Add MutatingWebhookConfiguration type

Kubernetes-commit: fc5a613c17c81fdda54158d58a19bd6089ae9882

pkg/admission/configuration/mutating_webhook_manager.go

@@ -0,0 +1,101 @@
+/*
+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 configuration
+
+import (
+	"fmt"
+	"reflect"
+	"sort"
+
+	"github.com/golang/glog"
+
+	"k8s.io/api/admissionregistration/v1alpha1"
+	"k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+)
+
+type MutatingWebhookConfigurationLister interface {
+	List(opts metav1.ListOptions) (*v1alpha1.MutatingWebhookConfigurationList, error)
+}
+
+// MutatingWebhookConfigurationManager collects the mutating webhook objects so that they can be called.
+type MutatingWebhookConfigurationManager struct {
+	*poller
+}
+
+func NewMutatingWebhookConfigurationManager(c MutatingWebhookConfigurationLister) *MutatingWebhookConfigurationManager {
+	getFn := func() (runtime.Object, error) {
+		list, err := c.List(metav1.ListOptions{})
+		if err != nil {
+			if errors.IsNotFound(err) || errors.IsForbidden(err) {
+				glog.V(5).Infof("MutatingWebhookConfiguration are disabled due to an error: %v", err)
+				return nil, ErrDisabled
+			}
+			return nil, err
+		}
+		return mergeMutatingWebhookConfigurations(list), nil
+	}
+
+	return &MutatingWebhookConfigurationManager{
+		newPoller(getFn),
+	}
+}
+
+// Webhooks returns the merged MutatingWebhookConfiguration.
+func (im *MutatingWebhookConfigurationManager) Webhooks() (*v1alpha1.MutatingWebhookConfiguration, error) {
+	configuration, err := im.poller.configuration()
+	if err != nil {
+		return nil, err
+	}
+	mutatingWebhookConfiguration, ok := configuration.(*v1alpha1.MutatingWebhookConfiguration)
+	if !ok {
+		return nil, fmt.Errorf("expected type %v, got type %v", reflect.TypeOf(mutatingWebhookConfiguration), reflect.TypeOf(configuration))
+	}
+	return mutatingWebhookConfiguration, nil
+}
+
+func (im *MutatingWebhookConfigurationManager) Run(stopCh <-chan struct{}) {
+	im.poller.Run(stopCh)
+}
+
+func mergeMutatingWebhookConfigurations(
+	list *v1alpha1.MutatingWebhookConfigurationList,
+) *v1alpha1.MutatingWebhookConfiguration {
+	configurations := append([]v1alpha1.MutatingWebhookConfiguration{}, list.Items...)
+	var ret v1alpha1.MutatingWebhookConfiguration
+	// The internal order of webhooks for each configuration is provided by the user
+	// but configurations themselves can be in any order. As we are going to run these
+	// webhooks in serial, they are sorted here to have a deterministic order.
+	sort.Sort(byName(configurations))
+	for _, c := range configurations {
+		ret.Webhooks = append(ret.Webhooks, c.Webhooks...)
+	}
+	return &ret
+}
+
+// byName sorts MutatingWebhookConfiguration by name. These objects are all in
+// cluster namespace (aka no namespace) thus they all have unique names.
+type byName []v1alpha1.MutatingWebhookConfiguration
+
+func (x byName) Len() int { return len(x) }
+
+func (x byName) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+
+func (x byName) Less(i, j int) bool {
+	return x[i].ObjectMeta.Name < x[j].ObjectMeta.Name
+}

pkg/admission/configuration/mutating_webhook_manager_test.go

@@ -0,0 +1,40 @@
+/*
+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 configuration
+
+import (
+	"testing"
+
+	"k8s.io/api/admissionregistration/v1alpha1"
+	"k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+)
+
+type disabledMutatingWebhookConfigLister struct{}
+
+func (l *disabledMutatingWebhookConfigLister) List(options metav1.ListOptions) (*v1alpha1.MutatingWebhookConfigurationList, error) {
+	return nil, errors.NewNotFound(schema.GroupResource{Group: "admissionregistration", Resource: "MutatingWebhookConfigurations"}, "")
+}
+func TestMutatingWebhookConfigDisabled(t *testing.T) {
+	manager := NewMutatingWebhookConfigurationManager(&disabledMutatingWebhookConfigLister{})
+	manager.sync()
+	_, err := manager.Webhooks()
+	if err.Error() != ErrDisabled.Error() {
+		t.Errorf("expected %v, got %v", ErrDisabled, err)
+	}
+}