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update Mount propagation version in comment
**What this PR does / why we need it**:
Mount propagation feature was moved to beta in PR [#59252](https://github.com/kubernetes/kubernetes/pull/59252)， so update the comment.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#60657
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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log enabled admission controller in order
After switching to --enable-admission-plugins/--disable-admission-plugins, some admission controller may start silently. And these admission controllers may modify or forbid objects. This pull request does a lot of help for admin to trouble shooting.
/assign @hzxuzhonghu @sttts
**Release note**:
```release-note
NONE
```
Local cluster is leaking memory due to mutation detector being enabled.
In addition there is no warning in the logs that this could be the
issue.
Added a log warning when this feature is enabled to make debugging this
issue easier for other cases of this.
Fixed import ordering as per @liggitt
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Bump etcd server patch version to 3.2.16
etcd 3.2.16 contains a critical fix for HA clusters: https://github.com/coreos/etcd/pull/9281
Also, update newly added tests to use `REGISTRY` make variable.
Release note:
```release-note
Upgrade the default etcd server version to 3.2.16
```
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Update README.md of sample-apiserver.
Mention CRDs as option.
Link to CRD vs Aggr. docs.
Mention apiserver-builder as alternative.
```release-note
NONE
```
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Prevent webhooks from affecting admission requests for WebhookConfiguration objects
**What this PR does / why we need it**:
As it stands now webhooks can be added to the system which make it impossible for a user to remove that webhook, or two webhooks could be registered which make it impossible to remove each other.
The first commit of this will add a test to make sure webhook deletion is never blocked by a webhook. This test will fail until the second commit is added which will prevent webhooks from affecting admission requests for ValidatingWebhookConfiguration and MutatingWebhookConfiguration objects in the admissionregistration.k8s.io group
- [x] Test that webhook deletion is never blocked by a webhook ([test fails before second commit](https://k8s-gubernator.appspot.com/build/kubernetes-jenkins/pr-logs/pull/59840/pull-kubernetes-e2e-gce/23731/))
- [x] Prevent webhooks from being called on admission requests for [Validating|Mutating]WebhookConfiguration objects
- [x] Document this new behavior maybe in another PR
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Part of fixing #59124 (Verifies that it can remove the broken webhook.)
**Release note**:
```release-note
ValidatingWebhooks and MutatingWebhooks will not be called on admission requests for ValidatingWebhookConfiguration and MutatingWebhookConfiguration objects in the admissionregistration.k8s.io group
```
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Fix kubectl completion so that file names are listed
**What this PR does / why we need it**:
This PR fixes kubectl completion so that file names are listed with `--filename`. I tested in bash and zsh. This problem is caused by spf13/cobra#520, so I updates vendor github.com/spf13/cobra to just before that commit.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#60517
**Special notes for your reviewer**: @janetkuo @mengqiy @eparis
**Release note**:
```release-note
NONE
```
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[e2e] Fix panicing ingress jobs
**What this PR does / why we need it**:
When a nil error is passed into IsProbableEOF(), test will panic. Ref https://github.com/kubernetes/kubernetes/issues/60381#issuecomment-369353511.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#60381
**Special notes for your reviewer**:
/assign @shyamjvs
cc @krzyzacy
**Release note**:
```release-note
NONE
```
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Allow update/patch of CRs while CRD is terminating
Fixes#60538
Update/patch need to be allowed so finalizers can act on custom resources for terminating CRDs
```release-note
Fixes potential deadlock when deleting CustomResourceDefinition for custom resources with finalizers
```
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Use consts defined in api instead of defining another ones.
**What this PR does / why we need it**:
empty_dir defines some consts. There are already similar consts in api types. So remove the local ones in empty_dir.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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remove unused function negotiate() and writeYAML()
**What this PR does / why we need it**:
remove unused function negotiate() and writeYAML() in k8s.io/apiserver/pkg
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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cloud-controller-manager get /healthz to wait for apiserver to be healthy
**What this PR does / why we need it**:
currently cloud-controller-manager use `restclient.ServerAPIVersions()` to wait for apiserver to be healthy.
Remove ServerAPIVersions and make use of /healthz as all other components do.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#60288
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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Remove dep-reviewers
**What this PR does / why we need it**:
The dep-reviewers group seems to get assigned PRs early the the review process. However, most code changes should be reviewed in the importing part of the code base first, and then assigned to an approver after.
By removing the reviewers group, the approvers plugin will still suggest assigning to an approver, but won't assign for review when the PR is initially opened.
