export nodes info into an archive

Signed-off-by: Chandan-DK <chandandk468@gmail.com>

cmd/cli/kubectl-kyverno/sysdump/sysdump.go

@@ -1,17 +1,122 @@
 package sysdump
 
 import (
+	"bytes"
+	"context"
+	"fmt"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+	"time"
+
+	kyverno "github.com/kyverno/kyverno/pkg/client/clientset/versioned"
+	kyvernoscheme "github.com/kyverno/kyverno/pkg/client/clientset/versioned/scheme"
+	"github.com/mholt/archiver"
 	"github.com/spf13/cobra"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/cli-runtime/pkg/printers"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/kubernetes/scheme"
+	"k8s.io/client-go/tools/clientcmd"
+	"k8s.io/client-go/util/homedir"
 )
 
+type client struct {
+	kubernetesClientSet *kubernetes.Clientset
+	kyvernoClientSet    *kyverno.Clientset
+}
+
 func Command() *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "sysdump",
 		Short: "Collect and package information for troubleshooting",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			homeDir := homedir.HomeDir()
+
+			clients, err := initializeClients(homeDir)
+			if err != nil {
+				return err
+			}
 
-		Run: func(cmd *cobra.Command, args []string) {
+			dir, err := os.MkdirTemp("", "kyverno-sysdump")
+			if err != nil {
+				return err
+			}
 
+			if err := exportNodesInfo(clients, dir); err != nil {
+				return err
+			}
+
+			if err := createArchive(dir, homeDir); err != nil {
+				return err
+			}
+
+			return nil
 		},
 	}
 	return cmd
 }
+
+func initializeClients(homeDir string) (*client, error) {
+	var clients client
+
+	kubeconfig := filepath.Join(homeDir, ".kube", "config")
+
+	config, err := clientcmd.BuildConfigFromFlags("", kubeconfig)
+	if err != nil {
+		return nil, fmt.Errorf("failed to load kubeconfig file: %v", err)
+	}
+
+	clients.kubernetesClientSet, err = kubernetes.NewForConfig(config)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create kubernetes clientset: %v", err)
+	}
+	clients.kyvernoClientSet, err = kyverno.NewForConfig(config)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create kyverno clientset: %v", err)
+	}
+	_ = kyvernoscheme.AddToScheme(scheme.Scheme)
+
+	return &clients, nil
+}
+
+// Create archive at home directory
+func createArchive(source, archiveDestination string) error {
+	sysdumpFile := archiveDestination + "/" + "kyverno-sysdump-" + strings.Replace(time.Now().Format(time.UnixDate), ":", "_", -1) + ".zip"
+	if err := archiver.Archive([]string{source}, sysdumpFile); err != nil {
+		return fmt.Errorf("failed to create sysdump zip file: %v", err)
+	}
+	fmt.Printf("Sysdump zip file created at %s", archiveDestination)
+	return nil
+}
+
+func exportNodesInfo(clients *client, destination string) error {
+	n, err := clients.kubernetesClientSet.CoreV1().Nodes().List(context.Background(), metav1.ListOptions{})
+	if err != nil {
+		return fmt.Errorf("failed to get NodeList: %v", err)
+	}
+
+	if err := writeYaml(path.Join(destination, "nodes-info.yaml"), n); err != nil {
+		return err
+	}
+	return nil
+}
+
+func writeToFile(p, v string) error {
+	return os.WriteFile(p, []byte(v), 0600)
+}
+
+func writeYaml(p string, o runtime.Object) error {
+	var j printers.YAMLPrinter
+	w, err := printers.NewTypeSetter(scheme.Scheme).WrapToPrinter(&j, nil)
+	if err != nil {
+		return fmt.Errorf("failed to wrap to printer: %v", err)
+	}
+	var b bytes.Buffer
+	if err := w.PrintObj(o, &b); err != nil {
+		return fmt.Errorf("failed to print %v to YAML: %v", o, err)
+	}
+	return writeToFile(p, b.String())
+}