helm init --upgrade will downgrade (#2805)

* Don't downgrade tiller with helm init --upgrade unless --force-upgrade is specified
Fix tests after merging master

* Reformatting with gofmt

cmd/helm/init.go

@@ -76,6 +76,7 @@ type initCmd struct {
 	upgrade        bool
 	namespace      string
 	dryRun         bool
+	forceUpgrade   bool
 	skipRefresh    bool
 	out            io.Writer
 	home           helmpath.Home
@@ -106,6 +107,7 @@ func newInitCmd(out io.Writer) *cobra.Command {
 	f.StringVarP(&i.image, "tiller-image", "i", "", "override Tiller image")
 	f.BoolVar(&i.canary, "canary-image", false, "use the canary Tiller image")
 	f.BoolVar(&i.upgrade, "upgrade", false, "upgrade if Tiller is already installed")
+	f.BoolVar(&i.forceUpgrade, "force-upgrade", false, "force upgrade of Tiller to the current helm version")
 	f.BoolVarP(&i.clientOnly, "client-only", "c", false, "if set does not install Tiller")
 	f.BoolVar(&i.dryRun, "dry-run", false, "do not install local or remote")
 	f.BoolVar(&i.skipRefresh, "skip-refresh", false, "do not refresh (download) the local repository cache")
@@ -164,6 +166,7 @@ func (i *initCmd) run() error {
 	i.opts.Namespace = i.namespace
 	i.opts.UseCanary = i.canary
 	i.opts.ImageSpec = i.image
+	i.opts.ForceUpgrade = i.forceUpgrade
 	i.opts.ServiceAccount = i.serviceAccount
 	i.opts.MaxHistory = i.maxHistory
 

cmd/helm/installer/install.go

@@ -17,10 +17,12 @@ limitations under the License.
 package installer // import "k8s.io/helm/cmd/helm/installer"
 
 import (
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"strings"
 
+	"github.com/Masterminds/semver"
 	"github.com/ghodss/yaml"
 	"k8s.io/api/core/v1"
 	"k8s.io/api/extensions/v1beta1"
@@ -30,6 +32,7 @@ import (
 	"k8s.io/client-go/kubernetes"
 	corev1 "k8s.io/client-go/kubernetes/typed/core/v1"
 	extensionsclient "k8s.io/client-go/kubernetes/typed/extensions/v1beta1"
+	"k8s.io/helm/pkg/version"
 
 	"k8s.io/helm/pkg/chartutil"
 )
@@ -60,6 +63,10 @@ func Upgrade(client kubernetes.Interface, opts *Options) error {
 	if err != nil {
 		return err
 	}
+	existingImage := obj.Spec.Template.Spec.Containers[0].Image
+	if !isNewerVersion(existingImage) && !opts.ForceUpgrade {
+		return errors.New("current Tiller version is newer, use --force-upgrade to downgrade")
+	}
 	obj.Spec.Template.Spec.Containers[0].Image = opts.selectImage()
 	obj.Spec.Template.Spec.Containers[0].ImagePullPolicy = opts.pullPolicy()
 	obj.Spec.Template.Spec.ServiceAccountName = opts.ServiceAccount
@@ -75,6 +82,17 @@ func Upgrade(client kubernetes.Interface, opts *Options) error {
 	return err
 }
 
+// isNewerVersion returns whether the current version is newer than the give image's version
+func isNewerVersion(image string) bool {
+	split := strings.Split(image, ":")
+	if len(split) < 2 {
+		// If we don't know the version, we consider the current version newer
+		return true
+	}
+	imageVersion := split[1]
+	return semver.MustParse(version.Version).GreaterThan(semver.MustParse(imageVersion))
+}
+
 // createDeployment creates the Tiller Deployment resource.
 func createDeployment(client extensionsclient.DeploymentsGetter, opts *Options) error {
 	obj, err := deployment(opts)

cmd/helm/installer/install_test.go

@@ -337,7 +337,7 @@ func TestUpgrade(t *testing.T) {
 	serviceAccount := "newServiceAccount"
 	existingDeployment, _ := deployment(&Options{
 		Namespace:      v1.NamespaceDefault,
-		ImageSpec:      "imageToReplace",
+		ImageSpec:      "imageToReplace:v1.0.0",
 		ServiceAccount: "serviceAccountToReplace",
 		UseCanary:      false,
 	})
@@ -416,6 +416,66 @@ func TestUpgrade_serviceNotFound(t *testing.T) {
 	}
 }
 
