admission/webhook: move webhook initializer into plugin

cmd/kube-apiserver/app/BUILD

@@ -61,6 +61,7 @@ go_library(
         "//vendor/k8s.io/apimachinery/pkg/util/wait:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/admission:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/admission/plugin/webhook/config:go_default_library",
+        "//vendor/k8s.io/apiserver/pkg/admission/plugin/webhook/initializer:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/authentication/authenticator:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/authorization/authorizer:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/server:go_default_library",

cmd/kube-apiserver/app/server.go

@@ -55,13 +55,16 @@ import (
 	aggregatorapiserver "k8s.io/kube-aggregator/pkg/apiserver"
 	openapi "k8s.io/kube-openapi/pkg/common"
 
+	webhookinit "k8s.io/apiserver/pkg/admission/plugin/webhook/initializer"
 	"k8s.io/apiserver/pkg/storage/etcd3/preflight"
 	clientgoinformers "k8s.io/client-go/informers"
 	clientgoclientset "k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
 	"k8s.io/kubernetes/cmd/kube-apiserver/app/options"
 	"k8s.io/kubernetes/pkg/api/legacyscheme"
 	"k8s.io/kubernetes/pkg/apis/apps"
 	"k8s.io/kubernetes/pkg/apis/batch"
+	api "k8s.io/kubernetes/pkg/apis/core"
 	"k8s.io/kubernetes/pkg/apis/extensions"
 	"k8s.io/kubernetes/pkg/apis/networking"
 	"k8s.io/kubernetes/pkg/apis/storage"
@@ -86,8 +89,6 @@ import (
 	"k8s.io/kubernetes/pkg/version"
 	"k8s.io/kubernetes/plugin/pkg/auth/authenticator/token/bootstrap"
 
-	"k8s.io/client-go/rest"
-	api "k8s.io/kubernetes/pkg/apis/core"
 	_ "k8s.io/kubernetes/pkg/util/reflector/prometheus" // for reflector metric registration
 	_ "k8s.io/kubernetes/pkg/util/workqueue/prometheus" // for workqueue metric registration
 )
@@ -462,7 +463,7 @@ func BuildGenericConfig(s *options.ServerRunOptions, proxyTransport *http.Transp
 			return ret, err
 		})
 	}
-	pluginInitializer, err := BuildAdmissionPluginInitializer(
+	pluginInitializers, err := BuildAdmissionPluginInitializers(
 		s,
 		client,
 		sharedInformers,
@@ -478,7 +479,7 @@ func BuildGenericConfig(s *options.ServerRunOptions, proxyTransport *http.Transp
 		versionedInformers,
 		kubeClientConfig,
 		legacyscheme.Scheme,
-		pluginInitializer)
+		pluginInitializers...)
 	if err != nil {
 		return nil, nil, nil, nil, nil, fmt.Errorf("failed to initialize admission: %v", err)
 	}
@@ -486,8 +487,8 @@ func BuildGenericConfig(s *options.ServerRunOptions, proxyTransport *http.Transp
 	return genericConfig, sharedInformers, versionedInformers, insecureServingOptions, serviceResolver, nil
 }
 
-// BuildAdmissionPluginInitializer constructs the admission plugin initializer
+// BuildAdmissionPluginInitializers constructs the admission plugin initializer
-func BuildAdmissionPluginInitializer(s *options.ServerRunOptions, client internalclientset.Interface, sharedInformers informers.SharedInformerFactory, serviceResolver aggregatorapiserver.ServiceResolver, webhookAuthWrapper webhookconfig.AuthenticationInfoResolverWrapper) (admission.PluginInitializer, error) {
+func BuildAdmissionPluginInitializers(s *options.ServerRunOptions, client internalclientset.Interface, sharedInformers informers.SharedInformerFactory, serviceResolver aggregatorapiserver.ServiceResolver, webhookAuthWrapper webhookconfig.AuthenticationInfoResolverWrapper) ([]admission.PluginInitializer, error) {
 	var cloudConfig []byte
 
 	if s.CloudProvider.CloudConfigFile != "" {
@@ -503,9 +504,10 @@ func BuildAdmissionPluginInitializer(s *options.ServerRunOptions, client interna
 
 	quotaConfiguration := quotainstall.NewQuotaConfigurationForAdmission()
 
