Add purge flag to delete radius related namespace (radius-project#7847)

# Description

Add purge flag to delete radius related namespace, the purge flag should
be set explicitly(--purge=true).

## Type of change

- This pull request adds or changes features of Radius and has an
approved issue (issue link required).

issue link radius-project#7764

---------

Signed-off-by: lbzs <627062293@qq.com>
Co-authored-by: Ryan Nowak <nowakra@gmail.com>

pkg/cli/cmd/uninstall/kubernetes/kubernetes.go

@@ -18,6 +18,7 @@ package kubernetes
 
 import (
 	"context"
+	"github.com/radius-project/radius/pkg/cli/kubernetes"
 
 	"github.com/radius-project/radius/pkg/cli/cmd/commonflags"
 	"github.com/radius-project/radius/pkg/cli/framework"
@@ -48,23 +49,27 @@ rad uninstall kubernetes --kubecontext my-kubecontext`,
 	}
 
 	commonflags.AddKubeContextFlagVar(cmd, &runner.KubeContext)
+	cmd.Flags().BoolVar(&runner.Purge, "purge", false, "Delete all data stored by Radius.")
 
 	return cmd, runner
 }
 
 // Runner is the Runner implementation for the `rad uninstall kubernetes` command.
 type Runner struct {
-	Helm   helm.Interface
-	Output output.Interface
+	Helm       helm.Interface
+	Output     output.Interface
+	Kubernetes kubernetes.Interface
 
 	KubeContext string
+	Purge       bool
 }
 
 // NewRunner creates an instance of the runner for the `rad uninstall kubernetes` command.
 func NewRunner(factory framework.Factory) *Runner {
 	return &Runner{
-		Helm:   factory.GetHelmInterface(),
-		Output: factory.GetOutput(),
+		Helm:       factory.GetHelmInterface(),
+		Output:     factory.GetOutput(),
+		Kubernetes: factory.GetKubernetesInterface(),
 	}
 }
 
@@ -97,6 +102,14 @@ func (r *Runner) Run(ctx context.Context) error {
 		return err
 	}
 
+	if r.Purge {
+		r.Output.LogInfo("Deleting namespace %s", helm.RadiusSystemNamespace)
+		if err := r.Kubernetes.DeleteNamespace(r.KubeContext); err != nil {
+			return err
+		}
+		r.Output.LogInfo("Radius was fully uninstalled. Any existing data have been removed.")
+		return nil
+	}
 	r.Output.LogInfo("Radius was uninstalled successfully. Any existing data will be retained for future installations. Local configuration is also retained. Use the `rad workspace` command if updates are needed to your configuration.")
 	return nil
 }

pkg/cli/cmd/uninstall/kubernetes/kubernetes_test.go

@@ -18,6 +18,7 @@ package kubernetes
 
 import (
 	"context"
+	"github.com/radius-project/radius/pkg/cli/kubernetes"
 	"testing"
 
 	"github.com/radius-project/radius/pkg/cli/helm"
@@ -115,4 +116,47 @@ func Test_Run(t *testing.T) {
 		}
 		require.Equal(t, expectedWrites, outputMock.Writes)
 	})
+	t.Run("Success: Installed -> Uninstalled -> Purge)", func(t *testing.T) {
+		ctrl := gomock.NewController(t)
+		helmMock := helm.NewMockInterface(ctrl)
+		outputMock := &output.MockOutput{}
+		k8sMock := kubernetes.NewMockInterface(ctrl)
+
+		ctx := context.Background()
+		runner := &Runner{
+			Helm:       helmMock,
+			Output:     outputMock,
+			Kubernetes: k8sMock,
+
+			KubeContext: "test-context",
+			Purge:       true,
+		}
+
+		helmMock.EXPECT().CheckRadiusInstall("test-context").
+			Return(helm.InstallState{Installed: true, Version: "test-version"}, nil).
+			Times(1)
+
+		helmMock.EXPECT().UninstallRadius(ctx, "test-context").
+			Return(nil).
+			Times(1)
+
+		k8sMock.EXPECT().DeleteNamespace("test-context").Return(nil).Times(1)
+
+		err := runner.Run(ctx)
+		require.NoError(t, err)
+
+		expectedWrites := []any{
+			output.LogOutput{
+				Format: "Uninstalling Radius...",
+			},
+			output.LogOutput{
+				Format: "Deleting namespace %s",
+				Params: []any{helm.RadiusSystemNamespace},
+			},
+			output.LogOutput{
+				Format: "Radius was fully uninstalled. Any existing data have been removed.",
+			},
+		}
+		require.Equal(t, expectedWrites, outputMock.Writes)
+	})
 }

