remove svc from mesh (istio#16646)

istioctl/cmd/remove-from-mesh.go

@@ -0,0 +1,213 @@
+// Copyright 2019 Istio 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 cmd
+
+import (
+	"fmt"
+	"io"
+	"strings"
+
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/client-go/dynamic"
+
+	"istio.io/istio/pkg/config/schemas"
+
+	"github.com/spf13/cobra"
+	"go.uber.org/multierr"
+	"k8s.io/client-go/kubernetes"
+
+	"istio.io/istio/istioctl/pkg/util/handlers"
+	"istio.io/pkg/log"
+
+	appsv1 "k8s.io/api/apps/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+func removeFromMeshCmd() *cobra.Command {
+	addToMeshCmd := &cobra.Command{
+		Use:     "remove-from-mesh",
+		Aliases: []string{"remove"},
+		Short:   "Remove workloads from Istio service mesh",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			cmd.HelpFunc()(cmd, args)
+			if len(args) != 0 {
+				return fmt.Errorf("unknown resource type %q", args[0])
+			}
+			return nil
+		},
+	}
+	addToMeshCmd.AddCommand(svcUnMeshifyCmd())
+	addToMeshCmd.AddCommand(externalSvcUnMeshifyCmd())
+	return addToMeshCmd
+}
+
+func svcUnMeshifyCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "service",
+		Short: "Remove Service from Istio service mesh",
+		Long: `istioctl experimental remove-from-mesh service restarts pods with the Istio sidecar un-injected.
+THIS COMMAND IS STILL UNDER ACTIVE DEVELOPMENT AND NOT READY FOR PRODUCTION USE.
+`,
+		Example: `istioctl experimental remove-from-mesh service productpage`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			if len(args) != 1 {
+				return fmt.Errorf("expecting service name")
+			}
+			client, err := interfaceFactory(kubeconfig)
+			if err != nil {
+				return err
+			}
+			ns := handlers.HandleNamespace(namespace, defaultNamespace)
+			writer := cmd.OutOrStdout()
+			_, err = client.CoreV1().Services(ns).Get(args[0], metav1.GetOptions{})
+			if err != nil {
+				return fmt.Errorf("service %q does not exist, skip", args[0])
+			}
+			matchingDeployments, err := findDeploymentsForSvc(client, ns, args[0])
+			if err != nil {
+				return err
+			}
+			if len(matchingDeployments) == 0 {
+				fmt.Fprintf(writer, "No deployments found for service %s.%s\n", args[0], ns)
+				return nil
+			}
+			return unInjectSideCarFromDeployment(client, matchingDeployments, args[0], ns, writer)
+		},
+	}
+	return cmd
+}
+
+func externalSvcUnMeshifyCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "external-service <svcname>",
+		Short: "Remove Service Entry and Kubernetes Service for the external service from Istio service mesh",
+		Long: `istioctl experimental remove-from-mesh external-service remove the ServiceEntry and\ 
+the kubernetes Service for the specified external service(eg:services running on VM) from Istio service mesh.
+The typical usage scenario is Mesh Expansion on VMs.
+THIS COMMAND IS STILL UNDER ACTIVE DEVELOPMENT AND NOT READY FOR PRODUCTION USE.
+`,
+		Example: `istioctl experimental remove-from-mesh external-service vmhttp`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			if len(args) != 1 {
+				return fmt.Errorf("expecting external service name")
+			}
+			client, err := interfaceFactory(kubeconfig)
+			if err != nil {
+				return err
+			}
+			seClient, err := crdFactory(kubeconfig)
+			if err != nil {
+				return err
+			}
+			writer := cmd.OutOrStdout()
+			ns := handlers.HandleNamespace(namespace, defaultNamespace)
+			_, err = client.CoreV1().Services(ns).Get(args[0], metav1.GetOptions{
+				IncludeUninitialized: true})
+			if err == nil {
+				return removeServiceOnVMFromMesh(seClient, client, ns, args[0], writer)
+			}
+			return fmt.Errorf("service %q does not exist, skip", args[0])
+		},
+	}
+	return cmd
+}
+
+func unInjectSideCarFromDeployment(client kubernetes.Interface, deps []appsv1.Deployment,
+	svcName, svcNamespace string, writer io.Writer) error {
+	var errs error
+	name := strings.Join([]string{svcName, svcNamespace}, ".")