-	pluginInitializer := kubeapiserveradmission.NewPluginInitializer(client, sharedInformers, cloudConfig, restMapper, quotaConfiguration, webhookAuthWrapper, serviceResolver)
+	kubePluginInitializer := kubeapiserveradmission.NewPluginInitializer(client, sharedInformers, cloudConfig, restMapper, quotaConfiguration)
+	webhookPluginInitializer := webhookinit.NewPluginInitializer(webhookAuthWrapper, serviceResolver)
 
-	return pluginInitializer, nil
+	return []admission.PluginInitializer{webhookPluginInitializer, kubePluginInitializer}, nil
 }
 
 // BuildAuthenticator constructs the authenticator

pkg/kubeapiserver/admission/BUILD

@@ -8,13 +8,10 @@ load(
 
 go_test(
     name = "go_default_test",
-    srcs = ["init_test.go"],
+    srcs = ["initializer_test.go"],
     importpath = "k8s.io/kubernetes/pkg/kubeapiserver/admission",
     library = ":go_default_library",
-    deps = [
+    deps = ["//vendor/k8s.io/apiserver/pkg/admission:go_default_library"],
-        "//vendor/k8s.io/apiserver/pkg/admission:go_default_library",
-        "//vendor/k8s.io/apiserver/pkg/admission/plugin/webhook/config:go_default_library",
-    ],
 )
 
 go_library(

pkg/kubeapiserver/admission/initializer.go

@@ -17,8 +17,6 @@ limitations under the License.
 package admission
 
 import (
-	"net/url"
-
 	"k8s.io/apimachinery/pkg/api/meta"
 	"k8s.io/apiserver/pkg/admission"
 	webhookconfig "k8s.io/apiserver/pkg/admission/plugin/webhook/config"
@@ -59,25 +57,7 @@ type WantsQuotaConfiguration interface {
 	admission.InitializationValidator
 }
 
-// WantsServiceResolver defines a fuction that accepts a ServiceResolver for
+// PluginInitializer is used for initialization of the Kubernetes specific admission plugins.
-// admission plugins that need to make calls to services.
-type WantsServiceResolver interface {
-	SetServiceResolver(webhookconfig.ServiceResolver)
-}
-
-// ServiceResolver knows how to convert a service reference into an actual
-// location.
-type ServiceResolver interface {
-	ResolveEndpoint(namespace, name string) (*url.URL, error)
-}
-
-// WantsAuthenticationInfoResolverWrapper defines a function that wraps the standard AuthenticationInfoResolver
-// to allow the apiserver to control what is returned as auth info
-type WantsAuthenticationInfoResolverWrapper interface {
-	SetAuthenticationInfoResolverWrapper(webhookconfig.AuthenticationInfoResolverWrapper)
-	admission.InitializationValidator
-}
-
 type PluginInitializer struct {
 	internalClient                    internalclientset.Interface
 	externalClient                    clientset.Interface
@@ -101,17 +81,13 @@ func NewPluginInitializer(
 	cloudConfig []byte,
 	restMapper meta.RESTMapper,
 	quotaConfiguration quota.Configuration,
-	authenticationInfoResolverWrapper webhookconfig.AuthenticationInfoResolverWrapper,
-	serviceResolver webhookconfig.ServiceResolver,
 ) *PluginInitializer {
 	return &PluginInitializer{
-		internalClient:                    internalClient,
+		internalClient:     internalClient,
-		informers:                         sharedInformers,
+		informers:          sharedInformers,
-		cloudConfig:                       cloudConfig,
+		cloudConfig:        cloudConfig,
-		restMapper:                        restMapper,
+		restMapper:         restMapper,
-		quotaConfiguration:                quotaConfiguration,
+		quotaConfiguration: quotaConfiguration,
-		authenticationInfoResolverWrapper: authenticationInfoResolverWrapper,
-		serviceResolver:                   serviceResolver,
 	}
 }
 