pkg/cli/kubernetes/kubernetes.go

@@ -20,9 +20,13 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"github.com/radius-project/radius/pkg/cli/helm"
+	"k8s.io/apimachinery/pkg/util/wait"
+	"time"
 
 	contourv1 "github.com/projectcontour/contour/apis/projectcontour/v1"
 	apiextv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	k8s_runtime "k8s.io/apimachinery/pkg/runtime"
 	applycorev1 "k8s.io/client-go/applyconfigurations/core/v1"
@@ -117,6 +121,30 @@ func EnsureNamespace(ctx context.Context, client k8s.Interface, namespace string
 	return nil
 }
 
+// deleteNamespace delete the specified namespace.
+func deleteNamespace(ctx context.Context, client k8s.Interface, namespace string) error {
+	if err := client.CoreV1().Namespaces().
+		Delete(ctx, namespace, metav1.DeleteOptions{}); err != nil {
+		return err
+	}
+
+	// Ensure the namespace is deleted. This will block until the namespace is no longer exist.
+	err := wait.PollUntilContextCancel(ctx, 2*time.Second, true, func(ctx context.Context) (done bool, err error) {
+		_, err = client.CoreV1().Namespaces().Get(ctx, namespace, metav1.GetOptions{})
+		if err != nil {
+			if apierrors.IsNotFound(err) {
+				return true, nil
+			}
+			return false, err
+		}
+		return false, nil
+	})
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 // NewCLIClientConfig creates new Kubernetes client config loading from local home directory with CLI options.
 //
 
@@ -160,6 +188,7 @@ func GetContextFromConfigFileIfExists(configFilePath, context string) (string, e
 //go:generate mockgen -typed -destination=./mock_kubernetes.go -package=kubernetes -self_package github.com/radius-project/radius/pkg/cli/kubernetes github.com/radius-project/radius/pkg/cli/kubernetes Interface
 type Interface interface {
 	GetKubeContext() (*api.Config, error)
+	DeleteNamespace(string) error
 }
 
 type Impl struct {
@@ -172,3 +201,14 @@ type Impl struct {
 func (i *Impl) GetKubeContext() (*api.Config, error) {
 	return kubeutil.LoadConfigFile("")
 }
+
+func (i *Impl) DeleteNamespace(kubeContext string) error {
+	clientSet, _, err := NewClientset(kubeContext)
+	if err != nil {
+		return err
+	}
+	if err := deleteNamespace(context.Background(), clientSet, helm.RadiusSystemNamespace); err != nil {
+		return err
+	}
+	return nil
+}

pkg/cli/kubernetes/kubernetes_test.go

@@ -25,6 +25,7 @@ import (
 	"github.com/radius-project/radius/test/k8sutil"
 	"github.com/stretchr/testify/require"
 	v1 "k8s.io/api/core/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	meta_v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	k8sfake "k8s.io/client-go/kubernetes/fake"
@@ -49,6 +50,19 @@ func TestEnsureNamespace(t *testing.T) {
 	require.NoError(t, err)
 }
 
+func TestDeleteNamespace(t *testing.T) {
+	namespace := "radius-test"
+	f := k8sfake.NewSimpleClientset(&v1.Namespace{ObjectMeta: meta_v1.ObjectMeta{Name: namespace}})
+
+	ctx := context.Background()
+	_, err := f.CoreV1().Namespaces().Get(ctx, namespace, meta_v1.GetOptions{})
+	require.NoError(t, err)
+	err = deleteNamespace(ctx, f, namespace)
+	require.NoError(t, err)
+	_, err = f.CoreV1().Namespaces().Get(ctx, namespace, meta_v1.GetOptions{})
+	require.True(t, apierrors.IsNotFound(err), "expected not found error but got %v", err)
+}
+
 func TestGetContextFromConfigFileIfExists(t *testing.T) {
 	configFile, err := os.CreateTemp("", "")
 	require.NoError(t, err)