feat: add optional boolean '--wait' flag to 'uninstall' command.

If set, 'uninstall' command will wait until all the resources are deleted before returning.
It will wait for as long as --timeout

closes #2378

Signed-off-by: Mike Ng <ming@redhat.com>

cmd/helm/testdata/output/uninstall-wait.txt

@@ -0,0 +1 @@
+release "aeneas" uninstalled

cmd/helm/uninstall.go

@@ -71,6 +71,7 @@ func newUninstallCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 	f.BoolVar(&client.DryRun, "dry-run", false, "simulate a uninstall")
 	f.BoolVar(&client.DisableHooks, "no-hooks", false, "prevent hooks from running during uninstallation")
 	f.BoolVar(&client.KeepHistory, "keep-history", false, "remove all associated resources and mark the release as deleted, but retain the release history")
+	f.BoolVar(&client.Wait, "wait", false, "if set, will wait until all the resources are deleted before returning. It will wait for as long as --timeout")
 	f.DurationVar(&client.Timeout, "timeout", 300*time.Second, "time to wait for any individual Kubernetes operation (like Jobs for hooks)")
 	f.StringVar(&client.Description, "description", "", "add a custom description")
 

cmd/helm/uninstall_test.go

@@ -57,6 +57,12 @@ func TestUninstall(t *testing.T) {
 			golden: "output/uninstall-keep-history.txt",
 			rels:   []*release.Release{release.Mock(&release.MockReleaseOptions{Name: "aeneas"})},
 		},
+		{
+			name:   "wait",
+			cmd:    "uninstall aeneas --wait",
+			golden: "output/uninstall-wait.txt",
+			rels:   []*release.Release{release.Mock(&release.MockReleaseOptions{Name: "aeneas"})},
+		},
 		{
 			name:      "uninstall without release",
 			cmd:       "uninstall",

pkg/action/uninstall.go

@@ -23,6 +23,7 @@ import (
 	"github.com/pkg/errors"
 
 	"helm.sh/helm/v3/pkg/chartutil"
+	"helm.sh/helm/v3/pkg/kube"
 	"helm.sh/helm/v3/pkg/release"
 	"helm.sh/helm/v3/pkg/releaseutil"
 	helmtime "helm.sh/helm/v3/pkg/time"
@@ -37,6 +38,7 @@ type Uninstall struct {
 	DisableHooks bool
 	DryRun       bool
 	KeepHistory  bool
+	Wait         bool
 	Timeout      time.Duration
 	Description  string
 }
@@ -110,13 +112,19 @@ func (u *Uninstall) Run(name string) (*release.UninstallReleaseResponse, error)
 		u.cfg.Log("uninstall: Failed to store updated release: %s", err)
 	}
 
-	kept, errs := u.deleteRelease(rel)
+	deletedResources, kept, errs := u.deleteRelease(rel)
 
 	if kept != "" {
 		kept = "These resources were kept due to the resource policy:\n" + kept
 	}
 	res.Info = kept
 
+	if u.Wait {
+		if err := u.cfg.KubeClient.WaitForDelete(deletedResources, u.Timeout); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
 	if !u.DisableHooks {
 		if err := u.cfg.execHook(rel, release.HookPostDelete, u.Timeout); err != nil {
 			errs = append(errs, err)
@@ -172,12 +180,12 @@ func joinErrors(errs []error) string {
 	return strings.Join(es, "; ")
 }
 
-// deleteRelease deletes the release and returns manifests that were kept in the deletion process
+// deleteRelease deletes the release and returns list of delete resources and manifests that were kept in the deletion process
-func (u *Uninstall) deleteRelease(rel *release.Release) (string, []error) {
+func (u *Uninstall) deleteRelease(rel *release.Release) (kube.ResourceList, string, []error) {
 	var errs []error
 	caps, err := u.cfg.getCapabilities()
 	if err != nil {
-		return rel.Manifest, []error{errors.Wrap(err, "could not get apiVersions from Kubernetes")}
+		return nil, rel.Manifest, []error{errors.Wrap(err, "could not get apiVersions from Kubernetes")}
 	}
 
 	manifests := releaseutil.SplitManifests(rel.Manifest)
@@ -187,7 +195,7 @@ func (u *Uninstall) deleteRelease(rel *release.Release) (string, []error) {
 		// FIXME: One way to delete at this point would be to try a label-based
 		// deletion. The problem with this is that we could get a false positive
 		// and delete something that was not legitimately part of this release.
-		return rel.Manifest, []error{errors.Wrap(err, "corrupted release record. You must manually delete the resources")}
+		return nil, rel.Manifest, []error{errors.Wrap(err, "corrupted release record. You must manually delete the resources")}
 	}
 
 	filesToKeep, filesToDelete := filterManifestsToKeep(files)
@@ -203,10 +211,10 @@ func (u *Uninstall) deleteRelease(rel *release.Release) (string, []error) {
 
 	resources, err := u.cfg.KubeClient.Build(strings.NewReader(builder.String()), false)
 	if err != nil {
-		return "", []error{errors.Wrap(err, "unable to build kubernetes objects for delete")}
+		return nil, "", []error{errors.Wrap(err, "unable to build kubernetes objects for delete")}
 	}
 	if len(resources) > 0 {
 		_, errs = u.cfg.KubeClient.Delete(resources)
 	}
-	return kept, errs
+	return resources, kept, errs
 }

