The main advantage is that waiting on channels creates a causal relationship
between goroutines which is visible to synctest. When a controller in a
synctest bubble does a WaitFor in a test's background goroutine for the
controller, the test can use synctest.Wait to wait for completion of cache
sync, without requiring any test specific "has controller synced" API. Without
this, the test had to poll or otherwise wait for the controller.
The polling in WaitForCacheSync moved the virtual clock forward by a random
amount, depending on how often it had to check in wait.Poll. Now tests can be
written such that all events during a test happen at a predictable time. This
will be demonstrated in a separate commit for the
pkg/controller/devicetainteviction unit test.
The benefit for normal production is immediate continuation when the last
informer is synced (not really a problem, but still...) and more important,
nicer logging thanks to the names associated with the thing that is being
waited for. The caller decides whether logging is enabled or disabled and
describes what is being waited for (typically informer caches, but maybe also
event handlers or even something else entirely as long as it implements the
DoneChecker interface).
Before:
Waiting for caches to sync
Caches are synced
After:
Waiting for="cache and event handler sync"
Done waiting for="cache and event handler sync" instance="SharedIndexInformer *v1.Pod"
Done waiting for="cache and event handler sync" instance="SharedIndexInformer *v1.ResourceClaim"
Done waiting for="cache and event handler sync" instance="SharedIndexInformer *v1.ResourceSlice"
Done waiting for="cache and event handler sync" instance="SharedIndexInformer *v1.DeviceClass"
Done waiting for="cache and event handler sync" instance="SharedIndexInformer *v1alpha3.DeviceTaintRule"
Done waiting for="cache and event handler sync" instance="SharedIndexInformer *v1.ResourceClaim + event handler k8s.io/kubernetes/pkg/controller/devicetainteviction.(*Controller).Run"
Done waiting for="cache and event handler sync" instance="SharedIndexInformer *v1.Pod + event handler k8s.io/kubernetes/pkg/controller/devicetainteviction.(*Controller).Run"
Done waiting for="cache and event handler sync" instance="SharedIndexInformer *v1alpha3.DeviceTaintRule + event handler k8s.io/kubernetes/pkg/controller/devicetainteviction.(*Controller).Run"
Done waiting for="cache and event handler sync" instance="SharedIndexInformer *v1.ResourceSlice + event handler k8s.io/kubernetes/pkg/controller/devicetainteviction.(*Controller).Run"
The "SharedIndexInformer *v1.Pod" is also how this appears in metrics.
Kubernetes-commit: fdcbb6cba9a04c028b158bf66d505df7431f63fe
This improves logging and enables more informative waiting for cache sync in a
following commit. It addresses one klog.TODO in the Reflector.
The RealFIFOOptions and InformerOptions structs get extended the same way as
DeltaFIFOOptions before: a logger may be set, but it's not required. This is
not an API break.
That the name has to be passed separately is a bit annoying at first glance
because it could also be set directly on the logger through WithName, but
keeping it separate is better:
- name can be set without providing a logger
- name can be defaulted
- less code in the caller when passing through a logger and adding
the name only in the field
- last but not least, extracting the name is not supported in a portable
manner by logr
All in-tree references in production code get updated.
While at it, logging in the fifos gets updated to follow best practices: if
some code encounters an abnormal situation and then continues, it should use
utilruntime.HandleErrorWithLogger instead of normal error logging.
Existing "logger" fields get moved to the top because that is a more common
place for such a read-only field.
Kubernetes-commit: 45251e5f654e6c052659d110cd721f9fbe185191
Signed-off-by: Min Jin <minkimzz@amazon.com>
Update staging/src/k8s.io/client-go/tools/cache/the_real_fifo.go
optimizing fifo loop
Co-authored-by: Marek Siarkowicz <marek.siarkowicz@protonmail.com>
Signed-off-by: Min Jin <minkimzz@amazon.com>
refactoring PopBatch to accept []Delta
Signed-off-by: Min Jin <minkimzz@amazon.com>
Kubernetes-commit: 611b4c1408f529de4d4e94e6dd33be2ed1df9276
Logically a cache.Queue.AddIfNotPresent means that the informer can move
back in time since an older item is placed after newer items. The
alternative of placing errors at the head of the queue leads to
indefinite memory growth and repeated failures on retry.