**Release note**:
```release-note
NONE
```
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code-gen: output golint compliant 'Generated by' comment
New PR instead of reopening #58115 because /reopen did not work.
This won't be ready to merge until the upstream https://github.com/kubernetes/gengo/pull/94 merges. Once that merges, the second commit will be changed to godep-save.sh and update-staging-godeps.sh, and the last commit will be changed to update-all.sh
The failing test is due to the upstream changes not being merged yet
```devel-release-note
Go code generated by the code generators will now have a comment which allows them to be easily identified by golint
```
Fixes#56489
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fix some syntax related errors
**What this PR does / why we need it**:
fix some syntax related errors
**Special notes for your reviewer**:
None
```release-note
NONE
```
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Serve OpenAPI spec with single /openapi/v2 endpoint
**What this PR does / why we need it**:
We are deprecating format-separated endpoints (`/swagger.json`, `/swagger-2.0.0.json`, `/swagger-2.0.0.pb-v1`, `/swagger-2.0.0.pb-v1.gz`) for OpenAPI spec, and switching to a single `/openapi/v2` endpoint in Kubernetes 1.10. The design doc and deprecation process are tracked at: https://docs.google.com/document/d/19lEqE9lc4yHJ3WJAJxS_G7TcORIJXGHyq3wpwcH28nU
Requested format is specified by setting HTTP headers
header | possible values
-- | --
Accept | `application/json`, `application/com.github.proto-openapi.spec.v2@v1.0+protobuf`
Accept-Encoding | `gzip`
This PR changes dynamic_client (and kubectl as a result) to use the new endpoint. The old endpoints will remain in 1.10 and 1.11, and get removed in 1.12.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
action required: Deprecate format-separated endpoints for OpenAPI spec. Please use single `/openapi/v2` endpoint instead.
```
/sig api-machinery
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Require boilerplate on Bazel Skylark source files
**What this PR does / why we need it**: `.bzl` files are also source code, so they should probably have the boilerplate text too.
**Release note**:
```release-note
NONE
```
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Introduce buffered audit backend
This is a copy from https://github.com/kubernetes/kubernetes/issues/53006 with comments addressed, since @hzxuzhonghu cannot work on this right now and the code freeze is close. Thanks @hzxuzhonghu for the contribution!
This is the first PR to fix https://github.com/kubernetes/kubernetes/issues/53006 and then https://github.com/kubernetes/kubernetes/issues/53020
This PR introduces a new audit backend, that batches incoming audit events and sends these batches to the underlying audit backend. This new backend is designed to replace existing batching webhook backend and allow to use batching with log backend, to solve the performance issues.
@sttts @ericchiang @CaoShuFeng @tallclair would really appreciate your review
```release-note
Buffered audit backend is introduced, to be used with other audit backends.
```
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Update vendor spf13/cobra to fix completion error in bash 3
**What this PR does / why we need it**: This PR updates vendor spf13/cobra to fix completion error in bash 3.
/ref spf13/cobra#628
/cc @eparis
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixeskubernetes/kubectl#121, kubernetes/kubernetes#29322, kubernetes/kubernetes#32676.
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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Introduce External Metrics API
**What this PR does / why we need it**:
Introduce External Metrics API
This PR introduces External Metrics API which has been proposed: xref https://github.com/kubernetes/community/pull/1802
**Release note**:
```release-note
NONE
```
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Add comments about potential race in delta fifo
**What this PR does / why we need it**:
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
/sig api-machinery
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Promote configurable pod resolv.conf to Beta and add an e2e test
**What this PR does / why we need it**:
Feature issue: https://github.com/kubernetes/features/issues/504
There is no semantic changes. `CustomPodDNS` feature gate will be turned on by default.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#56521
**Special notes for your reviewer**:
/assign @bowei @thockin
**Release note**:
```release-note
Adds BETA support for `DNSConfig` field in PodSpec and `DNSPolicy=None`.
```
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Implement a stub server printer for CRDs
This wires up TableConvertor to CRDs and puts a basic implementation in place for custom paths. However, since our OpenAPISchema can't store OpenAPI extension fields there is no way to expose the custom column piece that get.go supports today (`x-kubernetes-print-columns`). That piece can be implemented separately and needs discussion.
As this is purely exposing the default interface, very low risk. Will add an e2e test that covers this under a registered CRD.