pkg/action/uninstall_test.go

@@ -17,9 +17,13 @@ limitations under the License.
 package action
 
 import (
+	"fmt"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+
+	kubefake "helm.sh/helm/v3/pkg/kube/fake"
+	"helm.sh/helm/v3/pkg/release"
 )
 
 func uninstallAction(t *testing.T) *Uninstall {
@@ -60,3 +64,34 @@ func TestUninstallRelease_deleteRelease(t *testing.T) {
 `
 	is.Contains(res.Info, expected)
 }
+
+func TestUninstallRelease_Wait(t *testing.T) {
+	is := assert.New(t)
+
+	unAction := uninstallAction(t)
+	unAction.DisableHooks = true
+	unAction.DryRun = false
+	unAction.Wait = true
+
+	rel := releaseStub()
+	rel.Name = "come-fail-away"
+	rel.Manifest = `{
+		"apiVersion": "v1",
+		"kind": "Secret",
+		"metadata": {
+		  "name": "secret"
+		},
+		"type": "Opaque",
+		"data": {
+		  "password": "password"
+		}
+	}`
+	unAction.cfg.Releases.Create(rel)
+	failer := unAction.cfg.KubeClient.(*kubefake.FailingKubeClient)
+	failer.WaitError = fmt.Errorf("U timed out")
+	unAction.cfg.KubeClient = failer
+	res, err := unAction.Run(rel.Name)
+	is.Error(err)
+	is.Contains(err.Error(), "U timed out")
+	is.Equal(res.Release.Info.Status, release.StatusUninstalled)
+}

pkg/kube/client.go

@@ -162,6 +162,15 @@ func (c *Client) WaitWithJobs(resources ResourceList, timeout time.Duration) err
 	return w.waitForResources(resources)
 }
 
+// Wait up to the given timeout for the specified resources to be deleted
+func (c *Client) WaitForDelete(resources ResourceList, timeout time.Duration) error {
+	w := waiter{
+		log:     c.Log,
+		timeout: timeout,
+	}
+	return w.waitForDeletedResources(resources)
+}
+
 func (c *Client) namespace() string {
 	if c.Namespace != "" {
 		return c.Namespace

pkg/kube/fake/fake.go

@@ -63,7 +63,15 @@ func (f *FailingKubeClient) WaitWithJobs(resources kube.ResourceList, d time.Dur
 	if f.WaitError != nil {
 		return f.WaitError
 	}
-	return f.PrintingKubeClient.Wait(resources, d)
+	return f.PrintingKubeClient.WaitWithJobs(resources, d)
+}
+
+// WaitForDelete returns the configured error if set or prints
+func (f *FailingKubeClient) WaitForDelete(resources kube.ResourceList, d time.Duration) error {
+	if f.WaitError != nil {
+		return f.WaitError
+	}
+	return f.PrintingKubeClient.WaitForDelete(resources, d)
 }
 
 // Delete returns the configured error if set or prints

pkg/kube/fake/printer.go

@@ -57,6 +57,11 @@ func (p *PrintingKubeClient) WaitWithJobs(resources kube.ResourceList, _ time.Du
 	return err
 }
 
+func (p *PrintingKubeClient) WaitForDelete(resources kube.ResourceList, _ time.Duration) error {
+	_, err := io.Copy(p.Out, bufferize(resources))
+	return err
+}
+
 // Delete implements KubeClient delete.
 //
 // It only prints out the content to be deleted.

pkg/kube/interface.go

@@ -36,6 +36,8 @@ type Interface interface {
 	// WaitWithJobs wait up to the given timeout for the specified resources to be ready, including jobs.
 	WaitWithJobs(resources ResourceList, timeout time.Duration) error
 
+	WaitForDelete(resources ResourceList, timeout time.Duration) error
+
 	// Delete destroys one or more resources.
 	Delete(resources ResourceList) (*Result, []error)
 

pkg/kube/wait.go

@@ -28,6 +28,7 @@ import (
 	batchv1 "k8s.io/api/batch/v1"
 	corev1 "k8s.io/api/core/v1"
 	extensionsv1beta1 "k8s.io/api/extensions/v1beta1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/runtime"
@@ -60,6 +61,24 @@ func (w *waiter) waitForResources(created ResourceList) error {
 	}, ctx.Done())
 }
 
+// waitForDeletedResources polls to check if all the resources are deleted or a timeout is reached
+func (w *waiter) waitForDeletedResources(deleted ResourceList) error {
+	w.log("beginning wait for %d resources to be deleted with timeout of %v", len(deleted), w.timeout)
+
+	ctx, cancel := context.WithTimeout(context.Background(), w.timeout)
+	defer cancel()
+
+	return wait.PollImmediateUntil(2*time.Second, func() (bool, error) {
+		for _, v := range deleted {
+			err := v.Get()
+			if err == nil || !apierrors.IsNotFound(err) {
+				return false, err
+			}
+		}
+		return true, nil
+	}, ctx.Done())
+}
+
 // SelectorsForObject returns the pod label selector for a given object
 //
 // Modified version of https://github.com/kubernetes/kubernetes/blob/v1.14.1/pkg/kubectl/polymorphichelpers/helpers.go#L84