Give users the ability to disable namespace ownership of webhook conf…

…igurations
knative · Sep 23, 2024 · cf5f7be · cf5f7be
1 parent aaab500
commit cf5f7be
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Showing 7 changed files with 46 additions and 30 deletions.
diff --git a/webhook/configmaps/configmaps.go b/webhook/configmaps/configmaps.go
@@ -58,7 +58,8 @@ type reconciler struct {
 	vwhlister    admissionlisters.ValidatingWebhookConfigurationLister
 	secretlister corelisters.SecretLister
 
-	secretName string
+	secretName                string
+	disableNamespaceOwnership bool
 }
 
 var (
@@ -138,13 +139,15 @@ func (ac *reconciler) reconcileValidatingWebhook(ctx context.Context, caCert []b
 
 	webhook := configuredWebhook.DeepCopy()
 
-	// Set the owner to namespace.
-	ns, err := ac.client.CoreV1().Namespaces().Get(ctx, system.Namespace(), metav1.GetOptions{})
-	if err != nil {
-		return fmt.Errorf("failed to fetch namespace: %w", err)
+	if !ac.disableNamespaceOwnership {
+		// Set the owner to namespace.
+		ns, err := ac.client.CoreV1().Namespaces().Get(ctx, system.Namespace(), metav1.GetOptions{})
+		if err != nil {
+			return fmt.Errorf("failed to fetch namespace: %w", err)
+		}
+		nsRef := *metav1.NewControllerRef(ns, corev1.SchemeGroupVersion.WithKind("Namespace"))
+		webhook.OwnerReferences = []metav1.OwnerReference{nsRef}
 	}
-	nsRef := *metav1.NewControllerRef(ns, corev1.SchemeGroupVersion.WithKind("Namespace"))
-	webhook.OwnerReferences = []metav1.OwnerReference{nsRef}
 
 	for i, wh := range webhook.Webhooks {
 		if wh.Name != webhook.Name {

diff --git a/webhook/configmaps/controller.go b/webhook/configmaps/controller.go
@@ -60,8 +60,9 @@ func NewAdmissionController(
 		key:  key,
 		path: path,
 
-		constructors: make(map[string]reflect.Value),
-		secretName:   options.SecretName,
+		constructors:              make(map[string]reflect.Value),
+		secretName:                options.SecretName,
+		disableNamespaceOwnership: options.DisableNamespaceOwnership,
 
 		client:       client,
 		vwhlister:    vwhInformer.Lister(),

diff --git a/webhook/resourcesemantics/defaulting/controller.go b/webhook/resourcesemantics/defaulting/controller.go
@@ -100,9 +100,10 @@ func newController(ctx context.Context, name string, optsFunc ...OptionFunc) *co
 		handlers:  opts.types,
 		callbacks: opts.callbacks,
 
-		withContext:           opts.wc,
-		disallowUnknownFields: opts.disallowUnknownFields,
-		secretName:            wopts.SecretName,
+		withContext:               opts.wc,
+		disallowUnknownFields:     opts.disallowUnknownFields,
+		secretName:                wopts.SecretName,
+		disableNamespaceOwnership: wopts.DisableNamespaceOwnership,
 
 		client:       client,
 		mwhlister:    mwhInformer.Lister(),

diff --git a/webhook/resourcesemantics/defaulting/defaulting.go b/webhook/resourcesemantics/defaulting/defaulting.go
@@ -69,8 +69,9 @@ type reconciler struct {
 	mwhlister    admissionlisters.MutatingWebhookConfigurationLister
 	secretlister corelisters.SecretLister
 
-	disallowUnknownFields bool
-	secretName            string
+	disallowUnknownFields     bool
+	secretName                string
+	disableNamespaceOwnership bool
 }
 
 // CallbackFunc is the function to be invoked.
@@ -218,12 +219,14 @@ func (ac *reconciler) reconcileMutatingWebhook(ctx context.Context, caCert []byt
 
 	current := configuredWebhook.DeepCopy()
 
