Automatic merge from submit-queue
Split inflight requests into read-only and mutating groups
cc @smarterclayton @lavalamp @caesarxuchao
```release-note
API server have two separate limits for read-only and mutating inflight requests.
```
Automatic merge from submit-queue (batch tested with PRs 36816, 37534)
Move pkg/api/unversioned to pkg/apis/meta/v1
This moves code from using pkg/api/unversioned to pkg/apis/meta/v1 with the `metav1` local package name.
Built on top of #37532 (the first three commits related to ExportOptions)
Part of #37530
Automatic merge from submit-queue
plumb in front proxy group header
Builds on https://github.com/kubernetes/kubernetes/pull/36662 and https://github.com/kubernetes/kubernetes/pull/36774, so only the last commit is unique.
This completes the plumbing for front proxy header information and makes it possible to add just the front proxy header authenticator.
WIP because I'm going to assess it in use downstream.
Automatic merge from submit-queue
specify custom ca file to verify the keystone server
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**What this PR does / why we need it**:
Sometimes the keystone server's certificate is self-signed, mainly used for internal development, testing and etc.
For this kind of ca, we need a way to verify the keystone server.
Otherwise, below error will occur.
> x509: certificate signed by unknown authority
This patch provide a way to pass in a ca file to verify the keystone server when starting `kube-apiserver`.
**Which issue this PR fixes** : fixes#22695, #24984
**Special notes for your reviewer**:
**Release note**:
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``` release-note
```
Automatic merge from submit-queue
options, kube-apiserver: clarify scheme on etcd endpoints
**What this PR does / why we need it**:
Fix typo in `kube-apiserver` flag.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
None
Automatic merge from submit-queue
promote /healthz and /metrics to genericapiserver
Promotes `/healthz` to genericapiserver with methods to add healthz checks before running.
Promotes `/metrics` to genericapiserver gated by config flag.
@lavalamp adds the healthz checks linked to `postStartHooks` as promised.
Automatic merge from submit-queue
remove non-reuseable bits of MasterServer
Scrub `master.go` again. I think I'm pretty happy with this shape. I may promote `InstallAPIs` since we're likely to want it downstream.
