replace contrustor of ad controller with config.complete.new flow

review:
1. import order
2. only set nil field on complete
3. replace hardcoded default namespace

cmd/kube-apiserver/app/BUILD

@@ -1,9 +1,4 @@
-package(default_visibility = ["//visibility:public"])
-
-load(
-    "@io_bazel_rules_go//go:def.bzl",
-    "go_library",
-)
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
 go_library(
     name = "go_default_library",
@@ -13,6 +8,7 @@ go_library(
         "server.go",
     ],
     importpath = "k8s.io/kubernetes/cmd/kube-apiserver/app",
+    visibility = ["//visibility:public"],
     deps = [
         "//cmd/kube-apiserver/app/options:go_default_library",
         "//pkg/api/legacyscheme:go_default_library",
@@ -32,7 +28,6 @@ go_library(
         "//pkg/master/controller/crdregistration:go_default_library",
         "//pkg/master/reconcilers:go_default_library",
         "//pkg/master/tunneler:go_default_library",
-        "//pkg/quota/v1/install:go_default_library",
         "//pkg/registry/cachesize:go_default_library",
         "//pkg/registry/rbac/rest:go_default_library",
         "//pkg/serviceaccount:go_default_library",
@@ -53,7 +48,6 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/util/sets:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/wait:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/admission:go_default_library",
-        "//staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/initializer:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/authentication/authenticator:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/authorization/authorizer:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/endpoints/openapi:go_default_library",
@@ -67,11 +61,8 @@ go_library(
         "//staging/src/k8s.io/apiserver/pkg/util/feature:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/util/flag:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/util/webhook:go_default_library",
-        "//staging/src/k8s.io/client-go/discovery/cached:go_default_library",
         "//staging/src/k8s.io/client-go/informers:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes:go_default_library",
-        "//staging/src/k8s.io/client-go/rest:go_default_library",
-        "//staging/src/k8s.io/client-go/restmapper:go_default_library",
         "//staging/src/k8s.io/client-go/tools/cache:go_default_library",
         "//staging/src/k8s.io/client-go/util/cert:go_default_library",
         "//staging/src/k8s.io/cloud-provider:go_default_library",
@@ -105,4 +96,5 @@ filegroup(
         "//cmd/kube-apiserver/app/testing:all-srcs",
     ],
     tags = ["automanaged"],
+    visibility = ["//visibility:public"],
 )

cmd/kube-apiserver/app/server.go

@@ -42,7 +42,6 @@ import (
 	"k8s.io/apimachinery/pkg/util/sets"
 	utilwait "k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/apiserver/pkg/admission"
-	webhookinit "k8s.io/apiserver/pkg/admission/plugin/webhook/initializer"
 	"k8s.io/apiserver/pkg/authentication/authenticator"
 	"k8s.io/apiserver/pkg/authorization/authorizer"
 	openapinamer "k8s.io/apiserver/pkg/endpoints/openapi"
@@ -54,11 +53,8 @@ import (
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	apiserverflag "k8s.io/apiserver/pkg/util/flag"
 	"k8s.io/apiserver/pkg/util/webhook"
-	cacheddiscovery "k8s.io/client-go/discovery/cached"
 	clientgoinformers "k8s.io/client-go/informers"
 	clientgoclientset "k8s.io/client-go/kubernetes"
-	"k8s.io/client-go/rest"
-	"k8s.io/client-go/restmapper"
 	certutil "k8s.io/client-go/util/cert"
 	cloudprovider "k8s.io/cloud-provider"
 	aggregatorapiserver "k8s.io/kube-aggregator/pkg/apiserver"
@@ -81,7 +77,6 @@ import (
 	"k8s.io/kubernetes/pkg/master"
 	"k8s.io/kubernetes/pkg/master/reconcilers"
 	"k8s.io/kubernetes/pkg/master/tunneler"
-	quotainstall "k8s.io/kubernetes/pkg/quota/v1/install"
 	"k8s.io/kubernetes/pkg/registry/cachesize"
 	rbacrest "k8s.io/kubernetes/pkg/registry/rbac/rest"
 	"k8s.io/kubernetes/pkg/serviceaccount"
@@ -506,24 +501,6 @@ func buildGenericConfig(
 	}
 	versionedInformers = clientgoinformers.NewSharedInformerFactory(clientgoExternalClient, 10*time.Minute)
 
