chore(admission server): make controller mutating specific

Signed-off-by: Wassim DHIF <wassim.dhif@datadoghq.com>

cmd/cluster-agent/admission/server.go

@@ -56,8 +56,8 @@ type MutateRequest struct {
 	APIClient kubernetes.Interface
 }
 
-// WebhookFunc is the function that runs the webhook logic
-type WebhookFunc func(request *MutateRequest) ([]byte, error)
+// MutatingWebhookFunc is the function that runs the mutating webhook logic
+type MutatingWebhookFunc func(request *MutateRequest) ([]byte, error)
 
 // Server TODO <container-integrations>
 type Server struct {
@@ -94,7 +94,7 @@ func (s *Server) initDecoder() {
 
 // Register adds an admission webhook handler.
 // Register must be called to register the desired webhook handlers before calling Run.
-func (s *Server) Register(uri string, webhookName string, f WebhookFunc, dc dynamic.Interface, apiClient kubernetes.Interface) {
+func (s *Server) Register(uri string, webhookName string, f MutatingWebhookFunc, dc dynamic.Interface, apiClient kubernetes.Interface) {
 	s.mux.HandleFunc(uri, func(w http.ResponseWriter, r *http.Request) {
 		s.mutateHandler(w, r, webhookName, f, dc, apiClient)
 	})
@@ -138,12 +138,12 @@ func (s *Server) Run(mainCtx context.Context, client kubernetes.Interface) error
 
 // mutateHandler contains the main logic responsible for handling mutation requests.
 // It supports both v1 and v1beta1 requests.
-func (s *Server) mutateHandler(w http.ResponseWriter, r *http.Request, webhookName string, mutateFunc WebhookFunc, dc dynamic.Interface, apiClient kubernetes.Interface) {
-	metrics.WebhooksReceived.Inc(webhookName)
+func (s *Server) mutateHandler(w http.ResponseWriter, r *http.Request, webhookName string, mutateFunc MutatingWebhookFunc, dc dynamic.Interface, apiClient kubernetes.Interface) {
+	metrics.MutatingWebhooksReceived.Inc(webhookName)
 
 	start := time.Now()
 	defer func() {
-		metrics.WebhooksResponseDuration.Observe(time.Since(start).Seconds(), webhookName)
+		metrics.MutatingWebhooksResponseDuration.Observe(time.Since(start).Seconds(), webhookName)
 	}()
 
 	if r.Method != http.MethodPost {

cmd/cluster-agent/subcommands/start/command.go

@@ -469,15 +469,15 @@ func start(log log.Component,
 			StopCh:              stopCh,
 		}
 
-		webhooks, err := admissionpkg.StartControllers(admissionCtx, wmeta, pa)
+		mutatingWebhooks, err := admissionpkg.StartControllers(admissionCtx, wmeta, pa)
 		if err != nil {
 			pkglog.Errorf("Could not start admission controller: %v", err)
 		} else {
 			// Webhook and secret controllers are started successfully
 			// Setup the k8s admission webhook server
 			server := admissioncmd.NewServer()
 
-			for _, webhookConf := range webhooks {
+			for _, webhookConf := range mutatingWebhooks {
 				server.Register(webhookConf.Endpoint(), webhookConf.Name(), webhookConf.MutateFunc(), apiCl.DynamicCl, apiCl.Cl)
 			}
 

pkg/clusteragent/admission/controllers/webhook/controller_base.go

@@ -37,7 +37,7 @@ import (
 // Controller is an interface implemented by ControllerV1 and ControllerV1beta1.
 type Controller interface {
 	Run(stopCh <-chan struct{})
-	EnabledWebhooks() []MutatingWebhook
+	EnabledMutatingWebhooks() []MutatingWebhook
 }
 
 // NewController returns the adequate implementation of the Controller interface.
@@ -76,7 +76,7 @@ type MutatingWebhook interface {
 	// should be invoked
 	LabelSelectors(useNamespaceSelector bool) (namespaceSelector *metav1.LabelSelector, objectSelector *metav1.LabelSelector)
 	// MutateFunc returns the function that mutates the resources
-	MutateFunc() admission.WebhookFunc
+	MutateFunc() admission.MutatingWebhookFunc
 }
 
