Revert "Remove deprecated Namespace admission plug-ins"

cluster/centos/config-default.sh

@@ -42,7 +42,7 @@ export FLANNEL_NET=${FLANNEL_NET:-"172.16.0.0/16"}
 
 # Admission Controllers to invoke prior to persisting objects in cluster
 # If we included ResourceQuota, we should keep it at the end of the list to prevent incremeting quota usage prematurely.
-export ADMISSION_CONTROL=NamespaceLifecycle,LimitRanger,ServiceAccount,SecurityContextDeny,DefaultStorageClass,ResourceQuota
+export ADMISSION_CONTROL=NamespaceLifecycle,NamespaceExists,LimitRanger,ServiceAccount,SecurityContextDeny,DefaultStorageClass,ResourceQuota
 
 # Extra options to set on the Docker command line.
 # This is useful for setting --insecure-registry for local registries.

cluster/centos/master/scripts/apiserver.sh

@@ -54,7 +54,7 @@ KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=${SERVICE_CLUSTER_IP_RANGE}"
 # --admission-control="AlwaysAdmit": Ordered list of plug-ins 
 # to do admission control of resources into cluster. 
 # Comma-delimited list of: 
-#   LimitRanger, AlwaysDeny, SecurityContextDeny, 
+#   LimitRanger, AlwaysDeny, SecurityContextDeny, NamespaceExists, 
 #   NamespaceLifecycle, NamespaceAutoProvision,
 #   AlwaysAdmit, ServiceAccount, ResourceQuota, DefaultStorageClass
 KUBE_ADMISSION_CONTROL="--admission-control=${ADMISSION_CONTROL}"

cmd/kube-apiserver/app/plugins.go

@@ -32,6 +32,8 @@ import (
 	_ "k8s.io/kubernetes/plugin/pkg/admission/imagepolicy"
 	_ "k8s.io/kubernetes/plugin/pkg/admission/initialresources"
 	_ "k8s.io/kubernetes/plugin/pkg/admission/limitranger"
+	_ "k8s.io/kubernetes/plugin/pkg/admission/namespace/autoprovision"
+	_ "k8s.io/kubernetes/plugin/pkg/admission/namespace/exists"
 	_ "k8s.io/kubernetes/plugin/pkg/admission/namespace/lifecycle"
 	_ "k8s.io/kubernetes/plugin/pkg/admission/persistentvolume/label"
 	_ "k8s.io/kubernetes/plugin/pkg/admission/resourcequota"

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

@@ -0,0 +1,100 @@
+/*
+Copyright 2014 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 autoprovision
+
+import (
+	"io"
+
+	clientset "k8s.io/kubernetes/pkg/client/clientset_generated/internalclientset"
+
+	"fmt"
+
+	"k8s.io/kubernetes/pkg/admission"
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/api/errors"
+	"k8s.io/kubernetes/pkg/controller/framework"
+	"k8s.io/kubernetes/pkg/controller/framework/informers"
+)
+
+func init() {
+	admission.RegisterPlugin("NamespaceAutoProvision", func(client clientset.Interface, config io.Reader) (admission.Interface, error) {
+		return NewProvision(client), nil
+	})
+}
+
+// provision is an implementation of admission.Interface.
+// It looks at all incoming requests in a namespace context, and if the namespace does not exist, it creates one.
+// It is useful in deployments that do not want to restrict creation of a namespace prior to its usage.
+type provision struct {
+	*admission.Handler
+	client            clientset.Interface
+	namespaceInformer framework.SharedIndexInformer
+}
+
+var _ = admission.WantsInformerFactory(&provision{})
+
+func (p *provision) Admit(a admission.Attributes) (err error) {
+	// if we're here, then we've already passed authentication, so we're allowed to do what we're trying to do
+	// if we're here, then the API server has found a route, which means that if we have a non-empty namespace
+	// its a namespaced resource.
+	if len(a.GetNamespace()) == 0 || a.GetKind().GroupKind() == api.Kind("Namespace") {
+		return nil
+	}
+	// we need to wait for our caches to warm
+	if !p.WaitForReady() {
+		return admission.NewForbidden(a, fmt.Errorf("not yet ready to handle request"))
+	}
+	namespace := &api.Namespace{
+		ObjectMeta: api.ObjectMeta{
+			Name:      a.GetNamespace(),
+			Namespace: "",
+		},
+		Status: api.NamespaceStatus{},
+	}
+	_, exists, err := p.namespaceInformer.GetStore().Get(namespace)
+	if err != nil {
+		return admission.NewForbidden(a, err)
+	}
+	if exists {
+		return nil
+	}
+	_, err = p.client.Core().Namespaces().Create(namespace)
+	if err != nil && !errors.IsAlreadyExists(err) {
+		return admission.NewForbidden(a, err)
+	}
+	return nil
+}
+
+// NewProvision creates a new namespace provision admission control handler
+func NewProvision(c clientset.Interface) admission.Interface {
+	return &provision{
+		Handler: admission.NewHandler(admission.Create),
+		client:  c,
+	}
+}
+
+func (p *provision) SetInformerFactory(f informers.SharedInformerFactory) {
+	p.namespaceInformer = f.Namespaces().Informer()
+	p.SetReadyFunc(p.namespaceInformer.HasSynced)
+}
+
+func (p *provision) Validate() error {
+	if p.namespaceInformer == nil {
+		return fmt.Errorf("missing namespaceInformer")
+	}
+	return nil
+}