@soltysh @sttts @kubernetes/sig-api-machinery-pr-reviews
A couple of options for wiring up the actual definition:
1. add a new "extensions" map to spec.validation
1. Downside: won't handle future child nested fields, not the correct schema
2. try to change the OpenAPISchema3 field to support extensions
1. Would require a breaking protobuf change, is also very difficult
2. Could store the entire schema as opaque JSON and then parse on load (might be the right thing anyway)
3. Support this as an annotation in 1.11 - `alpha.customresource.k8s.io/x-kubernetes-print-columns` like the CLI
Part of #58536
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Adding credentials support for k8s core CSI
PR implements changes proposed in: https://github.com/kubernetes/community/pull/1816
```release-note
CSI now allows credentials to be specified on CreateVolume/DeleteVolume, ControllerPublishVolume/ControllerUnpublishVolume, and NodePublishVolume/NodeUnpublishVolume operations
```
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Fixes for HTTP/2 max streams per connection setting
**What this PR does / why we need it**:
This PR makes two changes. One is to introduce a parameter
for the HTTP/2 setting that an api-server sends to its clients
telling them how many streams they may have concurrently open in
an HTTP/2 connection. If left at its default value of zero,
this means to use the default in golang's HTTP/2 code (which
is currently 250; see https://github.com/golang/net/blob/master/http2/server.go).
The other change is to make the recommended options for an aggregated
api-server set this limit to 1000. The limit of 250 is annoyingly low
for the use case of many controllers watching objects of Kinds served
by an aggregated api-server reached through the main api-server (in
its mode as a proxy for the aggregated api-server, in which it uses a
single HTTP/2 connection for all calls proxied to that aggregated
api-server).
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#60042
**Special notes for your reviewer**:
**Release note**:
```release-note
Introduced `--http2-max-streams-per-connection` command line flag on api-servers and set default to 1000 for aggregated API servers.
```
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Add a metric exposing number of objects per type
Fix#51953
Adds a goroutine that periodically checks the count of objects in etcd and publishes a metric with this data.
```release-note
APIserver backed by etcdv3 exports metric showing number of resources per kind
```
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apiserver: fix testing etcd config in preparation for etcd 3.2.16+
The AuthToken must be set, also in non-https mode. Otherwise, etcd refuses to start.
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audit/request.go remove inaccurate TODO and fix typo
**What this PR does / why we need it**:
remove one inaccurate `TODO` and fix a typo
**Release note**:
```release-note
NONE
```
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Allow to specify categories for custom resources
Allow to specify categories for custom resources so that we can get it working with `kubectl get all`.
Adds a new field `Categories` in the CRD spec.
**Release note**:
```release-note
Custom resources can be listed with a set of grouped resources (category) by specifying the categories in the CustomResourceDefinition spec. Example: They can be used with `kubectl get all`, where `all` is a category.
```
/cc sttts liggitt deads2k
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kms: rename KMSService to KeyManagementService
KMSService is redundant. Introduced in #55684
@kubernetes/sig-auth-api-reviews
```release-note
NONE
```
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Refactor service storage to remove registry wrapper
This exposes the correct table exporter to the API endpoint, which is a prereq for server side GET to beta. Removing the use of the registry simplifies a few complex changes but results in test abstractions changing.
Part of #58536
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Update reclaim policy documentation
**What this PR does / why we need it**:
Documentation is out of date and doesn't mention `Delete` policy. Also `Recycle` is deprecated.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixeskubernetes/website#7469
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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Split self-signed cert and CA
The key usage limitation of TLS Server Auth makes the cert invalid as a CA.
This switches to generate a single-use CA, uses it to sign the serving cert, then appends the CA to the cert bytes.
* allows a client to continue to reference the cert file as a trust bundle, which now contains a valid CA cert
* continues to keep the generated certificate valid only for serving purposes
Fixes https://github.com/kubernetes/client-go/issues/311
```release-note
NONE
```
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Add external metric type to HPA API
**What this PR does / why we need it**:
Add external metric type to HPA API proposed in xref https://github.com/kubernetes/community/pull/1801
**Release note**:
```release-note
Allows HorizontalPodAutoscaler to use global metrics not associated with any Kubernetes object (for example metrics from a hoster service running outside of Kubernetes cluster).
```
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Make CSI volume attributes first class
**What this PR does / why we need it**:
Move CSI volume attributes from PV annotation to CSI volume source first class field
**Release note**:
```release-note
NONE
```
The registry abstraction is unnecessary and adds direct coupling to the
core types. By using a wrapper, we carry through the default
implementations of the non-mutating operations. The DeleteCollection
method is explicitly patched out since it cannot be correctly
implemented on the storage currently.
As a result, TableConvertor is now exposed.
