Feat: Expose post-renderer flag in the upgrade subcommand

README.md

@@ -81,6 +81,7 @@ Examples:
 Flags:
   -h, --help                   help for upgrade
       --detailed-exitcode      return a non-zero exit code when there are changes
+      --post-renderer string   the path to an executable to be used for post rendering. If it exists in $PATH, the binary will be used, otherwise it will try to look for the executable at the given path
       --reset-values           reset the values to the ones built into the chart and merge in any new values
       --reuse-values           reuse the last release's values and merge in any new values
       --set stringArray        set values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)

cmd/helm3.go

@@ -95,6 +95,9 @@ func (d *diffCmd) template(isUpgrade bool) ([]byte, error) {
 	if d.namespace != "" {
 		flags = append(flags, "--namespace", d.namespace)
 	}
+	if d.postRenderer != "" {
+		flags = append(flags, "--post-renderer", d.postRenderer)
+	}
 	// Helm automatically enable --reuse-values when there's no --set, --set-string, --set-values, --set-file present.
 	// Let's simulate that in helm-diff.
 	// See https://medium.com/@kcatstack/understand-helm-upgrade-flags-reset-values-reuse-values-6e58ac8f127e

cmd/upgrade.go

@@ -33,6 +33,7 @@ type diffCmd struct {
 	suppressedKinds  []string
 	outputContext    int
 	showSecrets      bool
+	postRenderer     string
 }
 
 const globalUsage = `Show a diff explaining what a helm upgrade would change.
@@ -96,6 +97,7 @@ func newChartCommand() *cobra.Command {
 	f.BoolVar(&diff.devel, "devel", false, "use development versions, too. Equivalent to version '>0.0.0-0'. If --version is set, this is ignored.")
 	f.StringArrayVar(&diff.suppressedKinds, "suppress", []string{}, "allows suppression of the values listed in the diff output")
 	f.IntVarP(&diff.outputContext, "context", "C", -1, "output NUM lines of context around changes")
+	f.StringVar(&diff.postRenderer, "post-renderer", "", "the path to an executable to be used for post rendering. If it exists in $PATH, the binary will be used, otherwise it will try to look for the executable at the given path")
 	if !isHelm3() {
 		f.StringVar(&diff.namespace, "namespace", "default", "namespace to assume the release to be installed into")
 	}