main.go

package main

import (
	"context"
	"flag"
	"fmt"
	"os"
	"path/filepath"
	"strconv"
	"strings"

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

	_ "k8s.io/client-go/plugin/pkg/client/auth"
)

func isNodeReady(node v1.Node) bool {
	for _, condition := range node.Status.Conditions {
		if condition.Type == "Ready" {
			return condition.Status == "True"
		}
	}
	return false
}

func main() {
	var kubeconfig *string
	ctx := context.Background()

	if kubeconfigEnvvar := os.Getenv("KUBECONFIG"); kubeconfigEnvvar != "" {
		kubeconfigTokenized := strings.Split(kubeconfigEnvvar, ";")
		kubeconfig = flag.String("kubeconfig", kubeconfigTokenized[0], "absolute path to the kubeconfig file")
	} else 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())
	}

	pods, err := clientset.CoreV1().Pods("").List(ctx, metav1.ListOptions{})
	if err != nil {
		panic(err.Error())
	}
	fmt.Printf("Number of pods registered: %d\n", len(pods.Items))
	nonReadyPods := 0
	for index, pod := range pods.Items {
		if pod.Status.Phase != v1.PodRunning {
			fmt.Printf("tmp")
			fmt.Printf(strconv.Itoa(index))
			nonReadyPods++
		}
	}
	fmt.Printf("Number of non-running pods: %d\n", nonReadyPods)

	deploys, err := clientset.AppsV1().Deployments("").List(ctx, metav1.ListOptions{})
	if err != nil {
		panic(err.Error())
	}
	fmt.Printf("Number of deployments registered: %d\n", len(deploys.Items))
	nonReadyDeploys := 0
	for _, deploy := range deploys.Items {
		if deploy.Status.UnavailableReplicas > 0 {
			fmt.Printf("Not Ready Deployment: %s", deploy.GetName())
			nonReadyDeploys++
		}
	}
	fmt.Printf("Number of incomplete deployments: %d\n", nonReadyDeploys)

	// daemonsets
	daemonsets, err := clientset.AppsV1().DaemonSets("").List(ctx, metav1.ListOptions{})
	if err != nil {
		panic(err.Error())
	}
	fmt.Printf("Number of daemonsets registered: %d\n", len(daemonsets.Items))
	nonReadyDaemonsets := 0
	for _, daemonset := range daemonsets.Items {
		if daemonset.Status.NumberUnavailable > 0 {
			fmt.Printf("Not Ready DaemonSet: %s", daemonset.GetName())
			nonReadyDaemonsets++
		}
	}
	fmt.Printf("Number of incomplete daemonsets: %d\n", nonReadyDaemonsets)

	nodes, err := clientset.CoreV1().Nodes().List(ctx, metav1.ListOptions{})
	if err != nil {
		panic(err.Error())
	}
	fmt.Printf("Number of nodes registered: %d\n", len(nodes.Items))
	nonReadyNodes := 0
	for index, node := range nodes.Items {
		if !isNodeReady(node) {
			fmt.Printf("tmp")
			fmt.Printf("Not Ready Node: %s", node.GetName())
			fmt.Printf(strconv.Itoa(index))
			nonReadyNodes++
		}
	}
	fmt.Printf("Number of incomplete nodes: %d\n", nonReadyNodes)

	// Examples for error handling:
	// - Use helper functions like e.g. errors.IsNotFound()
	// - And/or cast to StatusError and use its properties like e.g. ErrStatus.Message
	namespace := "default"
	pod := "example-xxxxx"
	_, err = clientset.CoreV1().Pods(namespace).Get(ctx, pod, metav1.GetOptions{})
	if errors.IsNotFound(err) {
		fmt.Printf("Pod %s in namespace %s not found\n", pod, namespace)
	} else if statusError, isStatus := err.(*errors.StatusError); isStatus {
		fmt.Printf("Error getting pod %s in namespace %s: %v\n", pod, namespace, statusError.ErrStatus.Message)
	} else if err != nil {
		panic(err.Error())
	} else {
		fmt.Printf("Found pod %s in namespace %s\n", pod, namespace)
	}

}

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