-	if s.EnableAggregatorRouting {
-		serviceResolver = aggregatorapiserver.NewEndpointServiceResolver(
-			versionedInformers.Core().V1().Services().Lister(),
-			versionedInformers.Core().V1().Endpoints().Lister(),
-		)
-	} else {
-		serviceResolver = aggregatorapiserver.NewClusterIPServiceResolver(
-			versionedInformers.Core().V1().Services().Lister(),
-		)
-	}
-	// resolve kubernetes.default.svc locally
-	localHost, err := url.Parse(genericConfig.LoopbackClientConfig.Host)
-	if err != nil {
-		lastErr = err
-		return
-	}
-	serviceResolver = aggregatorapiserver.NewLoopbackServiceResolver(serviceResolver, localHost)
-
 	genericConfig.Authentication.Authenticator, genericConfig.OpenAPIConfig.SecurityDefinitions, err = BuildAuthenticator(s, clientgoExternalClient, versionedInformers)
 	if err != nil {
 		lastErr = fmt.Errorf("invalid authentication config: %v", err)
@@ -539,35 +516,14 @@ func buildGenericConfig(
 		genericConfig.DisabledPostStartHooks.Insert(rbacrest.PostStartHookName)
 	}
 
-	webhookAuthResolverWrapper := func(delegate webhook.AuthenticationInfoResolver) webhook.AuthenticationInfoResolver {
-		return &webhook.AuthenticationInfoResolverDelegator{
-			ClientConfigForFunc: func(server string) (*rest.Config, error) {
-				if server == "kubernetes.default.svc" {
-					return genericConfig.LoopbackClientConfig, nil
-				}
-				return delegate.ClientConfigFor(server)
-			},
-			ClientConfigForServiceFunc: func(serviceName, serviceNamespace string) (*rest.Config, error) {
-				if serviceName == "kubernetes" && serviceNamespace == "default" {
-					return genericConfig.LoopbackClientConfig, nil
-				}
-				ret, err := delegate.ClientConfigForService(serviceName, serviceNamespace)
-				if err != nil {
-					return nil, err
-				}
-				if proxyTransport != nil && proxyTransport.DialContext != nil {
-					ret.Dial = proxyTransport.DialContext
-				}
-				return ret, err
-			},
-		}
+	admissionConfig := &kubeapiserveradmission.AdmissionConfig{
+		ExternalInformers:    versionedInformers,
+		LoopbackClientConfig: genericConfig.LoopbackClientConfig,
+		CloudConfigFile:      s.CloudProvider.CloudConfigFile,
 	}
-	pluginInitializers, admissionPostStartHook, err = BuildAdmissionPluginInitializers(
-		s,
-		client,
-		serviceResolver,
-		webhookAuthResolverWrapper,
-	)
+	serviceResolver = buildServiceResolver(s.EnableAggregatorRouting, genericConfig.LoopbackClientConfig.Host, versionedInformers)
+
+	pluginInitializers, admissionPostStartHook, err = admissionConfig.New(proxyTransport, serviceResolver)
 	if err != nil {
 		lastErr = fmt.Errorf("failed to create admission plugin initializer: %v", err)
 		return
@@ -586,42 +542,6 @@ func buildGenericConfig(
 	return
 }
 
-// BuildAdmissionPluginInitializers constructs the admission plugin initializer
-func BuildAdmissionPluginInitializers(
-	s *options.ServerRunOptions,
-	client internalclientset.Interface,
-	serviceResolver aggregatorapiserver.ServiceResolver,
-	webhookAuthWrapper webhook.AuthenticationInfoResolverWrapper,
-) ([]admission.PluginInitializer, genericapiserver.PostStartHookFunc, error) {
-	var cloudConfig []byte
-
-	if s.CloudProvider.CloudConfigFile != "" {
-		var err error
-		cloudConfig, err = ioutil.ReadFile(s.CloudProvider.CloudConfigFile)
-		if err != nil {
-			glog.Fatalf("Error reading from cloud configuration file %s: %#v", s.CloudProvider.CloudConfigFile, err)
-		}
-	}
-
-	// We have a functional client so we can use that to build our discovery backed REST mapper
-	// Use a discovery client capable of being refreshed.
-	discoveryClient := cacheddiscovery.NewMemCacheClient(client.Discovery())
-	discoveryRESTMapper := restmapper.NewDeferredDiscoveryRESTMapper(discoveryClient)
-
-	admissionPostStartHook := func(context genericapiserver.PostStartHookContext) error {
-		discoveryRESTMapper.Reset()
-		go utilwait.Until(discoveryRESTMapper.Reset, 30*time.Second, context.StopCh)
-		return nil
-	}
-
-	quotaConfiguration := quotainstall.NewQuotaConfigurationForAdmission()
-
-	kubePluginInitializer := kubeapiserveradmission.NewPluginInitializer(cloudConfig, discoveryRESTMapper, quotaConfiguration)
-	webhookPluginInitializer := webhookinit.NewPluginInitializer(webhookAuthWrapper, serviceResolver)
-
-	return []admission.PluginInitializer{webhookPluginInitializer, kubePluginInitializer}, admissionPostStartHook, nil
-}
-
 // BuildAuthenticator constructs the authenticator
 func BuildAuthenticator(s *options.ServerRunOptions, extclient clientgoclientset.Interface, versionedInformer clientgoinformers.SharedInformerFactory) (authenticator.Request, *spec.SecurityDefinitions, error) {
 	authenticatorConfig := s.Authentication.ToAuthenticationConfig()
@@ -728,6 +648,25 @@ func Complete(s *options.ServerRunOptions) (completedServerRunOptions, error) {
 	return options, nil
 }
 
