Merge pull request #237 from rramkumar1/target-resource-lib

Add an interface to manage target resources

pkg/target/interfaces.go

@@ -0,0 +1,25 @@
+// Copyright 2018 Google Inc.
+//
+// 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 target
+
+import (
+	extensions "k8s.io/api/extensions/v1beta1"
+)
+
+// TargetResourceManager is an interface to manage the k8s resources in "target" clusters.
+type TargetResourceManager interface {
+	EnsureTargetIngress(ing *extensions.Ingress) (*extensions.Ingress, error)
+	DeleteTargetIngress(ing *extensions.Ingress) error
+}

pkg/target/target.go

@@ -0,0 +1,71 @@
+// Copyright 2018 Google Inc.
+//
+// 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 target
+
+import (
+	"fmt"
+
+	"github.com/golang/glog"
+	extensions "k8s.io/api/extensions/v1beta1"
+	meta_v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/ingress-gce/pkg/annotations"
+	"k8s.io/ingress-gce/pkg/utils"
+)
+
+type targetResourceManager struct {
+	kubeClient kubernetes.Interface
+}
+
+func NewTargetResourceManager(kubeClient kubernetes.Interface) TargetResourceManager {
+	return &targetResourceManager{kubeClient: kubeClient}
+}
+
+var _ TargetResourceManager = &targetResourceManager{}
+
+func (m *targetResourceManager) EnsureTargetIngress(ing *extensions.Ingress) (*extensions.Ingress, error) {
+	existingIng, getErr := m.kubeClient.ExtensionsV1beta1().Ingresses(ing.Namespace).Get(ing.Name, meta_v1.GetOptions{})
+	if getErr != nil {
+		if utils.IsNotFoundError(getErr) {
+			// Add MCI annotation to "target" ingress.
+			ing.Annotations[annotations.IngressClassKey] = annotations.GceMultiIngressClass
+			actualIng, createErr := m.kubeClient.ExtensionsV1beta1().Ingresses(ing.Namespace).Create(ing)
+			if createErr != nil {
+				return nil, fmt.Errorf("Error creating target ingress %v/%v: %v", ing.Namespace, ing.Name, createErr)
+			}
+			return actualIng, nil
+		}
+	}
+	// Ignore instance group annotation while comparing ingresses.
+	ignoreAnnotations := map[string]string{instanceGroupAnnotationKey: ""}
+	if !objectMetaAndSpecEquivalent(ing, existingIng, ignoreAnnotations) {
+		glog.V(3).Infof("Target ingress %v in cluster %v differs. Overwriting... \n")
+		updatedIng, updateErr := m.kubeClient.ExtensionsV1beta1().Ingresses(ing.Namespace).Update(ing)
+		if updateErr != nil {
+			return nil, fmt.Errorf("Error updating target ingress %v/%v: %v", ing.Namespace, ing.Name, updateErr)
+		}
+		return updatedIng, nil
+	}
+	return existingIng, nil
+
+}
+
+func (m *targetResourceManager) DeleteTargetIngress(ing *extensions.Ingress) error {
+	deleteErr := m.kubeClient.ExtensionsV1beta1().Ingresses(ing.Namespace).Delete(ing.Name, &meta_v1.DeleteOptions{})
+	if deleteErr != nil {
+		return fmt.Errorf("Error deleting ingress %v/%v: %v", ing.Namespace, ing.Name, deleteErr)
+	}
+	return nil
+}

pkg/target/utils.go

@@ -0,0 +1,63 @@
+// Copyright 2018 Google Inc.
+//
+// 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 target
+
+import (
+	"reflect"
+
+	meta_v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/ingress-gce/pkg/utils"
+)
+
+var (
+	instanceGroupAnnotationKey = "ingress.gcp.kubernetes.io/instance-groups"
+)
+
+// objectMetaEquivalent checks if cluster-independent, user provided data in two given ObjectMeta are equal.
+// If in the future the ObjectMeta structure is expanded then any field that is not populated
+// by the api server should be included here.
+// Ignores annotations with keys in ignoreAnnotationKeys.
+// Note: copied from https://github.com/kubernetes/federation/blob/7951a643cebc3abdcd903eaff90d1383b43928d1/pkg/federation-controller/util/meta.go#L61
+func objectMetaEquivalent(a, b meta_v1.ObjectMeta, ignoreAnnotationKeys map[string]string) bool {
+	if a.Name != b.Name {
+		return false
+	}
+	if a.Namespace != b.Namespace {
+		return false
+	}
+	if !reflect.DeepEqual(a.Labels, b.Labels) && (len(a.Labels) != 0 || len(b.Labels) != 0) {
+		return false
+	}
+	// Remove ignoreAnnotationKeys from the list of annotations.
+	aAnnotations := utils.PruneMap(a.Annotations, ignoreAnnotationKeys)
+	bAnnotations := utils.PruneMap(b.Annotations, ignoreAnnotationKeys)
+	if !reflect.DeepEqual(aAnnotations, bAnnotations) && (len(aAnnotations) != 0 || len(bAnnotations) != 0) {
+		return false
+	}
+	return true
+}
+
+// objectMetaAndSpecEquivalent checks if cluster-independent, user provided data in ObjectMeta
+// and Spec in two given top level api objects are equivalent.
+// Ignores annotations with keys in ignoreAnnotationKeys.
+// Note: copied from https://github.com/kubernetes/federation/blob/7951a643cebc3abdcd903eaff90d1383b43928d1/pkg/federation-controller/util/meta.go#L79
+func objectMetaAndSpecEquivalent(a, b runtime.Object, ignoreAnnotationKeys map[string]string) bool {
+	objectMetaA := reflect.ValueOf(a).Elem().FieldByName("ObjectMeta").Interface().(meta_v1.ObjectMeta)
+	objectMetaB := reflect.ValueOf(b).Elem().FieldByName("ObjectMeta").Interface().(meta_v1.ObjectMeta)
+	specA := reflect.ValueOf(a).Elem().FieldByName("Spec").Interface()
+	specB := reflect.ValueOf(b).Elem().FieldByName("Spec").Interface()
+	return objectMetaEquivalent(objectMetaA, objectMetaB, ignoreAnnotationKeys) && reflect.DeepEqual(specA, specB)
+}

pkg/utils/utils.go

@@ -181,10 +181,22 @@ func BackendServiceComparablePath(url string) string {
 	return fmt.Sprintf("global/%s", path_parts[1])
 }
 
+// StringsToKeyMap returns the map representation of a list of strings.
 func StringsToKeyMap(strings []string) map[string]bool {
 	m := make(map[string]bool)
 	for _, s := range strings {
 		m[s] = true
 	}
 	return m
 }
+
+// PruneMap prunes the keys specified in ignore and returns the pruned map.
+func PruneMap(m, ignore map[string]string) map[string]string {
+	result := map[string]string{}
+	for k, v := range m {
+		if _, exists := ignore[k]; !exists {
+			result[k] = v
+		}
+	}
+	return result
+}