kubernetes-client-go-remote

package main

import (
	"context"
	"fmt"

	"k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/client-go/kubernetes"
	"k8s.io/client-go/rest"
)

//////////
// 참고
// https://github.com/kubernetes/client-go/tree/f6ce18ae578c8cca64d14ab9687824d9e1305a67/informers/core/v1
// https://github.com/kubernetes/client-go/blob/master/kubernetes/typed/core/v1/pod.go
// https://github.com/kubernetes/apimachinery/tree/master/pkg/apis/meta/v1
//
// https://gerrit.opnfv.org/gerrit/gitweb?p=ovn4nfv-k8s-plugin.git;hb=refs%2Fchanges%2F23%2F68323%2F4;f=internal%2Fpkg%2Fkube%2Fkube.go
// https://www.cnblogs.com/breg/p/11350174.html
// https://github.com/gedge-platform/gs-linkgw/blob/main/migration/etri.com/plugin/cmd.go
//////////

func KubernetesClient() (*kubernetes.Clientset, error) {
	config := &rest.Config{
		Host: "https://111.111.111.111:6443",
		// APIPath:         "/",
		// Prefix:          "",
		BearerToken:     "eyJhbGciOiJSUzI1NiIsImtpZCI6InJvVHROMm1OZjZNOTQ5X21QMmViYi1Cd2oyWlpsV0Y0fggkrb.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.YsoJB5Uhd9l71ophm14yPRXs5G4oB3iPFgCtoiWJ_Og7ry_VdCguzTIdtrAkb5R7kGQbKVmYa7nFOFRNPw1K01AV2SThbuO2IrnyqicLXgA6MsUXCOUk5DxG9R03EfGx4itGIzn7HvoyUqZ3L5IM3YaOvNsYcweeNL7jheVweY8joijMQ4iBsG2WGaeQ1kkYcwj_Et0tBJgBOVS_EQaL5hISTtmbhbfAUJxE1FiUjBn6XX0D8yfO5m7AIQFmjoUQK_TXvxGrOFzS1QFY9Roin-xvWfjIDhNwtlsUmHAo2f-EwpKDr381J7dSTJ7liidOl2Ad1ITl3q_ZhLRb2RIm3Q",
		TLSClientConfig: rest.TLSClientConfig{Insecure: true},
		// Username:        clstr.MasterAuth.Username,
		// Password:        clstr.MasterAuth.Password,
	}
	kbrnts, err := kubernetes.NewForConfig(config)
	if err != nil {
		return nil, err
	}
	return kbrnts, nil
}

func listNodes(client *kubernetes.Clientset) {
	nodes, err := client.CoreV1().Nodes().List(context.TODO(), metav1.ListOptions{})
	check(err)
	fmt.Printf("There are %d nodes in the cluster:\n", len(nodes.Items))
	for i, node := range nodes.Items {
		fmt.Printf("%d %s\n", i, node.GetName())
	}
}

func listNamespaces(client *kubernetes.Clientset) {
	namespacesClient := client.CoreV1().Namespaces()
	namespaces, err := namespacesClient.List(context.TODO(), metav1.ListOptions{})
	check(err)
	fmt.Printf("There are %d namespaces in the cluster:\n", len(namespaces.Items))
	for i, namespace := range namespaces.Items {
		fmt.Printf("%d %s\n", i, namespace.GetName())
	}
}

func listPods(client *kubernetes.Clientset) {
	podsClient := client.CoreV1().Pods("default")
	pods, err := podsClient.List(context.TODO(), metav1.ListOptions{})
	check(err)
	fmt.Printf("There are %d pods in the cluster:\n", len(pods.Items))
	for i, pod := range pods.Items {
		fmt.Printf("%d %s\n", i, pod.GetName())
	}
}

func listDeployments(client *kubernetes.Clientset) {
	deploymentsClient := client.AppsV1().Deployments("bookinfo")
	deployments, err := deploymentsClient.List(context.TODO(), metav1.ListOptions{})
	check(err)
	fmt.Printf("There are %d deployments in the cluster:\n", len(deployments.Items))
	for i, deployment := range deployments.Items {
		fmt.Printf("%d %s\n", i, deployment.GetName())
	}
}

func getPods(client *kubernetes.Clientset, PodName string) {
	podsClient := client.CoreV1().Pods("default")
	podInfo, err := podsClient.Get(context.TODO(), PodName, metav1.GetOptions{})
	if errors.IsNotFound(err) {
		fmt.Printf("Pod %d not found in default namespace\n", PodName)
	} else if statusError, isStatus := err.(*errors.StatusError); isStatus {
		fmt.Printf("Error getting pod %v\n", statusError.ErrStatus.Message)
	} else if err != nil {
		panic(err.Error())
	} else {
		fmt.Printf("Found %d pod in default namespace\n", PodName)
		fmt.Println("%d Infomation is : %d", PodName, podInfo)
		fmt.Println("\n\n\n\n")
		fmt.Println("ObjectMeta Name : ", podInfo.ObjectMeta.GetName())
		fmt.Println("ObjectMeta Namespace : ", podInfo.ObjectMeta.GetNamespace())
		fmt.Println("ObjectMeta Annotations : ", podInfo.ObjectMeta.GetAnnotations())
		fmt.Println("ObjectMeta Labels : ", podInfo.ObjectMeta.GetLabels())
		// fmt.Println("PodIP : %d", podInfo.Status.PodIP)
		// fmt.Println("Spec : %d", podInfo.Spec.ServiceAccountName)
	}
}

func main() {
	clientset, err := KubernetesClient()
	check(err)

	fmt.Println("--------")
	listNodes(clientset)

	fmt.Println("")
	listNamespaces(clientset)

	fmt.Println("")
	listPods(clientset)

	fmt.Println("")
	listDeployments(clientset)

	fmt.Println("")
	fmt.Println("--------")
	getPods(clientset, "docker-registry")
}

// check simply panics if there is an error.
func check(err error) {
	if err != nil {
		panic(err)
	}
}