Add helm template --is-upgrade

Useful for toggling .Release.IsInstall / .Release.IsUpgrade which
in turn may cause templates to render differently.

cmd/helm/template.go

@@ -63,18 +63,19 @@ To render just one template in a chart, use '-x':
 `
 
 type templateCmd struct {
-	namespace    string
-	valueFiles   valueFiles
-	chartPath    string
-	out          io.Writer
-	values       []string
-	stringValues []string
-	nameTemplate string
-	showNotes    bool
-	releaseName  string
-	renderFiles  []string
-	kubeVersion  string
-	outputDir    string
+	namespace        string
+	valueFiles       valueFiles
+	chartPath        string
+	out              io.Writer
+	values           []string
+	stringValues     []string
+	nameTemplate     string
+	showNotes        bool
+	releaseName      string
+	releaseIsUpgrade bool
+	renderFiles      []string
+	kubeVersion      string
+	outputDir        string
 }
 
 func newTemplateCmd(out io.Writer) *cobra.Command {
@@ -93,6 +94,7 @@ func newTemplateCmd(out io.Writer) *cobra.Command {
 	f := cmd.Flags()
 	f.BoolVar(&t.showNotes, "notes", false, "show the computed NOTES.txt file as well")
 	f.StringVarP(&t.releaseName, "name", "n", "RELEASE-NAME", "release name")
+	f.BoolVar(&t.releaseIsUpgrade, "is-upgrade", false, "set .Release.IsUpgrade instead of .Release.IsInstall")
 	f.StringArrayVarP(&t.renderFiles, "execute", "x", []string{}, "only execute the given templates")
 	f.VarP(&t.valueFiles, "values", "f", "specify values in a YAML file (can specify multiple)")
 	f.StringVar(&t.namespace, "namespace", "", "namespace to install the release into")
@@ -159,6 +161,8 @@ func (t *templateCmd) run(cmd *cobra.Command, args []string) error {
 	}
 	options := chartutil.ReleaseOptions{
 		Name:      t.releaseName,
+		IsInstall: !t.releaseIsUpgrade,
+		IsUpgrade: t.releaseIsUpgrade,
 		Time:      timeconv.Now(),
 		Namespace: t.namespace,
 	}

cmd/helm/template_test.go

@@ -107,6 +107,20 @@ func TestTemplateCmd(t *testing.T) {
 			expectKey:   "subchart1/templates/service.yaml",
 			expectValue: "release-name: \"test\"",
 		},
+		{
+			name:        "check_release_is_install",
+			desc:        "verify --is-upgrade toggles .Release.IsInstall",
+			args:        []string{subchart1ChartPath, "--is-upgrade=false"},
+			expectKey:   "subchart1/templates/service.yaml",
+			expectValue: "release-is-install: \"true\"",
+		},
+		{
+			name:        "check_release_is_upgrade",
+			desc:        "verify --is-upgrade toggles .Release.IsUpgrade",
+			args:        []string{subchart1ChartPath, "--is-upgrade", "true"},
+			expectKey:   "subchart1/templates/service.yaml",
+			expectValue: "release-is-upgrade: \"true\"",
+		},
 		{
 			name:        "check_notes",
 			desc:        "verify --notes shows notes",

pkg/chartutil/testdata/subpop/charts/subchart1/templates/service.yaml

@@ -6,6 +6,8 @@ metadata:
     chart: "{{ .Chart.Name }}-{{ .Chart.Version }}"
     namespace: "{{ .Release.Namespace }}"
     release-name: "{{ .Release.Name }}"
+    release-is-upgrade: "{{ .Release.IsUpgrade }}"
+    release-is-install: "{{ .Release.IsInstall }}"
     kube-version/major: "{{ .Capabilities.KubeVersion.Major }}"
     kube-version/minor: "{{ .Capabilities.KubeVersion.Minor }}"
     kube-version/gitversion: "v{{ .Capabilities.KubeVersion.Major }}.{{ .Capabilities.KubeVersion.Minor }}.0"