generic-controlplane: add generic-controlplane apiserver sample

Signed-off-by: Dr. Stefan Schimanski <stefan.schimanski@gmail.com>

generic

Signed-off-by: Dr. Stefan Schimanski <stefan.schimanski@gmail.com>

pkg/controlplane/apiserver/samples/doc.go

@@ -0,0 +1,23 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package samples contains two kube-like generic control plane apiserver, one
+// with CRDs (generic) and one without (minimum).
+//
+// They are here mainly to preserve the feasibility to construct these kind of
+// control planes. Eventually, we might promote them to be example for 3rd parties
+// to follow.
+package samples

pkg/controlplane/apiserver/samples/generic/OWNERS

@@ -0,0 +1,13 @@
+# See the OWNERS docs at https://go.k8s.io/owners
+
+approvers:
+  - sttts
+  - deads2k
+  - jpbetz
+reviewers:
+  - sttts
+  - deads2k
+  - jpbetz
+labels:
+  - sig/api-machinery
+  - area/apiserver

pkg/controlplane/apiserver/samples/generic/doc.go

@@ -0,0 +1,22 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// sample-generic-controlplane is a kube-like generic control plane
+// - with CRDs
+// - with generic Kube native APIs
+// - with aggregation
+// - without the container domain specific APIs.
+package main

pkg/controlplane/apiserver/samples/generic/main.go

@@ -0,0 +1,36 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// sample-generic-controlplane is a kube-like generic control plane
+// It is compatible to kube-apiserver, but lacks the container domain
+// specific APIs.
+package main
+
+import (
+	"os"
+
+	"k8s.io/component-base/cli"
+	_ "k8s.io/component-base/logs/json/register"
+	_ "k8s.io/component-base/metrics/prometheus/clientgo"
+	_ "k8s.io/component-base/metrics/prometheus/version"
+	"k8s.io/kubernetes/pkg/controlplane/apiserver/samples/generic/server"
+)
+
+func main() {
+	command := server.NewCommand()
+	code := cli.Run(command)
+	os.Exit(code)
+}

pkg/controlplane/apiserver/samples/generic/server/admission.go

@@ -0,0 +1,52 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package server
+
+import (
+	"k8s.io/apimachinery/pkg/util/sets"
+	"k8s.io/apiserver/pkg/admission/plugin/namespace/lifecycle"
+	validatingadmissionpolicy "k8s.io/apiserver/pkg/admission/plugin/policy/validating"
+	"k8s.io/apiserver/pkg/admission/plugin/resourcequota"
+	mutatingwebhook "k8s.io/apiserver/pkg/admission/plugin/webhook/mutating"
+	validatingwebhook "k8s.io/apiserver/pkg/admission/plugin/webhook/validating"
+	"k8s.io/kubernetes/pkg/kubeapiserver/options"
+	certapproval "k8s.io/kubernetes/plugin/pkg/admission/certificates/approval"
+	"k8s.io/kubernetes/plugin/pkg/admission/certificates/ctbattest"
+	certsigning "k8s.io/kubernetes/plugin/pkg/admission/certificates/signing"
+	certsubjectrestriction "k8s.io/kubernetes/plugin/pkg/admission/certificates/subjectrestriction"
+	"k8s.io/kubernetes/plugin/pkg/admission/defaulttolerationseconds"
+	"k8s.io/kubernetes/plugin/pkg/admission/serviceaccount"
+)
+
+// DefaultOffAdmissionPlugins get admission plugins off by default for kube-apiserver.
+func DefaultOffAdmissionPlugins() sets.Set[string] {
+	defaultOnPlugins := sets.New[string](
+		lifecycle.PluginName,                 // NamespaceLifecycle
+		serviceaccount.PluginName,            // ServiceAccount
+		defaulttolerationseconds.PluginName,  // DefaultTolerationSeconds
+		mutatingwebhook.PluginName,           // MutatingAdmissionWebhook
+		validatingwebhook.PluginName,         // ValidatingAdmissionWebhook
+		resourcequota.PluginName,             // ResourceQuota
+		certapproval.PluginName,              // CertificateApproval
+		certsigning.PluginName,               // CertificateSigning
+		ctbattest.PluginName,                 // ClusterTrustBundleAttest
+		certsubjectrestriction.PluginName,    // CertificateSubjectRestriction
+		validatingadmissionpolicy.PluginName, // ValidatingAdmissionPolicy, only active when feature gate ValidatingAdmissionPolicy is enabled
+	)
+
+	return sets.New(options.AllOrderedPlugins...).Difference(defaultOnPlugins)
+}

