**What this PR does / why we need it**:
The sample-controller makes extensive use of various mechanisms
available in the client-go library. For writing custom controllers/operators
it will be helpful if there is precise description of how the
client-go library works and how/where it interfaces with
custom controller code.
This patch adds documentation that sheds light on how (parts) of the
client-go library work and its interaction-points with
controller code. The documentation and the diagram comes from [1],
(link included here for reference purpose).
[1] https://medium.com/@cloudark/kubernetes-custom-controllers-b6c7d0668fdf
Contributing the diagram and the writeup was recommended by
by @sttts and @nikhita on https://github.com/kubernetes/sample-controller/issues/13
**Release note**:
```release-note
NONE
```
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finish new dynamic client and deprecate old dynamic client
Builds on a couple other pulls. This completes the transition to the new dynamic client.
@kubernetes/sig-api-machinery-pr-reviews
@caesarxuchao @sttts
```release-note
The old dynamic client has been replaced by a new one. The previous dynamic client will exist for one release in `client-go/deprecated-dynamic`. Switch as soon as possible.
```
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CRD Status subresource support get+update+patch
CRD Status previously only supports PUT and returns 405 on GET and PATCH
/assign @sttts
/sig api-machinery
**Release note**:
```release-note
CustomResourceDefinitions Status subresource now supports GET and PATCH
```
Currently it is only possible to have one group of checks which must all pass for the handler to report success.
Allowing multiple paths for these checks allows use of the same machinery for other kinds of checks, i.e. readiness.
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sample-apiserver admission wait for informer sync before serving
**What this PR does / why we need it**:
sample-apiserver admission wait for informer sync before serving
**Release note**:
```release-note
NONE
```
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fix typo in apiextentions apiserver
the comment should be apiextentions apiserver
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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add checks validation MinRequestTimeout of ServerRunOptions
**What this PR does / why we need it**:
add checks validation MinRequestTimeout of ServerRunOptions
**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**:
I think we should check MinRequestTimeout > 0 (like RequestTimeout), in Validate() of ServerRunOptions. If it is not necessary, close this PR.Thanks
**Release note**:
```release-note
NONE
```
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fix annotation of APIGroupInfo
**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
```
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should use time.Since instead of time.Now().Sub
**What this PR does / why we need it**:
should use time.Since instead of time.Now().Sub
**Special notes for your reviewer**:
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Correct the returned message
Line 73 and line 103:
return fmt.Errorf("expected ResponseBody to be nil, got non-nill '%s'", events[i].ResponseObject.Raw)
"non-nill" should be changed to "non-nil"
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construct resource.Builder from kubeconfig flags
updates the resource.Builder to be constructed from the kubeconfig flags struct/interface that we now have.
@kubernetes/sig-cli-maintainers
@juanvallejo @soltysh
```release-note
NONE
```
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read openstack auth config from client config
**What this PR does / why we need it**:
> // TODO: read/persist client configuration(OS_XXX env vars) in config
/sig openstack
**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**:
/assign @dims
**Release note**:
```release-note
read openstack auth config from client config
```
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Stop() for Ticker to enable leak-free code
**What this PR does / why we need it**:
I wanted to use the clock package but the `Ticker` without a `Stop()` method is a deal breaker for me.
**Release note**:
```release-note
NONE
```
/kind enhancement
/sig api-machinery
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explicit kubelet config key in Node.Spec.ConfigSource.ConfigMap
This makes the Kubelet config key in the ConfigMap an explicit part of
the API, so we can stop using magic key names.
As part of this change, we are retiring ConfigMapRef for ConfigMap.
```release-note
You must now specify Node.Spec.ConfigSource.ConfigMap.KubeletConfigKey when using dynamic Kubelet config to tell the Kubelet which key of the ConfigMap identifies its config file.
```
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Fix typo in envelope transform error message
genvelope -> envelope
```release-note
NONE
```
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category expansion can only come from the server
A couple release ago we moved category expansion to the server instead of hardcoding it in the client. Similar to restmappings, there is no valid client-side expansion anymore, so this removes the code that hardcoded the list and moves the category expansion to the same package as our discovery based restmappers.
@kubernetes/sig-cli-maintainers
```release-note
NONE
```
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Exclude keys containing empty patches in the final patch
**What this PR does / why we need it**:
This minimizes the 3-way JSON merge patch generated when calculating the patch necessary to send to the server. It does this by removing empty maps created from deleting keys in the keepOrDeleteNullInObj method.
This is not only a slight performance improvement (less PATCH requests) but also necessary when working with custom resources that have RBAC restrictions.
**Which issue(s) this PR fixes**: N/A
**Special notes for your reviewer**: N/A
**Release note**:
```release-note
NONE
```
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Run resource discovery in parallel
best viewed ignoring whitespace (https://github.com/kubernetes/kubernetes/pull/63502/files?w=1)
on high-latency connections, serializing resource discovery requests across group versions can take significant amounts of time. this parallelizes the network request portion of the discovery call
xref #63368
```release-note
NONE
```
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apiextensions: allow "required" at root with status subresource
In the subresources alpha we intentionally disallowed anything than `properties` at the root of the validation schema in order to allow us to project it to the .status subtree. By doing this we also disallowed `required` at the root which is necessary to enforce e.g. a spec to be set. This PR fixes this.
Moreover, it fixes that the restriction is only enforced when the status subresource is actually enabled. Before this PR we were enforcing the restriction as soon as the feature gate was enabled, leading to a backwards incompatible change.
```release-note
Allow "required" to be used at the CRD OpenAPI validation schema when the /status subresource is enabled.
```
There was an issue reporting the bug. But cannot find it.
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[CustomResourceSubresources] fix status subresource
This change make the codes consistent with the document.
Fixes: https://github.com/kubernetes/kubernetes/issues/63359
**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**:
/assign @nikhita
**Release note**:
```release-note
When updating /status subresource of a custom resource, only the value at the `.status` subpath for the update is considered.
```
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Return error when has no RequestInfo in handlerchain
**What this PR does / why we need it**:
we should return error when has no RequestInfo.
**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
```
This makes the Kubelet config key in the ConfigMap an explicit part of
the API, so we can stop using magic key names.
As part of this change, we are retiring ConfigMapRef for ConfigMap.
