Week Ending November 8, 2020

Developer News

Kubectl is moving the last bits to staging repos, which means that contributions to kubectl need to move there in the future.

In order to avoid accidental disclosure of private data, the Data Management WG is planning to add field tags across many APIs. Comment now if you have any feedback.

We’re participating in the GitHub Kudos beta, so thank a contributor today!

Release Schedule

Next Deadline: CODE FREEZE November 12

Working on a 1.20 feature? Get your PRs merged by EOD Thursday, or get delayed to 1.21. If you need to postpone, the Release Team can change your milestones. After this, it’s all about getting tests to pass.

Patch releases 1.19.4, 1.18.11, and 1.17.14 are planned for Wednesday this week.

Featured PRs

#94115: kubelet: respect exec probe timeouts

A relatively small fix, correctly checking for timeout errors during an exec probe, however this change pushes the dreaded Correct But A Compatibility Change button. All Kubernetes users are advised to review their usage of exec checks in readiness, liveness, and startup probes to see if you have a timeout set that will cause your checks to fail now. A default-true ExecProbeTimeout feature gate has been added to restore the old behavior, however it will only be maintained until 1.22 so proactive action is recommended.

#96097: Introduce a simple datapolicy library

As a follow up to the recent security issues with tokens being logged, we have a prototype for a data policy library, and a second PR adding an example log filter that uses it. The hope is this can prevent future data leakage by tagging data at the struct level. Currently this is implemented in a highly dynamic way using reflect, so if your subsystems will make heavy use of it you may want to do some performance testing. If you have any feedback about the current implementation or questions about how to integrate with it, please contact SIG-APIMachinery or respond on k-dev.

The heart of the new library is a datapolicy:"type" struct tag that will be used to mark struct fields that contain a certain type of sensitive data, such as datapolicy:"password" or datapolicy:"apikey". A final list of standard type names has not yet been created. The data policy library exposes a Validate() method which takes any value and returns an array of all the data policy labels on fields in that object, recursively validating sub-objects below the one passed in. The simplest use cases can check if len() > 0 and refuse to process or output the value, but specific types can be allowed by ignoring them in the array.

Other Merges

• Add the api-extensions category to the API, for mutating admission configs, CRDs, and all the other customizable stuff
• RootCAConfigMap is enabled by default, causing the controller to publish a configmap with APIserver connection certs to every namespace
• You can set the size of memory-backed volumes
• Since TokenRequest is now GA, require a bunch of APIserver flags for managing cert issuing
• Bypass kube-proxy and use the Load Balancer directly via LoadBalancerIPMode
• kubectl warns you if a resource gets deleted during apply, and if you try to copy a nonexistant file to a pod
• The APIserver maintains a lease object to identify itself for upgrades and migrations
• DefaultPreemption evaluates a small pool of nodes in large clusters, speeding it up in cases when many nodes have preemptable pods
• The APIserver will update storageversions before serving write requests, permitting safe storage migration
• EndpointSlices get serving and ``terminating` conditions so you can distinguish between an endpoint that’s nonexistant and one that’s shutting down
• etcd healtcheck timeout is configurable
• Turn on service-account-extend-token-expiration metric by default
• Fix the conntrack entry clearing bug introduced by the last attempt to fix nodeports
• APF metrics all use snake_case
• Add a timeout for TokenReview
• The Scheduler will honor LoclaStorageCapacityIsolation (backported)
• Support multiple Azure standard load balancers in one cluster
• Don’t schedule pods that don’t have the right labels, even if they do have topologySpreadConstraints
• New e2e test to validate the VolumeSnapshot finalizer
• Internationalization cleanup for kubectl commands
• CRD non-nullable map fields automatically get default values
• kubectl diff passes arguments to external diff tools

Promotions

• kubectl debug to beta, replacing kubectl alpha debug (the EphemeralContainers feature gate is still alpha status)

Deprecated

• StreamingProxyRedirects are being deprecated, starting by disabling --redirect-container-streaming
• kubectl --delete-local-data is deprecated in favor of --delete-emptydir-data

Last Week In Kubernetes Development (LWKD) is a product of multiple contributors participating in Kubernetes SIG Contributor Experience. All original content is licensed Creative Commons Share-Alike, although linked content and images may be differently licensed. LWKD does collect some information on readers, see our privacy notice for details.

You may contribute to LWKD by submitting pull requests or issues on the LWKD github repo.