pkg/controlplane/apiserver/samples/generic/server/admission_test.go

@@ -0,0 +1,55 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package server
+
+import (
+	"testing"
+
+	"k8s.io/apimachinery/pkg/util/sets"
+	kubeoptions "k8s.io/kubernetes/pkg/kubeapiserver/options"
+	"k8s.io/kubernetes/plugin/pkg/admission/limitranger"
+	"k8s.io/kubernetes/plugin/pkg/admission/network/defaultingressclass"
+	"k8s.io/kubernetes/plugin/pkg/admission/nodetaint"
+	podpriority "k8s.io/kubernetes/plugin/pkg/admission/priority"
+	"k8s.io/kubernetes/plugin/pkg/admission/runtimeclass"
+	"k8s.io/kubernetes/plugin/pkg/admission/security/podsecurity"
+	"k8s.io/kubernetes/plugin/pkg/admission/storage/persistentvolume/resize"
+	"k8s.io/kubernetes/plugin/pkg/admission/storage/storageclass/setdefault"
+	"k8s.io/kubernetes/plugin/pkg/admission/storage/storageobjectinuseprotection"
+)
+
+var intentionallyOffPlugins = sets.New[string](
+	limitranger.PluginName,                  // LimitRanger
+	setdefault.PluginName,                   // DefaultStorageClass
+	resize.PluginName,                       // PersistentVolumeClaimResize
+	storageobjectinuseprotection.PluginName, // StorageObjectInUseProtection
+	podpriority.PluginName,                  // Priority
+	nodetaint.PluginName,                    // TaintNodesByCondition
+	runtimeclass.PluginName,                 // RuntimeClass
+	defaultingressclass.PluginName,          // DefaultIngressClass
+	podsecurity.PluginName,                  // PodSecurity
+)
+
+func TestDefaultOffAdmissionPlugins(t *testing.T) {
+	expectedOff := kubeoptions.DefaultOffAdmissionPlugins().Union(intentionallyOffPlugins)
+	if missing := DefaultOffAdmissionPlugins().Difference(expectedOff); missing.Len() > 0 {
+		t.Fatalf("generic DefaultOffAdmissionPlugins() is incomplete, double check: %v", missing)
+	}
+	if unexpected := expectedOff.Difference(DefaultOffAdmissionPlugins()); unexpected.Len() > 0 {
+		t.Fatalf("generic DefaultOffAdmissionPlugins() has unepxeced plugins, double check: %v", unexpected)
+	}
+}

pkg/controlplane/apiserver/samples/generic/server/config.go

@@ -0,0 +1,112 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package server
+
+import (
+	apiextensionsapiserver "k8s.io/apiextensions-apiserver/pkg/apiserver"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apiserver/pkg/util/webhook"
+	aggregatorapiserver "k8s.io/kube-aggregator/pkg/apiserver"
+	aggregatorscheme "k8s.io/kube-aggregator/pkg/apiserver/scheme"
+	"k8s.io/kubernetes/pkg/controlplane"
+
+	"k8s.io/kubernetes/pkg/api/legacyscheme"
+	controlplaneapiserver "k8s.io/kubernetes/pkg/controlplane/apiserver"
+	"k8s.io/kubernetes/pkg/controlplane/apiserver/options"
+	generatedopenapi "k8s.io/kubernetes/pkg/generated/openapi"
+)
+
+type Config struct {
+	Options options.CompletedOptions
+
+	Aggregator    *aggregatorapiserver.Config
+	ControlPlane  *controlplaneapiserver.Config
+	APIExtensions *apiextensionsapiserver.Config
+
+	ExtraConfig
+}
+
+type ExtraConfig struct {
+}
+
+type completedConfig struct {
+	Options options.CompletedOptions
+
+	Aggregator    aggregatorapiserver.CompletedConfig
+	ControlPlane  controlplaneapiserver.CompletedConfig
+	APIExtensions apiextensionsapiserver.CompletedConfig
+
+	ExtraConfig
+}
+
+type CompletedConfig struct {
+	// Embed a private pointer that cannot be instantiated outside of this package.
+	*completedConfig
+}
+
+func (c *Config) Complete() (CompletedConfig, error) {
+	return CompletedConfig{&completedConfig{
+		Options: c.Options,
+
+		Aggregator:    c.Aggregator.Complete(),
+		ControlPlane:  c.ControlPlane.Complete(),
+		APIExtensions: c.APIExtensions.Complete(),
+
+		ExtraConfig: c.ExtraConfig,
+	}}, nil
+}
+
+// NewConfig creates all the self-contained pieces making up an
+// sample-generic-controlplane, but does not wire them yet into a server object.
+func NewConfig(opts options.CompletedOptions) (*Config, error) {
+	c := &Config{
+		Options: opts,
+	}
+
+	genericConfig, versionedInformers, storageFactory, err := controlplaneapiserver.BuildGenericConfig(
+		opts,
+		[]*runtime.Scheme{legacyscheme.Scheme, apiextensionsapiserver.Scheme, aggregatorscheme.Scheme},
+		controlplane.DefaultAPIResourceConfigSource(),
+		generatedopenapi.GetOpenAPIDefinitions,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	serviceResolver := webhook.NewDefaultServiceResolver()
+	kubeAPIs, pluginInitializer, err := controlplaneapiserver.CreateConfig(opts, genericConfig, versionedInformers, storageFactory, serviceResolver, nil)
+	if err != nil {
+		return nil, err
+	}
+	c.ControlPlane = kubeAPIs
+
+	authInfoResolver := webhook.NewDefaultAuthenticationInfoResolverWrapper(kubeAPIs.ProxyTransport, kubeAPIs.Generic.EgressSelector, kubeAPIs.Generic.LoopbackClientConfig, kubeAPIs.Generic.TracerProvider)
+	apiExtensions, err := controlplaneapiserver.CreateAPIExtensionsConfig(*kubeAPIs.Generic, kubeAPIs.VersionedInformers, pluginInitializer, opts, 3, serviceResolver, authInfoResolver)
+	if err != nil {
+		return nil, err
+	}
+	c.APIExtensions = apiExtensions
+
+	aggregator, err := controlplaneapiserver.CreateAggregatorConfig(*kubeAPIs.Generic, opts, kubeAPIs.VersionedInformers, serviceResolver, kubeAPIs.ProxyTransport, kubeAPIs.Extra.PeerProxy, pluginInitializer)
+	if err != nil {
+		return nil, err
+	}
+	c.Aggregator = aggregator
+	c.Aggregator.ExtraConfig.DisableRemoteAvailableConditionController = true
+
+	return c, nil
+}

