Allow configuring custom ResourceVisitor in Install and Upgrade

Signed-off-by: Marko Lukša <marko.luksa@gmail.com>

pkg/action/install.go

@@ -104,6 +104,12 @@ type Install struct {
 	// OutputDir/<ReleaseName>
 	UseReleaseName bool
 	PostRenderer   postrender.PostRenderer
+	// ResourceVisitor is an optional VisitorFunc applied to each rendered resource
+	//
+	// This is an alternative to PostRenderer. Unike PostRenderer, it allows each
+	// individual resource to be modified without having to parse and re-serialize the
+	// manifests.
+	ResourceVisitor resource.VisitorFunc
 	// Lock to control raceconditions when the process receives a SIGTERM
 	Lock sync.Mutex
 }
@@ -302,6 +308,13 @@ func (i *Install) RunWithContext(ctx context.Context, chrt *chart.Chart, vals ma
 		return nil, errors.Wrap(err, "unable to build kubernetes objects from release manifest")
 	}
 
+	if i.ResourceVisitor != nil {
+		err = resources.Visit(i.ResourceVisitor)
+		if err != nil {
+			return nil, err
+		}
+	}
+
 	// It is safe to use "force" here because these are resources currently rendered by the chart.
 	err = resources.Visit(setMetadataVisitor(rel.Name, rel.Namespace, true))
 	if err != nil {

pkg/action/upgrade.go

@@ -98,6 +98,12 @@ type Upgrade struct {
 	// If this is non-nil, then after templates are rendered, they will be sent to the
 	// post renderer before sending to the Kubernetes API server.
 	PostRenderer postrender.PostRenderer
+	// ResourceVisitor is an optional VisitorFunc applied to each rendered resource
+	//
+	// This is an alternative to PostRenderer. Unike PostRenderer, it allows each
+	// individual resource to be modified without having to parse and re-serialize the
+	// manifests.
+	ResourceVisitor resource.VisitorFunc
 	// DisableOpenAPIValidation controls whether OpenAPI validation is enforced.
 	DisableOpenAPIValidation bool
 	// Get missing dependencies
@@ -285,6 +291,13 @@ func (u *Upgrade) performUpgrade(ctx context.Context, originalRelease, upgradedR
 		return upgradedRelease, errors.Wrap(err, "unable to build kubernetes objects from new release manifest")
 	}
 
+	if u.ResourceVisitor != nil {
+		err = target.Visit(u.ResourceVisitor)
+		if err != nil {
+			return upgradedRelease, err
+		}
+	}
+
 	// It is safe to use force only on target because these are resources currently rendered by the chart.
 	err = target.Visit(setMetadataVisitor(upgradedRelease.Name, upgradedRelease.Namespace, true))
 	if err != nil {