Drasi Uninstall command

cli/cmd/root.go

@@ -15,6 +15,7 @@ func init() {
 		NewListCommand(),
 		NewWaitCommand(),
 		NewNamespaceCommand(),
+		NewUninstallCommand(),
 	)
 
 	RootCommand.PersistentFlags().StringP("namespace", "n", "drasi-system", "Kubernetes namespace to install Drasi into")

cli/cmd/uninstall.go

@@ -0,0 +1,74 @@
+package cmd
+
+import (
+	"fmt"
+	"log"
+	"strings"
+
+	"drasi.io/cli/service"
+	"github.com/spf13/cobra"
+)
+
+func NewUninstallCommand() *cobra.Command {
+	var uninstallCommand = &cobra.Command{
+		Use:   "uninstall ",
+		Short: "Uninstall Drasi",
+		Long:  `Uninstall Drasi from the current namespace`,
+		Args:  cobra.MinimumNArgs(0),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			cfg := readConfig()
+			var err error
+			var currentNamespace string
+			if currentNamespace, err = cmd.Flags().GetString("namespace"); err != nil {
+				return err
+			}
+			if !cmd.Flags().Changed("namespace") {
+				currentNamespace = cfg.DrasiNamespace
+			}
+
+			fmt.Println("Uninstalling Drasi")
+			fmt.Println("Deleting namespace: ", currentNamespace)
+
+			// Ask for confirmation if the user didn't pass the -y flag
+			if !cmd.Flags().Changed("yes") {
+				fmt.Printf("Are you sure you want to uninstall Drasi from the namespace %s? (yes/no): ", currentNamespace)
+				if !askForConfirmation(currentNamespace) {
+					fmt.Println("Uninstall cancelled")
+					return nil
+				}
+			}
+
+			err = service.UninstallDrasi(currentNamespace)
+			if err != nil {
+				return err
+			}
+
+			fmt.Println("Drasi uninstalled successfully")
+
+			return nil
+		},
+	}
+
+	uninstallCommand.Flags().BoolP("yes", "y", false, "uninstall -y")
+
+	return uninstallCommand
+}
+
+func askForConfirmation(namespace string) bool {
+	var response string
+
+	_, err := fmt.Scanln(&response)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	switch strings.ToLower(response) {
+	case "y", "yes":
+		return true
+	case "n", "no":
+		return false
+	default:
+		fmt.Println("I'm sorry but I didn't get what you meant, please type (y)es or (n)o and then press enter:")
+		return askForConfirmation(namespace)
+	}
+}

cli/service/uninstaller.go

@@ -0,0 +1,56 @@
+package service
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/tools/clientcmd"
+)
+
+func UninstallDrasi(namespace string) error {
+	configLoadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
+	configOverrides := &clientcmd.ConfigOverrides{}
+
+	config := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(configLoadingRules, configOverrides)
+
+	restConfig, err := config.ClientConfig()
+
+	if err != nil {
+		return err
+	}
+
+	clientset, err := kubernetes.NewForConfig(restConfig)
+	if err != nil {
+		return err
+	}
+
+	err = clientset.CoreV1().Namespaces().Delete(context.TODO(), namespace, metav1.DeleteOptions{})
+	if err != nil {
+		return err
+	}
+
+	// Pods are not deleted immediately; instead, they will remain in a Terminating state for a while
+	// Need to verify that all resources have been deleted; if not, wait for them to be deleted
+	nsDeleted := false
+	for !nsDeleted {
+		list, err := clientset.CoreV1().Namespaces().List(context.TODO(), metav1.ListOptions{})
+		if err != nil {
+			return err
+		}
+		for _, ns := range list.Items {
+			// check if the namespace is still there
+			if ns.Name == namespace {
+				fmt.Println("Namespace is still present. Waiting for it to be deleted")
+				// wait for 10 seconds
+				time.Sleep(10 * time.Second)
+			} else {
+				nsDeleted = true
+			}
+		}
+	}
+
+	return nil
+}