pkg/controlplane/apiserver/samples/generic/server/server.go

@@ -0,0 +1,202 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package server
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/cobra"
+	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
+	utilerrors "k8s.io/apimachinery/pkg/util/errors"
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	_ "k8s.io/apiserver/pkg/admission"
+	genericapifilters "k8s.io/apiserver/pkg/endpoints/filters"
+	genericapiserver "k8s.io/apiserver/pkg/server"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
+	"k8s.io/apiserver/pkg/util/notfoundhandler"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+	cliflag "k8s.io/component-base/cli/flag"
+	"k8s.io/component-base/cli/globalflag"
+	"k8s.io/component-base/logs"
+	logsapi "k8s.io/component-base/logs/api/v1"
+	_ "k8s.io/component-base/metrics/prometheus/workqueue"
+	"k8s.io/component-base/term"
+	"k8s.io/component-base/version"
+	"k8s.io/component-base/version/verflag"
+	"k8s.io/klog/v2"
+	aggregatorapiserver "k8s.io/kube-aggregator/pkg/apiserver"
+
+	controlplaneapiserver "k8s.io/kubernetes/pkg/controlplane/apiserver"
+	"k8s.io/kubernetes/pkg/controlplane/apiserver/options"
+	_ "k8s.io/kubernetes/pkg/features"
+	// add the kubernetes feature gates
+)
+
+func init() {
+	utilruntime.Must(logsapi.AddFeatureGates(utilfeature.DefaultMutableFeatureGate))
+}
+
+// NewCommand creates a *cobra.Command object with default parameters
+func NewCommand() *cobra.Command {
+	s := NewOptions()
+	cmd := &cobra.Command{
+		Use: "sample-generic-apiserver",
+		Long: `The sample generic apiserver is part of a generic controlplane,
+a system serving APIs like Kubernetes, but without the container domain specific
+APIs.`,
+
+		// stop printing usage when the command errors
+		SilenceUsage: true,
+		PersistentPreRunE: func(*cobra.Command, []string) error {
+			// silence client-go warnings.
+			// kube-apiserver loopback clients should not log self-issued warnings.
+			rest.SetDefaultWarningHandler(rest.NoWarnings{})
+			return nil
+		},
+		RunE: func(cmd *cobra.Command, args []string) error {
+			verflag.PrintAndExitIfRequested()
+			fs := cmd.Flags()
+
+			// Activate logging as soon as possible, after that
+			// show flags with the final logging configuration.
+			if err := logsapi.ValidateAndApply(s.Logs, utilfeature.DefaultFeatureGate); err != nil {
+				return err
+			}
+			cliflag.PrintFlags(fs)
+
+			completedOptions, err := s.Complete([]string{}, []net.IP{})
+			if err != nil {
+				return err
+			}
+
+			if errs := completedOptions.Validate(); len(errs) != 0 {
+				return utilerrors.NewAggregate(errs)
+			}
+
+			// add feature enablement metrics
+			utilfeature.DefaultMutableFeatureGate.AddMetrics()
+			ctx := genericapiserver.SetupSignalContext()
+			return Run(ctx, completedOptions)
+		},
+		Args: func(cmd *cobra.Command, args []string) error {
+			for _, arg := range args {
+				if len(arg) > 0 {
+					return fmt.Errorf("%q does not take any arguments, got %q", cmd.CommandPath(), args)
+				}
+			}
+			return nil
+		},
+	}
+
+	var namedFlagSets cliflag.NamedFlagSets
+	s.AddFlags(&namedFlagSets)
+	verflag.AddFlags(namedFlagSets.FlagSet("global"))
+	globalflag.AddGlobalFlags(namedFlagSets.FlagSet("global"), cmd.Name(), logs.SkipLoggingConfigurationFlags())
+
+	fs := cmd.Flags()
+	for _, f := range namedFlagSets.FlagSets {
+		fs.AddFlagSet(f)
+	}
+
+	cols, _, _ := term.TerminalSize(cmd.OutOrStdout())
+	cliflag.SetUsageAndHelpFunc(cmd, namedFlagSets, cols)
+
+	return cmd
+}
+
+func NewOptions() *options.Options {
+	s := options.NewOptions()
+	s.Admission.GenericAdmission.DefaultOffPlugins = DefaultOffAdmissionPlugins()
+
+	wd, _ := os.Getwd()
+	s.SecureServing.ServerCert.CertDirectory = filepath.Join(wd, ".sample-minimal-controlplane")
+
+	// Wire ServiceAccount authentication without relying on pods and nodes.
+	s.Authentication.ServiceAccounts.OptionalTokenGetter = genericTokenGetter
+
+	return s
+}
+
+// Run runs the specified APIServer. This should never exit.
+func Run(ctx context.Context, opts options.CompletedOptions) error {
+	// To help debugging, immediately log version
+	klog.Infof("Version: %+v", version.Get())
+
+	klog.InfoS("Golang settings", "GOGC", os.Getenv("GOGC"), "GOMAXPROCS", os.Getenv("GOMAXPROCS"), "GOTRACEBACK", os.Getenv("GOTRACEBACK"))
+
+	config, err := NewConfig(opts)
+	if err != nil {
+		return err
+	}
+	completed, err := config.Complete()
+	if err != nil {
+		return err
+	}
+	server, err := CreateServerChain(completed)
+	if err != nil {
+		return err
+	}
+
+	prepared, err := server.PrepareRun()
+	if err != nil {
+		return err
+	}
+
+	return prepared.Run(ctx)
+}
+
+// CreateServerChain creates the apiservers connected via delegation.
+func CreateServerChain(config CompletedConfig) (*aggregatorapiserver.APIAggregator, error) {
+	// 1. CRDs
+	notFoundHandler := notfoundhandler.New(config.ControlPlane.Generic.Serializer, genericapifilters.NoMuxAndDiscoveryIncompleteKey)
+	apiExtensionsServer, err := config.APIExtensions.New(genericapiserver.NewEmptyDelegateWithCustomHandler(notFoundHandler))
+	if err != nil {
+		return nil, fmt.Errorf("failed to create apiextensions-apiserver: %w", err)
+	}
+	crdAPIEnabled := config.APIExtensions.GenericConfig.MergedResourceConfig.ResourceEnabled(apiextensionsv1.SchemeGroupVersion.WithResource("customresourcedefinitions"))
+
+	// 2. Natively implemented resources
+	nativeAPIs, err := config.ControlPlane.New("sample-generic-controlplane", apiExtensionsServer.GenericAPIServer)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create generic controlplane apiserver: %w", err)
+	}
+	client, err := kubernetes.NewForConfig(config.ControlPlane.Generic.LoopbackClientConfig)
+	if err != nil {
+		return nil, err
+	}
+	storageProviders, err := config.ControlPlane.GenericStorageProviders(client.Discovery())
+	if err != nil {
+		return nil, fmt.Errorf("failed to create storage providers: %w", err)
+	}
+	if err := nativeAPIs.InstallAPIs(storageProviders...); err != nil {
+		return nil, fmt.Errorf("failed to install APIs: %w", err)
+	}
+
+	// 3. Aggregator for APIServices, discovery and OpenAPI
+	aggregatorServer, err := controlplaneapiserver.CreateAggregatorServer(config.Aggregator, nativeAPIs.GenericAPIServer, apiExtensionsServer.Informers.Apiextensions().V1().CustomResourceDefinitions(), crdAPIEnabled, controlplaneapiserver.DefaultGenericAPIServicePriorities())
+	if err != nil {
+		// we don't need special handling for innerStopCh because the aggregator server doesn't create any go routines
+		return nil, fmt.Errorf("failed to create kube-aggregator: %w", err)
+	}
+
+	return aggregatorServer, nil
+}