+	for _, dep := range deps {
+		log.Debugf("updating deployment %s.%s with Istio sidecar un-injected",
+			dep.Name, dep.Namespace)
+		podSpec := dep.Spec.Template.Spec.DeepCopy()
+		newDep := dep.DeepCopyObject()
+		depName := strings.Join([]string{dep.Name, dep.Namespace}, ".")
+		sidecarInjected := false
+		for _, c := range podSpec.Containers {
+			if c.Name == proxyContainerName {
+				sidecarInjected = true
+				break
+			}
+		}
+		if !sidecarInjected {
+			fmt.Fprintf(writer, "deployment %q has no Istio sidecar injected. Skip\n", depName)
+			continue
+		}
+		podSpec.InitContainers = removeInjectedContainers(podSpec.InitContainers, initContainerName)
+		podSpec.InitContainers = removeInjectedContainers(podSpec.InitContainers, enableCoreDumpContainerName)
+		podSpec.Containers = removeInjectedContainers(podSpec.Containers, proxyContainerName)
+		podSpec.Volumes = removeInjectedVolumes(podSpec.Volumes, envoyVolumeName)
+		podSpec.Volumes = removeInjectedVolumes(podSpec.Volumes, certVolumeName)
+		removeDNSConfig(podSpec.DNSConfig)
+		res, b := newDep.(*appsv1.Deployment)
+		if !b {
+			errs = multierr.Append(fmt.Errorf("failed to update deployment %q for service %q", depName, name), errs)
+			continue
+		}
+		res.Spec.Template.Spec = *podSpec
+		if _, err :=
+			client.AppsV1().Deployments(svcNamespace).Update(res); err != nil {
+			errs = multierr.Append(fmt.Errorf("failed to update deployment %q for service %q", depName, name), errs)
+			continue
+
+		}
+		d := &appsv1.Deployment{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      dep.Name,
+				Namespace: dep.Namespace,
+				UID:       dep.UID,
+			},
+		}
+		if _, err := client.AppsV1().Deployments(svcNamespace).UpdateStatus(d); err != nil {
+			errs = multierr.Append(fmt.Errorf("failed to update deployment %q for service %q", depName, name), errs)
+			continue
+		}
+		fmt.Fprintf(writer, "deployment %q updated successfully with Istio sidecar un-injected.\n", depName)
+	}
+	return errs
+}
+
+// removeServiceOnVMFromMesh removes the Service Entry and K8s service for the specified external service
+func removeServiceOnVMFromMesh(dynamicClient dynamic.Interface, client kubernetes.Interface, ns string,
+	svcName string, writer io.Writer) error {
+	// Pre-check Kubernetes service and service entry does not exist.
+	_, err := client.CoreV1().Services(ns).Get(svcName, metav1.GetOptions{
+		IncludeUninitialized: true,
+	})
+	if err != nil {
+		return fmt.Errorf("service %q does not exist, skip", svcName)
+	}
+	serviceEntryGVR := schema.GroupVersionResource{
+		Group:    "networking.istio.io",
+		Version:  schemas.ServiceEntry.Version,
+		Resource: "serviceentries",
+	}
+	_, err = dynamicClient.Resource(serviceEntryGVR).Namespace(ns).Get(resourceName(svcName), metav1.GetOptions{})
+	if err != nil {
+		return fmt.Errorf("service entry %q does not exist, skip", resourceName(svcName))
+	}
+	err = client.CoreV1().Services(ns).Delete(svcName, &metav1.DeleteOptions{})
+	if err != nil {
+		return fmt.Errorf("failed to delete Kubernetes service %q due to %v", svcName, err)
+	}
+	name := strings.Join([]string{svcName, ns}, ".")
+	fmt.Fprintf(writer, "Kubernetes Service %q has been deleted for external service %q\n", name, svcName)
+	err = dynamicClient.Resource(serviceEntryGVR).Namespace(ns).Delete(resourceName(svcName), &metav1.DeleteOptions{})
+	if err != nil {
+		return fmt.Errorf("failed to delete service entry %q due to %v", resourceName(svcName), err)
+	}
+	fmt.Fprintf(writer, "Service Entry %q has been deleted for external service %q\n", resourceName(svcName), svcName)
+	return nil
+}