added warning and set default image for unreleased versions of helm for #3770 (#3781)

* added warning and set default image for unreleased versions of helm

* changed to BuildMetadata

* changed to BuildMetadata

* added check for clientOnly flag

cmd/helm/init.go

@@ -36,6 +36,7 @@ import (
 	"k8s.io/helm/pkg/helm/helmpath"
 	"k8s.io/helm/pkg/helm/portforwarder"
 	"k8s.io/helm/pkg/repo"
+	"k8s.io/helm/pkg/version"
 )
 
 const initDesc = `
@@ -315,6 +316,14 @@ func (i *initCmd) run() error {
 		fmt.Fprintln(i.out, "Not installing Tiller due to 'client-only' flag having been set")
 	}
 
+	needsDefaultImage := !i.clientOnly && !i.opts.UseCanary && len(i.opts.ImageSpec) == 0 && version.BuildMetadata == "unreleased"
+	if needsDefaultImage {
+		fmt.Fprintf(i.out, "\nWarning: You appear to be using an unreleased version of Helm. Please either use the\n"+
+			"--canary-image flag, or specify your desired tiller version with --tiller-image.\n\n"+
+			"Ex:\n"+
+			"$ helm init --tiller-image gcr.io/kubernetes-helm/tiller:v2.8.2\n\n")
+	}
+
 	fmt.Fprintln(i.out, "Happy Helming!")
 	return nil
 }

cmd/helm/installer/install_test.go

@@ -53,6 +53,10 @@ func TestDeployment(t *testing.T) {
 			t.Fatalf("%s: error %q", tt.name, err)
 		}
 
+		// Unreleased versions of helm don't have a release image. See issue 3370
+		if tt.name == "default" && version.BuildMetadata == "unreleased" {
+			tt.expect = "gcr.io/kubernetes-helm/tiller:canary"
+		}
 		if got := dep.Spec.Template.Spec.Containers[0].Image; got != tt.expect {
 			t.Errorf("%s: expected image %q, got %q", tt.name, tt.expect, got)
 		}

cmd/helm/installer/options.go

@@ -105,6 +105,9 @@ func (opts *Options) SelectImage() string {
 	case opts.UseCanary:
 		return defaultImage + ":canary"
 	case opts.ImageSpec == "":
+		if version.BuildMetadata == "unreleased" {
+			return defaultImage + ":canary"
+		}
 		return fmt.Sprintf("%s:%s", defaultImage, version.Version)
 	default:
 		return opts.ImageSpec