@@ -137,14 +113,4 @@ func (i *PluginInitializer) Initialize(plugin admission.Interface) {
 	if wants, ok := plugin.(WantsQuotaConfiguration); ok {
 		wants.SetQuotaConfiguration(i.quotaConfiguration)
 	}
-
-	if wants, ok := plugin.(WantsServiceResolver); ok {
-		wants.SetServiceResolver(i.serviceResolver)
-	}
-
-	if wants, ok := plugin.(WantsAuthenticationInfoResolverWrapper); ok {
-		if i.authenticationInfoResolverWrapper != nil {
-			wants.SetAuthenticationInfoResolverWrapper(i.authenticationInfoResolverWrapper)
-		}
-	}
 }

pkg/kubeapiserver/admission/initializer_test.go

@@ -17,11 +17,9 @@ limitations under the License.
 package admission
 
 import (
-	"net/url"
 	"testing"
 
 	"k8s.io/apiserver/pkg/admission"
-	"k8s.io/apiserver/pkg/admission/plugin/webhook/config"
 )
 
 type doNothingAdmission struct{}
@@ -41,7 +39,7 @@ func (self *WantsCloudConfigAdmissionPlugin) SetCloudConfig(cloudConfig []byte)
 
 func TestCloudConfigAdmissionPlugin(t *testing.T) {
 	cloudConfig := []byte("cloud-configuration")
-	initializer := NewPluginInitializer(nil, nil, cloudConfig, nil, nil, nil, nil)
+	initializer := NewPluginInitializer(nil, nil, cloudConfig, nil, nil)
 	wantsCloudConfigAdmission := &WantsCloudConfigAdmissionPlugin{}
 	initializer.Initialize(wantsCloudConfigAdmission)
 
@@ -49,26 +47,3 @@ func TestCloudConfigAdmissionPlugin(t *testing.T) {
 		t.Errorf("Expected cloud config to be initialized but found nil")
 	}
 }
-
-type fakeServiceResolver struct{}
-
-func (f *fakeServiceResolver) ResolveEndpoint(namespace, name string) (*url.URL, error) {
-	return nil, nil
-}
-
-type serviceWanter struct {
-	doNothingAdmission
-	got ServiceResolver
-}
-
-func (s *serviceWanter) SetServiceResolver(sr config.ServiceResolver) { s.got = sr }
-
-func TestWantsServiceResolver(t *testing.T) {
-	sw := &serviceWanter{}
-	fsr := &fakeServiceResolver{}
-	i := NewPluginInitializer(nil, nil, nil, nil, nil, nil, fsr)
-	i.Initialize(sw)
-	if got, ok := sw.got.(*fakeServiceResolver); !ok || got != fsr {
-		t.Errorf("plumbing fail - %v %v#", ok, got)
-	}
-}

plugin/pkg/admission/gc/gc_admission_test.go

@@ -87,7 +87,7 @@ func newGCPermissionsEnforcement() (*gcPermissionsEnforcement, error) {
 	}
 
 	genericPluginInitializer := initializer.New(nil, nil, fakeAuthorizer{}, nil)
-	pluginInitializer := kubeadmission.NewPluginInitializer(nil, nil, nil, legacyscheme.Registry.RESTMapper(), nil, nil, nil)
+	pluginInitializer := kubeadmission.NewPluginInitializer(nil, nil, nil, legacyscheme.Registry.RESTMapper(), nil)
 	initializersChain := admission.PluginInitializers{}
 	initializersChain = append(initializersChain, genericPluginInitializer)
 	initializersChain = append(initializersChain, pluginInitializer)

plugin/pkg/admission/limitranger/admission_test.go

@@ -760,7 +760,7 @@ func newHandlerForTest(c clientset.Interface) (*LimitRanger, informers.SharedInf
 	if err != nil {
 		return nil, f, err
 	}
-	pluginInitializer := kubeadmission.NewPluginInitializer(c, f, nil, nil, nil, nil, nil)
+	pluginInitializer := kubeadmission.NewPluginInitializer(c, f, nil, nil, nil)
 	pluginInitializer.Initialize(handler)
 	err = admission.ValidateInitialization(handler)
 	return handler, f, err