pkg/controlplane/apiserver/samples/generic/server/serviceaccounts.go

@@ -0,0 +1,53 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package server
+
+import (
+	v1 "k8s.io/api/core/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/client-go/informers"
+	v1listers "k8s.io/client-go/listers/core/v1"
+	"k8s.io/kubernetes/pkg/serviceaccount"
+)
+
+// clientGetter implements ServiceAccountTokenGetter using a factory function
+type clientGetter struct {
+	secretLister         v1listers.SecretLister
+	serviceAccountLister v1listers.ServiceAccountLister
+}
+
+// genericTokenGetter returns a ServiceAccountTokenGetter that does not depend
+// on pods and nodes.
+func genericTokenGetter(factory informers.SharedInformerFactory) serviceaccount.ServiceAccountTokenGetter {
+	return clientGetter{secretLister: factory.Core().V1().Secrets().Lister(), serviceAccountLister: factory.Core().V1().ServiceAccounts().Lister()}
+}
+
+func (c clientGetter) GetServiceAccount(namespace, name string) (*v1.ServiceAccount, error) {
+	return c.serviceAccountLister.ServiceAccounts(namespace).Get(name)
+}
+
+func (c clientGetter) GetPod(namespace, name string) (*v1.Pod, error) {
+	return nil, apierrors.NewNotFound(v1.Resource("pods"), name)
+}
+
+func (c clientGetter) GetSecret(namespace, name string) (*v1.Secret, error) {
+	return c.secretLister.Secrets(namespace).Get(name)
+}
+
+func (c clientGetter) GetNode(name string) (*v1.Node, error) {
+	return nil, apierrors.NewNotFound(v1.Resource("nodes"), name)
+}

pkg/controlplane/apiserver/samples/generic/server/testing/testdata/127.0.0.1__localhost.crt

@@ -0,0 +1,39 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

pkg/controlplane/apiserver/samples/generic/server/testing/testdata/127.0.0.1__localhost.key

@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----

pkg/controlplane/apiserver/samples/generic/server/testing/testdata/README.md

@@ -0,0 +1 @@
+Keys in this directory are generated for testing purposes only.

