so
instead we're hitting a DefaultPodDeletionTimeout. To make sure the POST
fails this adds a timeout to ensure we'll always get that expected
error, rather than nil.
Signed-off-by: Maciej Szulik <soltysh@gmail.com>