plugin/pkg/admission/namespace/autoprovision/admission_test.go

@@ -38,7 +38,7 @@ import (
 func newHandlerForTest(c clientset.Interface) (admission.MutationInterface, informers.SharedInformerFactory, error) {
 	f := informers.NewSharedInformerFactory(c, 5*time.Minute)
 	handler := NewProvision()
-	pluginInitializer := kubeadmission.NewPluginInitializer(c, f, nil, nil, nil, nil, nil)
+	pluginInitializer := kubeadmission.NewPluginInitializer(c, f, nil, nil, nil)
 	pluginInitializer.Initialize(handler)
 	err := admission.ValidateInitialization(handler)
 	return handler, f, err

plugin/pkg/admission/namespace/exists/admission_test.go

@@ -37,7 +37,7 @@ import (
 func newHandlerForTest(c clientset.Interface) (admission.ValidationInterface, informers.SharedInformerFactory, error) {
 	f := informers.NewSharedInformerFactory(c, 5*time.Minute)
 	handler := NewExists()
-	pluginInitializer := kubeadmission.NewPluginInitializer(c, f, nil, nil, nil, nil, nil)
+	pluginInitializer := kubeadmission.NewPluginInitializer(c, f, nil, nil, nil)
 	pluginInitializer.Initialize(handler)
 	err := admission.ValidateInitialization(handler)
 	return handler, f, err

plugin/pkg/admission/podnodeselector/admission_test.go

@@ -253,7 +253,7 @@ func TestIgnoreUpdatingInitializedPod(t *testing.T) {
 func newHandlerForTest(c clientset.Interface) (*podNodeSelector, informers.SharedInformerFactory, error) {
 	f := informers.NewSharedInformerFactory(c, 5*time.Minute)
 	handler := NewPodNodeSelector(nil)
-	pluginInitializer := kubeadmission.NewPluginInitializer(c, f, nil, nil, nil, nil, nil)
+	pluginInitializer := kubeadmission.NewPluginInitializer(c, f, nil, nil, nil)
 	pluginInitializer.Initialize(handler)
 	err := admission.ValidateInitialization(handler)
 	return handler, f, err

plugin/pkg/admission/podtolerationrestriction/admission_test.go

@@ -361,7 +361,7 @@ func newHandlerForTest(c clientset.Interface) (*podTolerationsPlugin, informers.
 		return nil, nil, err
 	}
 	handler := NewPodTolerationsPlugin(pluginConfig)
-	pluginInitializer := kubeadmission.NewPluginInitializer(c, f, nil, nil, nil, nil, nil)
+	pluginInitializer := kubeadmission.NewPluginInitializer(c, f, nil, nil, nil)
 	pluginInitializer.Initialize(handler)
 	err = admission.ValidateInitialization(handler)
 	return handler, f, err

staging/src/k8s.io/apiserver/pkg/admission/BUILD

@@ -80,6 +80,7 @@ filegroup(
         "//staging/src/k8s.io/apiserver/pkg/admission/plugin/namespace/lifecycle:all-srcs",
         "//staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/config:all-srcs",
         "//staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/errors:all-srcs",
+        "//staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/initializer:all-srcs",
         "//staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/mutating:all-srcs",
         "//staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/namespace:all-srcs",
         "//staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/request:all-srcs",

staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/initializer/BUILD

@@ -0,0 +1,37 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["initializer.go"],
+    importpath = "k8s.io/apiserver/pkg/admission/plugin/webhook/initializer",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//vendor/k8s.io/apiserver/pkg/admission:go_default_library",
+        "//vendor/k8s.io/apiserver/pkg/admission/plugin/webhook/config:go_default_library",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["initializer_test.go"],
+    importpath = "k8s.io/apiserver/pkg/admission/plugin/webhook/initializer",
+    library = ":go_default_library",
+    deps = [
+        "//vendor/k8s.io/apiserver/pkg/admission:go_default_library",
+        "//vendor/k8s.io/apiserver/pkg/admission/plugin/webhook/config:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/initializer/initializer.go