pkg/controlplane/apiserver/samples/generic/server/testing/testserver.go

@@ -0,0 +1,348 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package testing
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"os"
+	"path/filepath"
+	"runtime"
+	"time"
+
+	"github.com/spf13/pflag"
+	"go.etcd.io/etcd/client/pkg/v3/transport"
+	clientv3 "go.etcd.io/etcd/client/v3"
+	"google.golang.org/grpc"
+	"k8s.io/kubernetes/pkg/controlplane/apiserver/samples/generic/server"
+
+	"k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	utilerrors "k8s.io/apimachinery/pkg/util/errors"
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	"k8s.io/apimachinery/pkg/util/wait"
+	"k8s.io/apiserver/pkg/storage/storagebackend"
+	"k8s.io/client-go/kubernetes"
+	restclient "k8s.io/client-go/rest"
+	cliflag "k8s.io/component-base/cli/flag"
+	logsapi "k8s.io/component-base/logs/api/v1"
+	"k8s.io/klog/v2"
+	controlplaneapiserver "k8s.io/kubernetes/pkg/controlplane/apiserver/options"
+	"k8s.io/kubernetes/test/utils/ktesting"
+)
+
+func init() {
+	// If instantiated more than once or together with other servers, the
+	// servers would try to modify the global logging state. This must get
+	// ignored during testing.
+	logsapi.ReapplyHandling = logsapi.ReapplyHandlingIgnoreUnchanged
+}
+
+// This key is for testing purposes only and is not considered secure.
+const ecdsaPrivateKey = `-----BEGIN EC PRIVATE KEY-----
+MHcCAQEEIEZmTmUhuanLjPA2CLquXivuwBDHTt5XYwgIr/kA1LtRoAoGCCqGSM49
+AwEHoUQDQgAEH6cuzP8XuD5wal6wf9M6xDljTOPLX2i8uIp/C/ASqiIGUeeKQtX0
+/IR3qCXyThP/dbCiHrF3v1cuhBOHY8CLVg==
+-----END EC PRIVATE KEY-----`
+
+// TearDownFunc is to be called to tear down a test server.
+type TearDownFunc func()
+
+// TestServerInstanceOptions Instance options the TestServer
+type TestServerInstanceOptions struct {
+	// SkipHealthzCheck returns without waiting for the server to become healthy.
+	// Useful for testing server configurations expected to prevent /healthz from completing.
+	SkipHealthzCheck bool
+}
+
+// TestServer represents a running test server with everything to access it and
+// its backing store etcd.
+type TestServer struct {
+	ClientConfig      *restclient.Config             // Rest client config
+	ServerOpts        *controlplaneapiserver.Options // ServerOpts
+	TearDownFn        TearDownFunc                   // TearDown function
+	TmpDir            string                         // Temp Dir used, by the apiserver
+	EtcdClient        *clientv3.Client               // used by tests that need to check data migrated from APIs that are no longer served
+	EtcdStoragePrefix string                         // storage prefix in etcd
+}
+
+// NewDefaultTestServerOptions default options for TestServer instances
+func NewDefaultTestServerOptions() *TestServerInstanceOptions {
+	return &TestServerInstanceOptions{}
+}
+
+// StartTestServer starts an etcd server and sample-generic-controlplane and
+// returns a TestServer struct with a tear-down func and clients to access it
+// and its backing store.
+func StartTestServer(t ktesting.TB, instanceOptions *TestServerInstanceOptions, customFlags []string, storageConfig *storagebackend.Config) (result TestServer, err error) {
+	tCtx := ktesting.Init(t)
+
+	if instanceOptions == nil {
+		instanceOptions = NewDefaultTestServerOptions()
+	}
+
+	result.TmpDir, err = os.MkdirTemp("", "sample-generic-controlplane")
+	if err != nil {
+		return result, fmt.Errorf("failed to create temp dir: %w", err)
+	}
+
+	var errCh chan error
+	tearDown := func() {
+		// Cancel is stopping apiserver and cleaning up
+		// after itself, including shutting down its storage layer.
+		tCtx.Cancel("tearing down")
+
+		// If the apiserver was started, let's wait for it to
+		// shutdown clearly.
+		if errCh != nil {
+			err, ok := <-errCh
