Remove istio

main.go

// Note: the example only works with the code within the same release/branch.
package main

import (
	"flag"
	"os"
	"path/filepath"
	"strings"

	"go.uber.org/zap"
	"k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/client-go/kubernetes"
	"k8s.io/client-go/tools/clientcmd"
	// Uncomment the following line to load the gcp plugin (only required to authenticate against GKE clusters).
	_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
)

func main() {
	logger, _ := zap.NewDevelopment()
	defer logger.Sync() // flushes buffer, if any
	sugar := logger.Sugar()

	var kubeconfig *string
	if home := homeDir(); home != "" {
		kubeconfig = flag.String("kubeconfig", filepath.Join(home, ".kube", "config"), "(optional) absolute path to the kubeconfig file")
	} else {
		kubeconfig = flag.String("kubeconfig", "", "absolute path to the kubeconfig file")
	}
	flag.Parse()

	// use the current context in kubeconfig
	config, err := clientcmd.BuildConfigFromFlags("", *kubeconfig)
	if err != nil {
		panic(err.Error())
	}

	// create the clientset
	clientset, err := kubernetes.NewForConfig(config)
	if err != nil {
		panic(err.Error())
	}

	dpls, err := clientset.AppsV1beta1().Deployments("default").List(metav1.ListOptions{})
	if err != nil {
		panic(err.Error())
	}

	for _, d := range dpls.Items {
		update := false

		if os.Getenv("DEPLOYMENT") != "" && d.Name != os.Getenv("DEPLOYMENT") {
			continue
		}

		conts := d.Spec.Template.Spec.Containers
		for i, c := range d.Spec.Template.Spec.Containers {
			if c.Name == "istio-proxy" {
				conts = append(conts[:i], conts[i+1:]...)
				update = true
			}
		}

		vols := d.Spec.Template.Spec.Volumes
		deleted := 0
		for i, v := range d.Spec.Template.Spec.Volumes {
			if strings.Contains(v.Name, "istio") {
				j := i - deleted
				vols = append(vols[:j], vols[j+1:]...)
				deleted++
				update = true
			}
		}

		anons := d.Spec.Template.Annotations
		for k, _ := range d.Spec.Template.Annotations {
			if strings.Contains(k, "istio") {
				delete(anons, k)
				update = true
			}

			if strings.Contains(k, "init-containers") {
				delete(anons, k)
				update = true
			}
		}

		if update {
			sugar.Infof("Updating deployment %s", d.Name)
			d.Spec.Template.Spec.Containers = conts
			d.Spec.Template.Spec.Volumes = vols
			d.Spec.Template.Annotations = anons
			d.Spec.Template.Spec.InitContainers = []v1.Container{}

			clientset.AppsV1beta1().Deployments("default").Update(&d)
		} else {
			sugar.Infof("Skipping deployment %s", d.Name)
		}
	}
}

func homeDir() string {
	if h := os.Getenv("HOME"); h != "" {
		return h
	}
	return os.Getenv("USERPROFILE") // windows
}