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

@@ -0,0 +1,172 @@
+/*
+Copyright 2014 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 autoprovision
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"k8s.io/kubernetes/pkg/admission"
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/api/errors"
+	"k8s.io/kubernetes/pkg/api/unversioned"
+	clientset "k8s.io/kubernetes/pkg/client/clientset_generated/internalclientset"
+	"k8s.io/kubernetes/pkg/client/clientset_generated/internalclientset/fake"
+	"k8s.io/kubernetes/pkg/client/testing/core"
+	"k8s.io/kubernetes/pkg/controller/framework/informers"
+	"k8s.io/kubernetes/pkg/runtime"
+	"k8s.io/kubernetes/pkg/util/wait"
+)
+
+// newHandlerForTest returns the admission controller configured for testing.
+func newHandlerForTest(c clientset.Interface) (admission.Interface, informers.SharedInformerFactory, error) {
+	f := informers.NewSharedInformerFactory(c, 5*time.Minute)
+	handler := NewProvision(c)
+	plugins := []admission.Interface{handler}
+	pluginInitializer := admission.NewPluginInitializer(f)
+	pluginInitializer.Initialize(plugins)
+	err := admission.Validate(plugins)
+	return handler, f, err
+}
+
+// newMockClientForTest creates a mock client that returns a client configured for the specified list of namespaces.
+func newMockClientForTest(namespaces []string) *fake.Clientset {
+	mockClient := &fake.Clientset{}
+	mockClient.AddReactor("list", "namespaces", func(action core.Action) (bool, runtime.Object, error) {
+		namespaceList := &api.NamespaceList{
+			ListMeta: unversioned.ListMeta{
+				ResourceVersion: fmt.Sprintf("%d", len(namespaces)),
+			},
+		}
+		for i, ns := range namespaces {
+			namespaceList.Items = append(namespaceList.Items, api.Namespace{
+				ObjectMeta: api.ObjectMeta{
+					Name:            ns,
+					ResourceVersion: fmt.Sprintf("%d", i),
+				},
+			})
+		}
+		return true, namespaceList, nil
+	})
+	return mockClient
+}
+
+// newPod returns a new pod for the specified namespace
+func newPod(namespace string) api.Pod {
+	return api.Pod{
+		ObjectMeta: api.ObjectMeta{Name: "123", Namespace: namespace},
+		Spec: api.PodSpec{
+			Volumes:    []api.Volume{{Name: "vol"}},
+			Containers: []api.Container{{Name: "ctr", Image: "image"}},
+		},
+	}
+}
+
+// hasCreateNamespaceAction returns true if it has the create namespace action
+func hasCreateNamespaceAction(mockClient *fake.Clientset) bool {
+	for _, action := range mockClient.Actions() {
+		if action.GetVerb() == "create" && action.GetResource().Resource == "namespaces" {
+			return true
+		}
+	}
+	return false
+}
+
+// TestAdmission verifies a namespace is created on create requests for namespace managed resources
+func TestAdmission(t *testing.T) {
+	namespace := "test"
+	mockClient := newMockClientForTest([]string{})
+	handler, informerFactory, err := newHandlerForTest(mockClient)
+	if err != nil {
+		t.Errorf("unexpected error initializing handler: %v", err)
+	}
+	informerFactory.Start(wait.NeverStop)
+
+	pod := newPod(namespace)