+func TestUgrade_newerVersion(t *testing.T) {
+	image := "gcr.io/kubernetes-helm/tiller:v2.0.0"
+	serviceAccount := "newServiceAccount"
+	existingDeployment, _ := deployment(&Options{
+		Namespace:      v1.NamespaceDefault,
+		ImageSpec:      "imageToReplace:v100.5.0",
+		ServiceAccount: "serviceAccountToReplace",
+		UseCanary:      false,
+	})
+	existingService := service(v1.NamespaceDefault)
+
+	fc := &fake.Clientset{}
+	fc.AddReactor("get", "deployments", func(action testcore.Action) (bool, runtime.Object, error) {
+		return true, existingDeployment, nil
+	})
+	fc.AddReactor("update", "deployments", func(action testcore.Action) (bool, runtime.Object, error) {
+		obj := action.(testcore.UpdateAction).GetObject().(*v1beta1.Deployment)
+		i := obj.Spec.Template.Spec.Containers[0].Image
+		if i != image {
+			t.Errorf("expected image = '%s', got '%s'", image, i)
+		}
+		sa := obj.Spec.Template.Spec.ServiceAccountName
+		if sa != serviceAccount {
+			t.Errorf("expected serviceAccountName = '%s', got '%s'", serviceAccount, sa)
+		}
+		return true, obj, nil
+	})
+	fc.AddReactor("get", "services", func(action testcore.Action) (bool, runtime.Object, error) {
+		return true, existingService, nil
+	})
+
+	opts := &Options{
+		Namespace:      v1.NamespaceDefault,
+		ImageSpec:      image,
+		ServiceAccount: serviceAccount,
+		ForceUpgrade:   false,
+	}
+	if err := Upgrade(fc, opts); err == nil {
+		t.Errorf("Expected error because the deployed version is newer")
+	}
+
+	if actions := fc.Actions(); len(actions) != 1 {
+		t.Errorf("unexpected actions: %v, expected 1 action got %d", actions, len(actions))
+	}
+
+	opts = &Options{
+		Namespace:      v1.NamespaceDefault,
+		ImageSpec:      image,
+		ServiceAccount: serviceAccount,
+		ForceUpgrade:   true,
+	}
+	if err := Upgrade(fc, opts); err != nil {
+		t.Errorf("unexpected error: %#+v", err)
+	}
+
+	if actions := fc.Actions(); len(actions) != 4 {
+		t.Errorf("unexpected actions: %v, expected 4 action got %d", actions, len(actions))
+	}
+}
+
 func tlsTestFile(t *testing.T, path string) string {
 	const tlsTestDir = "../../../testdata"
 	path = filepath.Join(tlsTestDir, path)

cmd/helm/installer/options.go

@@ -47,6 +47,9 @@ type Options struct {
 	// ServiceAccount is the Kubernetes service account to add to Tiller.
 	ServiceAccount string
 
+	// Force allows to force upgrading tiller if deployed version is greater than current version
+	ForceUpgrade bool
+
 	// ImageSpec indentifies the image Tiller will use when deployed.
 	//
 	// Valid if and only if UseCanary is false.

docs/helm/helm_init.md

@@ -36,6 +36,7 @@ helm init
       --canary-image             use the canary Tiller image
   -c, --client-only              if set does not install Tiller
       --dry-run                  do not install local or remote
+      --force-upgrade            force upgrade of Tiller to the current helm version
       --history-max int          limit the maximum number of revisions saved per release. Use 0 for no limit.
       --local-repo-url string    URL for local repository (default "http://127.0.0.1:8879/charts")
       --net-host                 install Tiller with net=host
@@ -68,4 +69,4 @@ helm init
 ### SEE ALSO
 * [helm](helm.md)	 - The Helm package manager for Kubernetes.
 
-###### Auto generated by spf13/cobra on 7-Nov-2017
+###### Auto generated by spf13/cobra on 9-Jan-2018