+			if ok && err != nil {
+				klog.Errorf("Failed to shutdown test server clearly: %v", err)
+			}
+		}
+		os.RemoveAll(result.TmpDir) //nolint:errcheck // best effort
+	}
+	defer func() {
+		if result.TearDownFn == nil {
+			tearDown()
+		}
+	}()
+
+	o := server.NewOptions()
+	var fss cliflag.NamedFlagSets
+	o.AddFlags(&fss)
+
+	fs := pflag.NewFlagSet("test", pflag.PanicOnError)
+	for _, f := range fss.FlagSets {
+		fs.AddFlagSet(f)
+	}
+
+	o.SecureServing.Listener, o.SecureServing.BindPort, err = createLocalhostListenerOnFreePort()
+	if err != nil {
+		return result, fmt.Errorf("failed to create listener: %w", err)
+	}
+	o.SecureServing.ServerCert.CertDirectory = result.TmpDir
+	o.SecureServing.ExternalAddress = o.SecureServing.Listener.Addr().(*net.TCPAddr).IP // use listener addr although it is a loopback device
+
+	pkgPath, err := pkgPath(t)
+	if err != nil {
+		return result, err
+	}
+	o.SecureServing.ServerCert.FixtureDirectory = filepath.Join(pkgPath, "testdata")
+
+	o.Etcd.StorageConfig = *storageConfig
+	utilruntime.Must(o.APIEnablement.RuntimeConfig.Set("api/all=true"))
+
+	if err := fs.Parse(customFlags); err != nil {
+		return result, err
+	}
+
+	saSigningKeyFile, err := os.CreateTemp("/tmp", "insecure_test_key")
+	if err != nil {
+		t.Fatalf("create temp file failed: %v", err)
+	}
+	defer os.RemoveAll(saSigningKeyFile.Name()) //nolint:errcheck // best effort
+	if err = os.WriteFile(saSigningKeyFile.Name(), []byte(ecdsaPrivateKey), 0666); err != nil {
+		t.Fatalf("write file %s failed: %v", saSigningKeyFile.Name(), err)
+	}
+	o.ServiceAccountSigningKeyFile = saSigningKeyFile.Name()
+	o.Authentication.ServiceAccounts.Issuers = []string{"https://foo.bar.example.com"}
+	o.Authentication.ServiceAccounts.KeyFiles = []string{saSigningKeyFile.Name()}
+
+	completedOptions, err := o.Complete(nil, nil)
+	if err != nil {
+		return result, fmt.Errorf("failed to set default ServerRunOptions: %w", err)
+	}
+
+	if errs := completedOptions.Validate(); len(errs) != 0 {
+		return result, fmt.Errorf("failed to validate ServerRunOptions: %w", utilerrors.NewAggregate(errs))
+	}
+
+	t.Logf("runtime-config=%v", completedOptions.APIEnablement.RuntimeConfig)
+	t.Logf("Starting sample-generic-controlplane on port %d...", o.SecureServing.BindPort)
+
+	config, err := server.NewConfig(completedOptions)
+	if err != nil {
+		return result, err
+	}
+	completed, err := config.Complete()
+	if err != nil {
+		return result, err
+	}
+	s, err := server.CreateServerChain(completed)
+	if err != nil {
+		return result, fmt.Errorf("failed to create server chain: %w", err)
+	}
+
+	errCh = make(chan error)
+	go func() {
+		defer close(errCh)
+		prepared, err := s.PrepareRun()
+		if err != nil {
+			errCh <- err
+		} else if err := prepared.Run(tCtx); err != nil {
+			errCh <- err
+		}
+	}()
+
+	client, err := kubernetes.NewForConfig(s.GenericAPIServer.LoopbackClientConfig)
+	if err != nil {
+		return result, fmt.Errorf("failed to create a client: %w", err)
+	}
+
+	if !instanceOptions.SkipHealthzCheck {
+		t.Logf("Waiting for /healthz to be ok...")
+
+		// wait until healthz endpoint returns ok
+		err = wait.PollUntilContextTimeout(tCtx, 100*time.Millisecond, wait.ForeverTestTimeout, true, func(ctx context.Context) (bool, error) {
+			select {
+			case err := <-errCh:
+				return false, err
+			default:
+			}
+
+			req := client.CoreV1().RESTClient().Get().AbsPath("/healthz")
+			result := req.Do(ctx)
+			status := 0
+			result.StatusCode(&status)
+			if status == 200 {
+				return true, nil
+			}
+			return false, nil
+		})
+		if err != nil {
+			return result, fmt.Errorf("failed to wait for /healthz to return ok: %w", err)
+		}
+	}
+
+	// wait until default namespace is created