-	ns, err := ac.client.CoreV1().Namespaces().Get(ctx, system.Namespace(), metav1.GetOptions{})
-	if err != nil {
-		return fmt.Errorf("failed to fetch namespace: %w", err)
+	if !ac.disableNamespaceOwnership {
+		ns, err := ac.client.CoreV1().Namespaces().Get(ctx, system.Namespace(), metav1.GetOptions{})
+		if err != nil {
+			return fmt.Errorf("failed to fetch namespace: %w", err)
+		}
+		nsRef := *metav1.NewControllerRef(ns, corev1.SchemeGroupVersion.WithKind("Namespace"))
+		current.OwnerReferences = []metav1.OwnerReference{nsRef}
 	}
-	nsRef := *metav1.NewControllerRef(ns, corev1.SchemeGroupVersion.WithKind("Namespace"))
-	current.OwnerReferences = []metav1.OwnerReference{nsRef}
 
 	for i, wh := range current.Webhooks {
 		if wh.Name != current.Name {

diff --git a/webhook/resourcesemantics/validation/controller.go b/webhook/resourcesemantics/validation/controller.go
@@ -86,9 +86,10 @@ func newController(ctx context.Context, name string, optsFunc ...OptionFunc) *co
 		handlers:  opts.types,
 		callbacks: opts.callbacks,
 
-		withContext:           opts.wc,
-		disallowUnknownFields: opts.DisallowUnknownFields(),
-		secretName:            woptions.SecretName,
+		withContext:               opts.wc,
+		disallowUnknownFields:     opts.DisallowUnknownFields(),
+		secretName:                woptions.SecretName,
+		disableNamespaceOwnership: woptions.DisableNamespaceOwnership,
 
 		client:       client,
 		vwhlister:    vwhInformer.Lister(),

diff --git a/webhook/resourcesemantics/validation/reconcile_config.go b/webhook/resourcesemantics/validation/reconcile_config.go
@@ -60,8 +60,9 @@ type reconciler struct {
 	vwhlister    admissionlisters.ValidatingWebhookConfigurationLister
 	secretlister corelisters.SecretLister
 
-	disallowUnknownFields bool
-	secretName            string
+	disallowUnknownFields     bool
+	secretName                string
+	disableNamespaceOwnership bool
 }
 
 var (
@@ -193,13 +194,15 @@ func (ac *reconciler) reconcileValidatingWebhook(ctx context.Context, caCert []b
 
 	current := configuredWebhook.DeepCopy()
 
-	// Set the owner to namespace.
-	ns, err := ac.client.CoreV1().Namespaces().Get(ctx, system.Namespace(), metav1.GetOptions{})
-	if err != nil {
-		return fmt.Errorf("failed to fetch namespace: %w", err)
+	if !ac.disableNamespaceOwnership {
+		// Set the owner to namespace.
+		ns, err := ac.client.CoreV1().Namespaces().Get(ctx, system.Namespace(), metav1.GetOptions{})
+		if err != nil {
+			return fmt.Errorf("failed to fetch namespace: %w", err)
+		}
+		nsRef := *metav1.NewControllerRef(ns, corev1.SchemeGroupVersion.WithKind("Namespace"))
+		current.OwnerReferences = []metav1.OwnerReference{nsRef}
 	}
-	nsRef := *metav1.NewControllerRef(ns, corev1.SchemeGroupVersion.WithKind("Namespace"))
-	current.OwnerReferences = []metav1.OwnerReference{nsRef}
 
 	for i, wh := range current.Webhooks {
 		if wh.Name != current.Name {

diff --git a/webhook/webhook.go b/webhook/webhook.go
@@ -81,6 +81,10 @@ type Options struct {
 	// before shutting down.
 	GracePeriod time.Duration
 
+	// DisableNamespaceOwnership configures whether the webhook adds an owner reference for the SYSTEM_NAMESPACE
+	// Disabling this is useful when you expect the webhook configuration to be managed by something other than knative
+	DisableNamespaceOwnership bool
+
 	// ControllerOptions encapsulates options for creating a new controller,
 	// including throttling and stats behavior.
 	ControllerOptions *controller.ControllerOptions