A few other minor refactorings
* Corrected the case of some variables
* Used functions instead of methods for several helper methods
* Removed the legacy Deleter - service was the only remaining consumer
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apiextensions: add subresources for custom resources
Fixes#38113Fixes#58778
**Related**:
- Proposal: https://github.com/kubernetes/community/pull/913
- For custom resources to work with `kubectl scale`: https://github.com/kubernetes/kubernetes/pull/58283
**Add types**:
- Add `CustomResourceSubResources` type to CRD.
- Fix proto generation for `CustomResourceSubResourceStatus`: https://github.com/kubernetes/kubernetes/pull/55970.
- Add feature gate for `CustomResourceSubResources`.
- Update CRD strategy: if feature gate is disabled, this feature is dropped (i.e. set to `nil`).
- Add validation for `CustomResourceSubResources`:
- `SpecReplicasPath` should not be empty and should be a valid json path under `.spec`. If there is no value under the given path in the CustomResource, the `/scale` subresource will return an error on GET.
- `StatusReplicasPath` should not be empty and should be a valid json path under `.status`. If there is no value under the given path in the CustomResource, the status replica value in the /scale subresource will default to 0.
- If present, `LabelSelectorPath` should be a valid json path. If there is no value under `LabelSelectorPath` in the CustomResource, the status label selector value in the `/scale` subresource will default to the empty string.
- `ScaleGroupVersion` should be `autoscaling/v1`.
- If `CustomResourceSubResources` is enabled, only `properties` is allowed under the root schema for CRD validation.
**Add status and scale subresources**:
- Use helper functions from `apimachinery/pkg/apis/meta/v1/unstructured/helpers.go`.
- Improve error handling: https://github.com/kubernetes/kubernetes/pull/56563, https://github.com/kubernetes/kubernetes/pull/58215.
- Introduce Registry interface for storage.
- Update storage:
- Introduce `CustomResourceStorage` which acts as storage for the custom resource and its status and scale subresources. Note: storage for status and scale is only enabled when the feature gate is enabled _and_ the respective fields are enabled in the CRD.
- Introduce `StatusREST` and its `New()`, `Get()` and `Update()` methods.
- Introduce `ScaleREST` and its `New()`, `Get()` and `Update()` methods.
- Get and Update use the json paths from the CRD and use it to return an `autoscaling/v1.Scale` object.
- Update strategy:
- In `PrepareForCreate`,
- Clear `.status`.
- Set `.metadata.generation` = 1
- In `PrepareForUpdate`,
- Do not update `.status`.
- If both the old and new objects have `.status` and it is changed, set it back to its old value.
- If the old object has a `.status` but the new object doesn't, set it to the old value.
- If old object did not have a `.status` but the new object does, delete it.
- Increment generation if spec changes i.e. in the following cases:
- If both the old and new objects had `.spec` and it changed.
- If the old object did not have `.spec` but the new object does.
- If the old object had a `.spec` but the new object doesn't.
- In `Validate` and `ValidateUpdate`,
- ensure that values at `specReplicasPath` and `statusReplicasPath` are >=0 and < maxInt32.
- make sure there are no errors in getting the value at all the paths.
- Introduce `statusStrategy` with its methods.
- In `PrepareForUpdate`:
- Do not update `.spec`.
- If both the old and new objects have `.spec` and it is changed, set it back to its old value.
- If the old object has a `.spec` but the new object doesn't, set it to the old value.
- If old object did not have a `.spec` but the new object does, delete it.
- Do not update `.metadata`.
- In `ValidateStatusUpdate`:
- For CRD validation, validate only under `.status`.
- Validate value at `statusReplicasPath` as above. If `labelSelectorPath` is a path under `.status`, then validate it as well.
- Plug into the custom resource handler:
- Store all three storage - customResource, status and scale in `crdInfo`.
- Use the storage as per the subresource in the request.
- Use the validator as per the subresource (for status, only use the schema for `status`, if present).
- Serve the endpoint as per the subresource - see `serveResource`, `serveStatus` and `serveScale`.
- Update discovery by adding the `/status` and `/scale` resources, if enabled.
**Add tests**:
- Add unit tests in `etcd_test.go`.
- Add integration tests.
- In `subresources_test.go`, use the [polymporphic scale client](https://github.com/kubernetes/kubernetes/tree/master/staging/src/k8s.io/client-go/scale) to get and update `Scale`.
- Add a test to check everything works fine with yaml in `yaml_test.go`.
**Release note**:
```release-note
`/status` and `/scale` subresources are added for custom resources.
```
Shyam Jeedigunta