 // mutatingWebhooks returns the list of mutating webhooks. Notice that the order
@@ -119,19 +119,19 @@ func mutatingWebhooks(wmeta workloadmeta.Component, pa workload.PodPatcher) []Mu
 // It contains the shared fields and provides shared methods.
 // For the nolint:structcheck see https://github.com/golangci/golangci-lint/issues/537
 type controllerBase struct {
-	clientSet        kubernetes.Interface //nolint:structcheck
-	config           Config
-	secretsLister    corelisters.SecretLister
-	secretsSynced    cache.InformerSynced //nolint:structcheck
-	webhooksSynced   cache.InformerSynced //nolint:structcheck
-	queue            workqueue.RateLimitingInterface
-	isLeaderFunc     func() bool
-	isLeaderNotif    <-chan struct{}
-	mutatingWebhooks []MutatingWebhook
+	clientSet              kubernetes.Interface //nolint:structcheck
+	config                 Config
+	secretsLister          corelisters.SecretLister
+	secretsSynced          cache.InformerSynced //nolint:structcheck
+	mutatingWebhooksSynced cache.InformerSynced //nolint:structcheck
+	queue                  workqueue.RateLimitingInterface
+	isLeaderFunc           func() bool
+	isLeaderNotif          <-chan struct{}
+	mutatingWebhooks       []MutatingWebhook
 }
 
-// EnabledWebhooks returns the list of enabled webhooks.
-func (c *controllerBase) EnabledWebhooks() []MutatingWebhook {
+// EnabledMutatingWebhooks returns the list of enabled mutating webhooks.
+func (c *controllerBase) EnabledMutatingWebhooks() []MutatingWebhook {
 	var res []MutatingWebhook
 
 	for _, webhook := range c.mutatingWebhooks {

pkg/clusteragent/admission/controllers/webhook/controller_v1.go

@@ -35,15 +35,15 @@ import (
 // It uses the admissionregistration/v1 API.
 type ControllerV1 struct {
 	controllerBase
-	webhooksLister   admissionlisters.MutatingWebhookConfigurationLister
-	webhookTemplates []admiv1.MutatingWebhook
+	mutatingWebhooksLister   admissionlisters.MutatingWebhookConfigurationLister
+	mutatingWebhookTemplates []admiv1.MutatingWebhook
 }
 
 // NewControllerV1 returns a new Webhook Controller using admissionregistration/v1.
 func NewControllerV1(
 	client kubernetes.Interface,
 	secretInformer coreinformers.SecretInformer,
-	webhookInformer admissioninformers.MutatingWebhookConfigurationInformer,
+	MutatingWebhookInformer admissioninformers.MutatingWebhookConfigurationInformer,
 	isLeaderFunc func() bool,
 	isLeaderNotif <-chan struct{},
 	config Config,
@@ -55,8 +55,8 @@ func NewControllerV1(
 	controller.config = config
 	controller.secretsLister = secretInformer.Lister()
 	controller.secretsSynced = secretInformer.Informer().HasSynced
-	controller.webhooksLister = webhookInformer.Lister()
-	controller.webhooksSynced = webhookInformer.Informer().HasSynced
+	controller.mutatingWebhooksLister = MutatingWebhookInformer.Lister()
+	controller.mutatingWebhooksSynced = MutatingWebhookInformer.Informer().HasSynced
 	controller.queue = workqueue.NewNamedRateLimitingQueue(workqueue.DefaultControllerRateLimiter(), "webhooks")
 	controller.isLeaderFunc = isLeaderFunc
 	controller.isLeaderNotif = isLeaderNotif
@@ -71,9 +71,9 @@ func NewControllerV1(
 		log.Errorf("cannot add event handler to secret informer: %v", err)
 	}
 
-	if _, err := webhookInformer.Informer().AddEventHandler(cache.ResourceEventHandlerFuncs{
+	if _, err := MutatingWebhookInformer.Informer().AddEventHandler(cache.ResourceEventHandlerFuncs{
 		AddFunc:    controller.handleWebhook,
-		UpdateFunc: controller.handleWebhookUpdate,
+		UpdateFunc: controller.handleMutatingWebhookUpdate,
 		DeleteFunc: controller.handleWebhook,
 	}); err != nil {
 		log.Errorf("cannot add event handler to webhook informer: %v", err)
@@ -90,7 +90,7 @@ func (c *ControllerV1) Run(stopCh <-chan struct{}) {
 	log.Infof("Starting webhook controller for secret %s/%s and webhook %s - Using admissionregistration/v1", c.config.getSecretNs(), c.config.getSecretName(), c.config.getWebhookName())
 	defer log.Infof("Stopping webhook controller for secret %s/%s and webhook %s", c.config.getSecretNs(), c.config.getSecretName(), c.config.getWebhookName())
 