Luckily this behavior was behind RetryOnError, which was always set to
false and impossible for normal users to set to true. By removing the
function and setting, impacted users (none found in a github search)
will get a compile failure.
Kubernetes-commit: 8e77ac000131019d5aa49c19aa1f477f6dac4d59
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.
Kubernetes-commit: 4638ba971661497b147906b8977ae206c9dd6e44
While refactoring the backoff manager to simplify and unify the code
in wait a race condition was encountered in
TestSharedInformerWatchDisruption. The new implementation failed
because the fake clock was not propagated to the backoff managers
when the reflector was used in a controller. After ensuring the
mangaers, reflector, controller, and informer shared the same
clock the test needed was updated to avoid the race condition by
advancing the fake clock and adding real sleeps to wait for
asynchronous propagation of the various goroutines in the controller.
Due to the deep structure of informers it is difficult to inject
hooks to avoid having to perform sleeps. At a minimum the FakeClock
interface should allow a caller to determine the number of waiting
timers (to avoid the first sleep).
Kubernetes-commit: 91b3a81fbd916713afe215f7d701950e13a02869
* Add tracker types and tests
* Modify ResourceEventHandler interface's OnAdd member
* Add additional ResourceEventHandlerDetailedFuncs struct
* Fix SharedInformer to let users track HasSynced for their handlers
* Fix in-tree controllers which weren't computing HasSynced correctly
* Deprecate the cache.Pop function
Kubernetes-commit: 8100efc7b3122ad119ee8fa4bbbedef3b90f2e0d
Add an annotation that can be added to the exampleType passed to
NewReflector to indicate the expected type for the Reflector. This is
useful for types such as unstuctured.Unstructured, which, when used with
a dynamic informer, do not have their TypeMeta filled in.
Signed-off-by: Andy Goldstein <andy.goldstein@redhat.com>
Kubernetes-commit: 474fc8c5234000bce666a6b02f7ffbb295ef135f
- Run hack/update-codegen.sh
- Run hack/update-generated-device-plugin.sh
- Run hack/update-generated-protobuf.sh
- Run hack/update-generated-runtime.sh
- Run hack/update-generated-swagger-docs.sh
- Run hack/update-openapi-spec.sh
- Run hack/update-gofmt.sh
Signed-off-by: Davanum Srinivas <davanum@gmail.com>
Kubernetes-commit: a9593d634c6a053848413e600dadbf974627515f
TransformingInfomer is like a regular Informer, but allows for applying
custom transform functions on the objects received via list/watch API calls.
Kubernetes-commit: efd3490076c391823095b4c8bd6e847ae18eb012
Currently there is no way to specify WatchListPageSize used by Controller. This PR adds a field that can be used to specify this.
Change-Id: I241454a45dd94d3ea65a91b297f530e217f843aa
Kubernetes-commit: 43f5afe1a1dd058a2564cd3b2f330fc2a401f607
When creating an informer, this adds a way to add custom error handling, so that
Kubernetes tooling can properly surface the errors to the end user.
Fixes https://github.com/kubernetes/client-go/issues/155
Kubernetes-commit: 435b40aa1e5c0ae44e0aeb9aa6dbde79838b3390
Background:
Before this change, DeltaFIFO emits the Sync DeltaType on Resync() and
Replace(). Seperately, the SharedInformer will only pass that event
on to handlers that have a ResyncInterval and are due for Resync. This
can cause updates to be lost if an object changes as part of the Replace(),
as it may be incorrectly discarded if the handler does not want a Resync.
What this change does:
Creates a new DeltaType, Replaced, which is emitted by DeltaFIFO on
Replace(). For backwards compatability concerns, the old behavior of
always emitting Sync is preserved unless explicity overridden.
As a result, if an object changes (or is added) on Replace(), now all
SharedInformer handlers will get a correct Add() or Update()
notification.
One additional side-effect is that handlers which do not ever want
Resyncs will now see them for all objects that have not changed during
the Replace.
Kubernetes-commit: ca1eeb99b530a6d76b464dad545abc18d4508c49
2. Remove staging/src/k8s.io/client-go/tools/cache from .golint_failures;
3. Fix some typo from comments.
Kubernetes-commit: 0e0e1f7daba0a6ae6dd59df0a1bb643c323ad8cb
