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).
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).
Fixes#60042
Seperate loop and plugin control in the kube-controller-manager.
Adding an "--external-plugin" flag to specify a plugin to load when
cloud-provider is set to "external". Flag has no effect currently
when the cloud-provider is not set to external. The expectation is
that the cloud provider and external plugin flags would go away once
all cloud providers are on stage 2 cloud-controller-manager solutions.
Managing the control loops more directly based on start up flags.
Addressing issue brought up by @wlan0
Switched to using the main node controller in CCM.
Changes to enable full NodeController to start in CCM.
Fix related tests.
Unifying some common code between KCM and CCM.
Fix related tests and comments.
Folded in feedback from @jhorwit2 and @wlan0
Automatic merge from submit-queue (batch tested with PRs 50289, 52106)
Honor --use-service-account-credentials in cloud-controller-manager
If --use-service-account-credentials is specified, the cloud controller manager should honor it
The distinction between the rootclientbuilder and the clientbuilder came from kube-controller-manager, which is responsible for running the very controllers that enable service accounts. That two-layer approach is not needed in the cloud-controller-manager.
```release-note
The `kube-cloud-controller-manager` flag `--service-account-private-key-file` was non-functional and is now deprecated.
The `kube-cloud-controller-manager` flag `--use-service-account-credentials` is now honored consistently, regardless of whether `--service-account-private-key-file` was specified.
```