Week Ending November 6, 2022

Developer News

Code Freeze is coming, as is a mega-long list of merged changes and graduations.

The python-client developers are considering making major breaking changes, mainly for OpenAPI code. Add your feedback.

Release Schedule

Next Deadline: Code Freeze, Tuesday November 8th

Code Freeze is coming! This Tuesday at 5pm PST (November 9th 0100 UTC), we put a hold on all 1.26 merges that aren’t fixing failing tests. So get your last tweaks in! From here the deadlines are:

Test Freeze: November 15th
Docs Complete: November 29th
Release Day: December 6th

Patch releases are due out November 9th.

Featured PRs

#113274: [KEP-3521] Part 1: New Pod API .spec.schedulingGates

Pod objects have a fairly simple life cycle for their first few milliseconds. The API object is created, a scheduler sees that and tries to find a place to put it, if a node is found then the kubelet on that node wakes up and does Complicated Things. But what if you want to do some preparatory steps before all of this? Previously the only option was to make a validating webhook and reject the create in the first place, and arrange for the client to try again later when maybe the condition will be correct. This PR adds a better way, schedulingGates. This Spec field works kind of like finalizers but in reverse. When the scheduler sees a new unscheduled pod, it will check if the schedulingGates array is empty. If it’s not empty then no scheduling happens. Repeat any time the array changes. This means you can use mutating hooks on the create to inject a gate, wait until your condition to proceed is met, and then remove the gate and let things proceed as before. This opens up a lot of interesting possibilities with things like autoscaling, scheduler QoS, or fancy quota enforcement. If any of those sound up your alley, be sure to check out this alpha feature!

#109525: feat: make jsonpath wait logics consistent with condition

kubectl wait is one of the mainstays of “I just need to shim this one thing” shell scripts. Previously the --for=condition mode would behave as expected if the condition didn’t yet exist, it would keep waiting until the condition both existed and matched the requested state. But with --for=jsonpath, often used for sequencing load balancer and ingress setup, it would exit with an error if the path didn’t already exist. Now this behavior is unified so wait will stick around until the condition is met (the timeout expires) in both cases. This may fix some silent bugs in your scripts or it might be a good excuse to clean up any extra retry logic you built as a workaround.

#112011: Add ambiguous selector check to HPA

A potentially-breaking change for some folks, if multiple HPAs are configured against the same Pod, both with disable themselves and require you fix the configuration. Currently they would just both apply meaning whichever ran last would “win”. This does mean that when upgrading to 1.26, you should check for any such errors as your HPAs might have silently disabled themselves. You can also get a head-start on this now by checking for overly-broad selectors on your HPAs.

Other Merges

Add descriptions for shell completion in Bash
Try the alpha version of Windows host network
Default to warning about podsecurity if you’re enforcing it
APIserver persists lease names
Plaintext option for kubectl --explain
Allow specifying NUMA strategies in TopologyManger
Handle field ownership when the user specifies --server-side
Create etcd paths correctly and non-crashily
Shutdown nodeipam controller non-leakily
Allow auto-reload of encryption config and make sure KMS provider names are unique
Fix node address validation; backported
Disruption controller can patch stale pods status
Publish events when turning TopologyAwareHints on and off
Stop reusing stale VIPs on Windows
Metrics: add deleting_pods_total, stability framework custom collectors, AP&F borrowing metrics, cronjob skew metric
Don’t corrupt really long pod log lines
Fix getAllocatableCPUs
etcd resource versions are consistent for deleted objects
Validate admission CEL expressions
kube-proxy function naming cleanup
Prevent devicemanager startup crash
New disruption status for pods on failing kubelets
Add pod start SLI/SLO histogram
Rewrite less of iptables during syncs
Allow disabling nodeports on localhost
SPDY executor streams are cancellable

Test Overhaul: reusing/caching tests POC, naming of storage tests, code of storage tests, APIserver validation, NodeInclusionPolicy benchmarking, scheduler performance tests, large indexed job test, kubeadm reset, readWriteOncePod scheduling, APIserver tracing, disable cloud provider for tests, enabling NodeInclusionPolicy, podContainerManager, and improve formatting of e2e test output

Promotions

Non-graceful shutdown to Beta (otherwise known as “cut the power cord”)
JobTrackingWithFinalizers to GA, hopefully for the final time
NodeInclusionPolicy to Beta
ServiceInternalTrackingPolicy to GA
WindowsHostProcessContainers to GA
ProxyTerminatingEndpoints to Beta
EndpointSliceTerminatingCondition to GA
CSIMigrationVsphere to GA (time to migrate your storage, VMware users)
Azure CSI Migration to GA (same to you, Azure users)
RetroactiveStorageClass to Beta
DelegateFSGrouptoCSIDriver to GA
CPUManager to GA
Kubelet DeviceManger to GA
LoadBalancer mixed protocols to GA
LegacyServiceAccountTokenNoAutoGeneration to GA, and we have a new candidate for Longest Kubernetes Feature Name

Deprecated

Deprecate many unused kubectl run flags,like --filename and --timeout
Remove deprecated CRI v1alpha2 API and the last vestiges of dockershim

Version Updates

Update golang to 1.18.8 in 1.24 and 1.19.3 in 1.25 and 1.26

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