+func buildServiceResolver(enabledAggregatorRouting bool, hostname string, informer clientgoinformers.SharedInformerFactory) webhook.ServiceResolver {
+	var serviceResolver webhook.ServiceResolver
+	if enabledAggregatorRouting {
+		serviceResolver = aggregatorapiserver.NewEndpointServiceResolver(
+			informer.Core().V1().Services().Lister(),
+			informer.Core().V1().Endpoints().Lister(),
+		)
+	} else {
+		serviceResolver = aggregatorapiserver.NewClusterIPServiceResolver(
+			informer.Core().V1().Services().Lister(),
+		)
+	}
+	// resolve kubernetes.default.svc locally
+	if localHost, err := url.Parse(hostname); err == nil {
+		serviceResolver = aggregatorapiserver.NewLoopbackServiceResolver(serviceResolver, localHost)
+	}
+	return serviceResolver
+}
+
 func readCAorNil(file string) ([]byte, error) {
 	if len(file) == 0 {
 		return nil, nil

pkg/kubeapiserver/admission/BUILD

@@ -1,9 +1,32 @@
-package(default_visibility = ["//visibility:public"])
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
 
-load(
-    "@io_bazel_rules_go//go:def.bzl",
-    "go_library",
-    "go_test",
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "config.go",
+        "initializer.go",
+    ],
+    importpath = "k8s.io/kubernetes/pkg/kubeapiserver/admission",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//pkg/client/clientset_generated/internalclientset:go_default_library",
+        "//pkg/client/informers/informers_generated/internalversion:go_default_library",
+        "//pkg/quota/v1:go_default_library",
+        "//pkg/quota/v1/install:go_default_library",
+        "//staging/src/k8s.io/api/core/v1:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/api/meta:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/util/wait:go_default_library",
+        "//staging/src/k8s.io/apiserver/pkg/admission:go_default_library",
+        "//staging/src/k8s.io/apiserver/pkg/admission/plugin/webhook/initializer:go_default_library",
+        "//staging/src/k8s.io/apiserver/pkg/authorization/authorizer:go_default_library",
+        "//staging/src/k8s.io/apiserver/pkg/server:go_default_library",
+        "//staging/src/k8s.io/apiserver/pkg/util/webhook:go_default_library",
+        "//staging/src/k8s.io/client-go/discovery/cached:go_default_library",
+        "//staging/src/k8s.io/client-go/informers:go_default_library",
+        "//staging/src/k8s.io/client-go/rest:go_default_library",
+        "//staging/src/k8s.io/client-go/restmapper:go_default_library",
+        "//vendor/github.com/golang/glog:go_default_library",
+    ],
 )
 
 go_test(
@@ -13,19 +36,6 @@ go_test(
     deps = ["//staging/src/k8s.io/apiserver/pkg/admission:go_default_library"],
 )
 
-go_library(
-    name = "go_default_library",
-    srcs = ["initializer.go"],
-    importpath = "k8s.io/kubernetes/pkg/kubeapiserver/admission",
-    deps = [
-        "//pkg/quota/v1:go_default_library",
-        "//staging/src/k8s.io/apimachinery/pkg/api/meta:go_default_library",
-        "//staging/src/k8s.io/apiserver/pkg/admission:go_default_library",
-        "//staging/src/k8s.io/apiserver/pkg/authorization/authorizer:go_default_library",
-        "//staging/src/k8s.io/apiserver/pkg/util/webhook:go_default_library",
-    ],
-)
-
 filegroup(
     name = "package-srcs",
     srcs = glob(["**"]),
@@ -40,4 +50,5 @@ filegroup(
         "//pkg/kubeapiserver/admission/util:all-srcs",
     ],
     tags = ["automanaged"],
+    visibility = ["//visibility:public"],
 )