+	err = wait.PollUntilContextTimeout(tCtx, 100*time.Millisecond, wait.ForeverTestTimeout, true, func(ctx context.Context) (bool, error) {
+		select {
+		case err := <-errCh:
+			return false, err
+		default:
+		}
+
+		if _, err := client.CoreV1().Namespaces().Get(ctx, "default", metav1.GetOptions{}); err != nil {
+			if !errors.IsNotFound(err) {
+				t.Logf("Unable to get default namespace: %v", err)
+			}
+			return false, nil
+		}
+		return true, nil
+	})
+	if err != nil {
+		return result, fmt.Errorf("failed to wait for default namespace to be created: %w", err)
+	}
+
+	tlsInfo := transport.TLSInfo{
+		CertFile:      storageConfig.Transport.CertFile,
+		KeyFile:       storageConfig.Transport.KeyFile,
+		TrustedCAFile: storageConfig.Transport.TrustedCAFile,
+	}
+	tlsConfig, err := tlsInfo.ClientConfig()
+	if err != nil {
+		return result, err
+	}
+	etcdConfig := clientv3.Config{
+		Endpoints:   storageConfig.Transport.ServerList,
+		DialTimeout: 20 * time.Second,
+		DialOptions: []grpc.DialOption{
+			grpc.WithBlock(), // block until the underlying connection is up
+		},
+		TLS: tlsConfig,
+	}
+	etcdClient, err := clientv3.New(etcdConfig)
+	if err != nil {
+		return result, err
+	}
+
+	// from here the caller must call tearDown
+	result.ClientConfig = restclient.CopyConfig(s.GenericAPIServer.LoopbackClientConfig)
+	result.ClientConfig.QPS = 1000
+	result.ClientConfig.Burst = 10000
+	result.ServerOpts = o
+	result.TearDownFn = func() {
+		tearDown()
+		etcdClient.Close() //nolint:errcheck // best effort
+	}
+	result.EtcdClient = etcdClient
+	result.EtcdStoragePrefix = storageConfig.Prefix
+
+	return result, nil
+}
+
+// StartTestServerOrDie calls StartTestServer t.Fatal if it does not succeed.
+func StartTestServerOrDie(t ktesting.TB, instanceOptions *TestServerInstanceOptions, flags []string, storageConfig *storagebackend.Config) *TestServer {
+	result, err := StartTestServer(t, instanceOptions, flags, storageConfig)
+	if err == nil {
+		return &result
+	}
+
+	t.Fatalf("failed to launch server: %v", err)
+	return nil
+}
+
+func createLocalhostListenerOnFreePort() (net.Listener, int, error) {
+	ln, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		return nil, 0, err
+	}
+
+	// get port
+	tcpAddr, ok := ln.Addr().(*net.TCPAddr)
+	if !ok {
+		ln.Close() //nolint:errcheck // best effort
+		return nil, 0, fmt.Errorf("invalid listen address: %q", ln.Addr().String())
+	}
+
+	return ln, tcpAddr.Port, nil
+}
+
+// pkgPath returns the absolute file path to this package's directory. With go
+// test, we can just look at the runtime call stack. However, bazel compiles go
+// binaries with the -trimpath option so the simple approach fails however we
+// can consult environment variables to derive the path.
+//
+// The approach taken here works for both go test and bazel on the assumption
+// that if and only if trimpath is passed, we are running under bazel.
+func pkgPath(t ktesting.TB) (string, error) {
+	_, thisFile, _, ok := runtime.Caller(0)
+	if !ok {
+		return "", fmt.Errorf("failed to get current file")
+	}
+
+	pkgPath := filepath.Dir(thisFile)
+
+	// If we find bazel env variables, then -trimpath was passed so we need to
+	// construct the path from the environment.
+	if testSrcdir, testWorkspace := os.Getenv("TEST_SRCDIR"), os.Getenv("TEST_WORKSPACE"); testSrcdir != "" && testWorkspace != "" {
+		t.Logf("Detected bazel env varaiables: TEST_SRCDIR=%q TEST_WORKSPACE=%q", testSrcdir, testWorkspace)
+		pkgPath = filepath.Join(testSrcdir, testWorkspace, pkgPath)
+	}
+
+	// If the path is still not absolute, something other than bazel compiled
+	// with -trimpath.
+	if !filepath.IsAbs(pkgPath) {
+		return "", fmt.Errorf("can't construct an absolute path from %q", pkgPath)
+	}
+
+	t.Logf("Resolved testserver package path to: %q", pkgPath)
+
+	return pkgPath, nil
+}

