nginx pod checker

nginxpodchecker.go

package main

import (
	"fmt"
	"os"
	"time"

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

var nginxPod = []byte(`apiVersion: v1
kind: Pod
metadata:
  name: nginx
  labels:
    name: nginx
spec:
  containers:
  - name: nginx
    image: nginx
    ports:
    - containerPort: 80
`)

var curlPod = &v1.Pod{
	ObjectMeta: metav1.ObjectMeta{
		Name:      "curl-pod",
		Namespace: "default",
	},
	Spec: v1.PodSpec{
		Containers: []v1.Container{
			{
				Name:  "curl-container",
				Image: "byrnedo/alpine-curl", // TODO(yifan): Host this image under quay.io/coreos/
			},
		},
		RestartPolicy: v1.RestartPolicyNever,
	},
}

func main() {
	kubeconfig := os.Getenv("KUBECONFIG")
	if kubeconfig == "" {
		panic("no kubeconfig")
	}

	config, err := clientcmd.BuildConfigFromFlags("", kubeconfig)
	if err != nil {
		panic(err)
	}

	client, err := kubernetes.NewForConfig(config)
	if err != nil {
		panic(err)
	}

	obj, _, err := api.Codecs.UniversalDecoder().Decode(nginxPod, nil, &v1.Pod{})
	if err != nil {
		panic(err)
	}

	pod, ok := obj.(*v1.Pod)
	if !ok {
		panic("not a pod")
	}

	// 1. Run the nginx pod.
	_, err = client.CoreV1().Pods("default").Create(pod)
	if err != nil {
		panic(err)
	}

	time.Sleep(time.Second * 5)

	// 2. Get the nginx pod IP.
	running := false
	var p *v1.Pod
	for i := 0; i < 10; i++ {
		p, err = client.CoreV1().Pods("default").Get("nginx", metav1.GetOptions{})
		if err == nil && p.Status.Phase == v1.PodRunning {
			running = true
			break
		}
		time.Sleep(time.Second)
	}

	if !running {
		panic("time out waiting nginx running")
	}

	fmt.Println("pod ip", p.Status.PodIP)

	// 3. Create a curl pod that curls the nginx pod IP.
	curlPod.Spec.Containers[0].Command = []string{"curl", "--fail", p.Status.PodIP}

	_, err = client.CoreV1().Pods("default").Create(curlPod)
	if err != nil {
		panic(err)
	}

	time.Sleep(time.Second * 5)

	succeeded := false
	for i := 0; i < 10; i++ {
		p, err = client.CoreV1().Pods("default").Get("curl-pod", metav1.GetOptions{})
		if err == nil && p.Status.Phase == v1.PodSucceeded {
			succeeded = true
			break
		}
		time.Sleep(time.Second)
	}

	if !succeeded {
		panic("not succeeded")
	}

	fmt.Println("PASS")
}