pkg/kubeapiserver/admission/config.go

@@ -0,0 +1,108 @@
+/*
+Copyright 2018 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 admission
+
+import (
+	"io/ioutil"
+	"net/http"
+	"time"
+
+	"github.com/golang/glog"
+
+	"k8s.io/api/core/v1"
+	utilwait "k8s.io/apimachinery/pkg/util/wait"
+	"k8s.io/apiserver/pkg/admission"
+	webhookinit "k8s.io/apiserver/pkg/admission/plugin/webhook/initializer"
+	"k8s.io/apiserver/pkg/server"
+	genericapiserver "k8s.io/apiserver/pkg/server"
+	"k8s.io/apiserver/pkg/util/webhook"
+	cacheddiscovery "k8s.io/client-go/discovery/cached"
+	externalinformers "k8s.io/client-go/informers"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/restmapper"
+	"k8s.io/kubernetes/pkg/client/clientset_generated/internalclientset"
+	internalinformers "k8s.io/kubernetes/pkg/client/informers/informers_generated/internalversion"
+	quotainstall "k8s.io/kubernetes/pkg/quota/v1/install"
+)
+
+type AdmissionConfig struct {
+	CloudConfigFile      string
+	LoopbackClientConfig *rest.Config
+	ExternalInformers    externalinformers.SharedInformerFactory
+	InternalInformers    internalinformers.SharedInformerFactory
+}
+
+func (c *AdmissionConfig) buildAuthnInfoResolver(proxyTransport *http.Transport) webhook.AuthenticationInfoResolverWrapper {
+	webhookAuthResolverWrapper := func(delegate webhook.AuthenticationInfoResolver) webhook.AuthenticationInfoResolver {
+		return &webhook.AuthenticationInfoResolverDelegator{
+			ClientConfigForFunc: func(server string) (*rest.Config, error) {
+				if server == "kubernetes.default.svc" {
+					return c.LoopbackClientConfig, nil
+				}
+				return delegate.ClientConfigFor(server)
+			},
+			ClientConfigForServiceFunc: func(serviceName, serviceNamespace string) (*rest.Config, error) {
+				if serviceName == "kubernetes" && serviceNamespace == v1.NamespaceDefault {
+					return c.LoopbackClientConfig, nil
+				}
+				ret, err := delegate.ClientConfigForService(serviceName, serviceNamespace)
+				if err != nil {
+					return nil, err
+				}
+				if proxyTransport != nil && proxyTransport.DialContext != nil {
+					ret.Dial = proxyTransport.DialContext
+				}
+				return ret, err
+			},
+		}
+	}
+	return webhookAuthResolverWrapper
+}
+
+func (c *AdmissionConfig) New(proxyTransport *http.Transport, serviceResolver webhook.ServiceResolver) ([]admission.PluginInitializer, server.PostStartHookFunc, error) {
+	webhookAuthResolverWrapper := c.buildAuthnInfoResolver(proxyTransport)
+	webhookPluginInitializer := webhookinit.NewPluginInitializer(webhookAuthResolverWrapper, serviceResolver)
+
+	var cloudConfig []byte
+	if c.CloudConfigFile != "" {
+		var err error
+		cloudConfig, err = ioutil.ReadFile(c.CloudConfigFile)
+		if err != nil {
+			glog.Fatalf("Error reading from cloud configuration file %s: %#v", c.CloudConfigFile, err)
+		}
+	}
+	internalClient, err := internalclientset.NewForConfig(c.LoopbackClientConfig)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	discoveryClient := cacheddiscovery.NewMemCacheClient(internalClient.Discovery())
+	discoveryRESTMapper := restmapper.NewDeferredDiscoveryRESTMapper(discoveryClient)
+	kubePluginInitializer := NewPluginInitializer(
+		cloudConfig,
+		discoveryRESTMapper,
+		quotainstall.NewQuotaConfigurationForAdmission(),
+	)
+
+	admissionPostStartHook := func(context genericapiserver.PostStartHookContext) error {
+		discoveryRESTMapper.Reset()
+		go utilwait.Until(discoveryRESTMapper.Reset, 30*time.Second, context.StopCh)
+		return nil
+	}
+
+	return []admission.PluginInitializer{webhookPluginInitializer, kubePluginInitializer}, admissionPostStartHook, nil
+}