feat(helm): add '--replace' option to 'upgrade' command

Fixes issue #5595

Signed-off-by: Matt Morrissette <yinzara@gmail.com>

cmd/helm/testdata/output/upgrade-with-bad-or-missing-existing-release.txt

@@ -0,0 +1 @@
+Error: UPGRADE FAILED: "funny-bunny" has no deployed releases

cmd/helm/upgrade.go

@@ -88,7 +88,6 @@ func newUpgradeCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 			if err != nil {
 				return err
 			}
-
 			if client.Install {
 				// If a release does not exist, install it. If another error occurs during
 				// the check, ignore the error and continue with the upgrade.
@@ -176,6 +175,7 @@ func newUpgradeCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 	f.BoolVar(&client.CleanupOnFail, "cleanup-on-fail", false, "allow deletion of new resources created in this upgrade when upgrade fails")
 	f.BoolVar(&client.SubNotes, "render-subchart-notes", false, "if set, render subchart notes along with the parent")
 	f.StringVar(&client.Description, "description", "", "add a custom description")
+	f.BoolVar(&client.Replace, "replace", false, "if no deployed version of the release is available, replace an uninstalled, pending install, or failed release which remains in the history. If no prior failed, uninstalled, pending install or deployed release is available, --replace will not install a new release unless --install is also specified. This is unsafe in production")
 	addChartPathOptionsFlags(f, &client.ChartPathOptions)
 	addValueOptionsFlags(f, valueOpts)
 	bindOutputFlag(cmd, &outfmt)

cmd/helm/upgrade_test.go

@@ -79,6 +79,10 @@ func TestUpgradeCmd(t *testing.T) {
 	missingDepsPath := "testdata/testcharts/chart-missing-deps"
 	badDepsPath := "testdata/testcharts/chart-bad-requirements"
 
+	relWithStatusMock := func(n string, v int, ch *chart.Chart, status release.Status) *release.Release {
+		return release.Mock(&release.MockReleaseOptions{Name: n, Version: v, Chart: ch, Status: status})
+	}
+
 	relMock := func(n string, v int, ch *chart.Chart) *release.Release {
 		return release.Mock(&release.MockReleaseOptions{Name: n, Version: v, Chart: ch})
 	}
@@ -138,6 +142,25 @@ func TestUpgradeCmd(t *testing.T) {
 			golden:    "output/upgrade-with-bad-dependencies.txt",
 			wantError: true,
 		},
+		{
+			name:      "upgrade a failed release",
+			cmd:       fmt.Sprintf("upgrade funny-bunny '%s'", chartPath),
+			golden:    "output/upgrade-with-bad-or-missing-existing-release.txt",
+			rels:      []*release.Release{relWithStatusMock("funny-bunny", 1, ch, release.StatusFailed)},
+			wantError: true,
+		},
+		{
+			name:      "upgrade a non-existant release using 'upgrade --replace'",
+			cmd:       fmt.Sprintf("upgrade funny-bunny --replace '%s'", chartPath),
+			golden:    "output/upgrade-with-bad-or-missing-existing-release.txt",
+			wantError: true,
+		},
+		{
+			name:   "upgrade a failed release using 'upgrade --replace'",
+			cmd:    fmt.Sprintf("upgrade funny-bunny --replace '%s'", chartPath),
+			golden: "output/upgrade.txt",
+			rels:   []*release.Release{relWithStatusMock("funny-bunny", 2, ch, release.StatusFailed)},
+		},
 	}
 	runTestCmd(t, tests)
 }

pkg/action/upgrade.go

@@ -62,6 +62,7 @@ type Upgrade struct {
 	Description              string
 	PostRenderer             postrender.PostRenderer
 	DisableOpenAPIValidation bool
+	Replace                  bool
 }
 
 // NewUpgrade creates a new Upgrade object with the given configuration.
@@ -122,12 +123,33 @@ func (u *Upgrade) prepareUpgrade(name string, chart *chart.Chart, vals map[strin
 		return nil, nil, errMissingChart
 	}
 
-	// finds the deployed release with the given name
-	currentRelease, err := u.cfg.Releases.Deployed(name)
+	// finds the last non-deleted release with the given name
+	lastRelease, err := u.cfg.Releases.Last(name)
 	if err != nil {
+		// to keep existing behavior of returning the "%q has no deployed releases" error when an existing release does not exist
+		if strings.Contains(err.Error(), "no revision for release") {
+			return nil, nil, errors.Errorf("%q has no deployed releases", name)
+		}
 		return nil, nil, err
 	}
 
+	var currentRelease *release.Release
+	if lastRelease.Info.Status == release.StatusDeployed {
+		// no need to retrieve the last deployed release from storage as the last release is deployed
+		currentRelease = lastRelease
+	} else {
+		// finds the deployed release with the given name
+		currentRelease, err = u.cfg.Releases.Deployed(name)
+		if err != nil {
+			if u.Replace && strings.Contains(err.Error(), "has no deployed releases") &&
+				(lastRelease.Info.Status == release.StatusFailed || lastRelease.Info.Status == release.StatusPendingInstall || lastRelease.Info.Status == release.StatusUninstalled) {
+				currentRelease = lastRelease
+			} else {
+				return nil, nil, err
+			}
+		}
+	}
+
 	// determine if values will be reused
 	vals, err = u.reuseValues(chart, currentRelease, vals)
 	if err != nil {
@@ -138,12 +160,6 @@ func (u *Upgrade) prepareUpgrade(name string, chart *chart.Chart, vals map[strin
 		return nil, nil, err
 	}
 
-	// finds the non-deleted release with the given name
-	lastRelease, err := u.cfg.Releases.Last(name)
-	if err != nil {
-		return nil, nil, err
-	}
-
 	// Increment revision count. This is passed to templates, and also stored on
 	// the release object.
 	revision := lastRelease.Version + 1