test/integration/controlplane/generic_test.go

@@ -0,0 +1,136 @@
+/*
+Copyright 2024 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package controlplane
+
+import (
+	"context"
+	"strings"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/stretchr/testify/require"
+	corev1 "k8s.io/api/core/v1"
+	apiextensionsclientset "k8s.io/apiextensions-apiserver/pkg/client/clientset/clientset"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/util/sets"
+	"k8s.io/client-go/dynamic"
+	"k8s.io/client-go/kubernetes"
+	genericcontrolplanetesting "k8s.io/kubernetes/pkg/controlplane/apiserver/samples/generic/server/testing"
+	"k8s.io/kubernetes/test/integration/etcd"
+	"k8s.io/kubernetes/test/integration/framework"
+)
+
+func TestGenericControlplaneStartUp(t *testing.T) {
+	server, err := genericcontrolplanetesting.StartTestServer(t, genericcontrolplanetesting.NewDefaultTestServerOptions(), nil, framework.SharedEtcd())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer server.TearDownFn()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	t.Cleanup(cancel)
+
+	client, err := kubernetes.NewForConfig(server.ClientConfig)
+	if err != nil {
+		t.Fatal(err)
+	}
+	dynamicClient, err := dynamic.NewForConfig(server.ClientConfig)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = client.RESTClient().Get().AbsPath("/readyz").Do(ctx).Raw()
+	require.NoError(t, err)
+
+	groups, err := client.Discovery().ServerPreferredResources()
+	require.NoError(t, err)
+
+	t.Logf("Found %d API groups", len(groups))
+	grs := sets.New[string]()
+	for _, g := range groups {
+		var group string
+		comps := strings.SplitN(g.GroupVersion, "/", 2)
+		if len(comps) == 2 {
+			group = comps[0]
+		}
+		for _, r := range g.APIResources {
+			grs.Insert(schema.GroupResource{Group: group, Resource: r.Name}.String())
+		}
+	}
+	expected := sets.New[string](
+		"apiservices.apiregistration.k8s.io",
+		"certificatesigningrequests.certificates.k8s.io",
+		"clusterrolebindings.rbac.authorization.k8s.io",
+		"clusterroles.rbac.authorization.k8s.io",
+		"configmaps",
+		"customresourcedefinitions.apiextensions.k8s.io",
+		"events",
+		"events.events.k8s.io",
+		"flowschemas.flowcontrol.apiserver.k8s.io",
+		"leases.coordination.k8s.io",
+		"localsubjectaccessreviews.authorization.k8s.io",
+		"mutatingwebhookconfigurations.admissionregistration.k8s.io",
+		"namespaces",
+		"prioritylevelconfigurations.flowcontrol.apiserver.k8s.io",
+		"resourcequotas",
+		"rolebindings.rbac.authorization.k8s.io",
+		"roles.rbac.authorization.k8s.io",
+		"secrets",
+		"selfsubjectaccessreviews.authorization.k8s.io",
+		"selfsubjectreviews.authentication.k8s.io",
+		"selfsubjectrulesreviews.authorization.k8s.io",
+		"serviceaccounts",
+		"storageversions.internal.apiserver.k8s.io",
+		"subjectaccessreviews.authorization.k8s.io",
+		"tokenreviews.authentication.k8s.io",
+		"validatingadmissionpolicies.admissionregistration.k8s.io",
+		"validatingadmissionpolicybindings.admissionregistration.k8s.io",
+		"validatingwebhookconfigurations.admissionregistration.k8s.io",
+	)
+	if diff := cmp.Diff(sets.List(expected), sets.List(grs)); diff != "" {
+		t.Fatalf("unexpected API groups: +want, -got\n%s", diff)
+	}
+
+	t.Logf("Create cluster scoped resource: namespace %q", "test")
+	if _, err := client.CoreV1().Namespaces().Create(ctx, &corev1.Namespace{ObjectMeta: metav1.ObjectMeta{Name: "test"}}, metav1.CreateOptions{}); err != nil {
+		t.Fatal(err)
+	}
+
+	t.Logf("Create namesapces resource: configmap %q", "config")
+	if _, err := client.CoreV1().ConfigMaps("test").Create(ctx, &corev1.ConfigMap{
+		ObjectMeta: metav1.ObjectMeta{Namespace: "test", Name: "config"},
+		Data:       map[string]string{"foo": "bar"},
+	}, metav1.CreateOptions{}); err != nil {
+		t.Fatal(err)
+	}
+
+	t.Logf("Create CRD")
+	etcd.CreateTestCRDs(t, apiextensionsclientset.NewForConfigOrDie(server.ClientConfig), false, etcd.GetCustomResourceDefinitionData()...)
+	if _, err := dynamicClient.Resource(schema.GroupVersionResource{Group: "awesome.bears.com", Version: "v1", Resource: "pandas"}).Create(ctx, &unstructured.Unstructured{
+		Object: map[string]interface{}{
+			"apiVersion": "awesome.bears.com/v1",
+			"kind":       "Panda",
+			"metadata": map[string]interface{}{
+				"name": "baobao",
+			},
+		},
+	}, metav1.CreateOptions{}); err != nil {
+		t.Error(err)
+	}
+}