+	err = handler.Admit(admission.NewAttributesRecord(&pod, nil, api.Kind("Pod").WithVersion("version"), pod.Namespace, pod.Name, api.Resource("pods").WithVersion("version"), "", admission.Create, nil))
+	if err != nil {
+		t.Errorf("unexpected error returned from admission handler")
+	}
+	if !hasCreateNamespaceAction(mockClient) {
+		t.Errorf("expected create namespace action")
+	}
+}
+
+// TestAdmissionNamespaceExists verifies that no client call is made when a namespace already exists
+func TestAdmissionNamespaceExists(t *testing.T) {
+	namespace := "test"
+	mockClient := newMockClientForTest([]string{namespace})
+	handler, informerFactory, err := newHandlerForTest(mockClient)
+	if err != nil {
+		t.Errorf("unexpected error initializing handler: %v", err)
+	}
+	informerFactory.Start(wait.NeverStop)
+
+	pod := newPod(namespace)
+	err = handler.Admit(admission.NewAttributesRecord(&pod, nil, api.Kind("Pod").WithVersion("version"), pod.Namespace, pod.Name, api.Resource("pods").WithVersion("version"), "", admission.Create, nil))
+	if err != nil {
+		t.Errorf("unexpected error returned from admission handler")
+	}
+	if hasCreateNamespaceAction(mockClient) {
+		t.Errorf("unexpected create namespace action")
+	}
+}
+
+// TestIgnoreAdmission validates that a request is ignored if its not a create
+func TestIgnoreAdmission(t *testing.T) {
+	namespace := "test"
+	mockClient := newMockClientForTest([]string{})
+	handler, informerFactory, err := newHandlerForTest(mockClient)
+	if err != nil {
+		t.Errorf("unexpected error initializing handler: %v", err)
+	}
+	informerFactory.Start(wait.NeverStop)
+	chainHandler := admission.NewChainHandler(handler)
+
+	pod := newPod(namespace)
+	err = chainHandler.Admit(admission.NewAttributesRecord(&pod, nil, api.Kind("Pod").WithVersion("version"), pod.Namespace, pod.Name, api.Resource("pods").WithVersion("version"), "", admission.Update, nil))
+	if err != nil {
+		t.Errorf("unexpected error returned from admission handler")
+	}
+	if hasCreateNamespaceAction(mockClient) {
+		t.Errorf("unexpected create namespace action")
+	}
+}
+
+func TestAdmissionWithLatentCache(t *testing.T) {
+	namespace := "test"
+	mockClient := newMockClientForTest([]string{})
+	mockClient.AddReactor("create", "namespaces", func(action core.Action) (bool, runtime.Object, error) {
+		return true, nil, errors.NewAlreadyExists(api.Resource("namespaces"), namespace)
+	})
+	handler, informerFactory, err := newHandlerForTest(mockClient)
+	if err != nil {
+		t.Errorf("unexpected error initializing handler: %v", err)
+	}
+	informerFactory.Start(wait.NeverStop)
+
+	pod := newPod(namespace)
+	err = handler.Admit(admission.NewAttributesRecord(&pod, nil, api.Kind("Pod").WithVersion("version"), pod.Namespace, pod.Name, api.Resource("pods").WithVersion("version"), "", admission.Create, nil))
+	if err != nil {
+		t.Errorf("unexpected error returned from admission handler")
+	}
+
+	if !hasCreateNamespaceAction(mockClient) {
+		t.Errorf("expected create namespace action")
+	}
+}