@@ -0,0 +1,76 @@
+/*
+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 initializer
+
+import (
+	"net/url"
+
+	"k8s.io/apiserver/pkg/admission"
+	webhookconfig "k8s.io/apiserver/pkg/admission/plugin/webhook/config"
+)
+
+// WantsServiceResolver defines a fuction that accepts a ServiceResolver for
+// admission plugins that need to make calls to services.
+type WantsServiceResolver interface {
+	SetServiceResolver(webhookconfig.ServiceResolver)
+}
+
+// ServiceResolver knows how to convert a service reference into an actual
+// location.
+type ServiceResolver interface {
+	ResolveEndpoint(namespace, name string) (*url.URL, error)
+}
+
+// WantsAuthenticationInfoResolverWrapper defines a function that wraps the standard AuthenticationInfoResolver
+// to allow the apiserver to control what is returned as auth info
+type WantsAuthenticationInfoResolverWrapper interface {
+	SetAuthenticationInfoResolverWrapper(webhookconfig.AuthenticationInfoResolverWrapper)
+	admission.InitializationValidator
+}
+
+// PluginInitializer is used for initialization of the webhook admission plugin.
+type PluginInitializer struct {
+	serviceResolver                   webhookconfig.ServiceResolver
+	authenticationInfoResolverWrapper webhookconfig.AuthenticationInfoResolverWrapper
+}
+
+var _ admission.PluginInitializer = &PluginInitializer{}
+
+// NewPluginInitializer constructs new instance of PluginInitializer
+func NewPluginInitializer(
+	authenticationInfoResolverWrapper webhookconfig.AuthenticationInfoResolverWrapper,
+	serviceResolver webhookconfig.ServiceResolver,
+) *PluginInitializer {
+	return &PluginInitializer{
+		authenticationInfoResolverWrapper: authenticationInfoResolverWrapper,
+		serviceResolver:                   serviceResolver,
+	}
+}
+
+// Initialize checks the initialization interfaces implemented by each plugin
+// and provide the appropriate initialization data
+func (i *PluginInitializer) Initialize(plugin admission.Interface) {
+	if wants, ok := plugin.(WantsServiceResolver); ok {
+		wants.SetServiceResolver(i.serviceResolver)
+	}
+
+	if wants, ok := plugin.(WantsAuthenticationInfoResolverWrapper); ok {
+		if i.authenticationInfoResolverWrapper != nil {
+			wants.SetAuthenticationInfoResolverWrapper(i.authenticationInfoResolverWrapper)
+		}
+	}
+}

staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/initializer/initializer_test.go

@@ -0,0 +1,54 @@
+/*
+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 initializer
+
+import (
+	"net/url"
+	"testing"
+
+	"k8s.io/apiserver/pkg/admission"
+	"k8s.io/apiserver/pkg/admission/plugin/webhook/config"
+)
+
+type doNothingAdmission struct{}
+
+func (doNothingAdmission) Admit(a admission.Attributes) error { return nil }
+func (doNothingAdmission) Handles(o admission.Operation) bool { return false }
+func (doNothingAdmission) Validate() error                    { return nil }
+
+type fakeServiceResolver struct{}
+
+func (f *fakeServiceResolver) ResolveEndpoint(namespace, name string) (*url.URL, error) {
+	return nil, nil
+}
+
+type serviceWanter struct {
+	doNothingAdmission
+	got ServiceResolver
+}
+
+func (s *serviceWanter) SetServiceResolver(sr config.ServiceResolver) { s.got = sr }
+
+func TestWantsServiceResolver(t *testing.T) {
+	sw := &serviceWanter{}
+	fsr := &fakeServiceResolver{}
+	i := NewPluginInitializer(nil, fsr)
+	i.Initialize(sw)
+	if got, ok := sw.got.(*fakeServiceResolver); !ok || got != fsr {
+		t.Errorf("plumbing fail - %v %v#", ok, got)
+	}
+}