-	if ok := cache.WaitForCacheSync(stopCh, c.secretsSynced, c.webhooksSynced); !ok {
+	if ok := cache.WaitForCacheSync(stopCh, c.secretsSynced, c.mutatingWebhooksSynced); !ok {
 		return
 	}
 
@@ -109,9 +109,9 @@ func (c *ControllerV1) run() {
 	}
 }
 
-// handleWebhookUpdate handles the new Webhook reported in update events.
+// handleMutatingWebhookUpdate handles the new Webhook reported in update events.
 // It can be a callback function for update events.
-func (c *ControllerV1) handleWebhookUpdate(oldObj, newObj interface{}) {
+func (c *ControllerV1) handleMutatingWebhookUpdate(oldObj, newObj interface{}) {
 	if !c.isLeaderFunc() {
 		return
 	}
@@ -142,51 +142,51 @@ func (c *ControllerV1) reconcile() error {
 		return err
 	}
 
-	webhook, err := c.webhooksLister.Get(c.config.getWebhookName())
+	mutatingWebhook, err := c.mutatingWebhooksLister.Get(c.config.getWebhookName())
 	if err != nil {
 		if errors.IsNotFound(err) {
-			log.Infof("Webhook %s was not found, creating it", c.config.getWebhookName())
-			return c.createWebhook(secret)
+			log.Infof("Mutating Webhook %s was not found, creating it", c.config.getWebhookName())
+			return c.createMutatingWebhook(secret)
 		}
 
 		return err
 	}
 
-	log.Debugf("The Webhook %s was found, updating it", c.config.getWebhookName())
+	log.Debugf("Mutating Webhook %s was found, updating it", c.config.getWebhookName())
 
-	return c.updateWebhook(secret, webhook)
+	return c.updateMutatingWebhook(secret, mutatingWebhook)
 }
 
-// createWebhook creates a new MutatingWebhookConfiguration object.
-func (c *ControllerV1) createWebhook(secret *corev1.Secret) error {
+// createMutatingWebhook creates a new MutatingWebhookConfiguration object.
+func (c *ControllerV1) createMutatingWebhook(secret *corev1.Secret) error {
 	webhook := &admiv1.MutatingWebhookConfiguration{
 		ObjectMeta: metav1.ObjectMeta{
 			Name: c.config.getWebhookName(),
 		},
-		Webhooks: c.newWebhooks(secret),
+		Webhooks: c.newMutatingWebhooks(secret),
 	}
 
 	_, err := c.clientSet.AdmissionregistrationV1().MutatingWebhookConfigurations().Create(context.TODO(), webhook, metav1.CreateOptions{})
 	if errors.IsAlreadyExists(err) {
-		log.Infof("Webhook %s already exists", webhook.GetName())
+		log.Infof("Mutating Webhook %s already exists", webhook.GetName())
 		return nil
 	}
 
 	return err
 }
 
-// updateWebhook stores a new configuration in the MutatingWebhookConfiguration object.
-func (c *ControllerV1) updateWebhook(secret *corev1.Secret, webhook *admiv1.MutatingWebhookConfiguration) error {
+// updateMutatingWebhook stores a new configuration in the MutatingWebhookConfiguration object.
+func (c *ControllerV1) updateMutatingWebhook(secret *corev1.Secret, webhook *admiv1.MutatingWebhookConfiguration) error {
 	webhook = webhook.DeepCopy()
-	webhook.Webhooks = c.newWebhooks(secret)
+	webhook.Webhooks = c.newMutatingWebhooks(secret)
 	_, err := c.clientSet.AdmissionregistrationV1().MutatingWebhookConfigurations().Update(context.TODO(), webhook, metav1.UpdateOptions{})
 	return err
 }
 
-// newWebhooks generates MutatingWebhook objects from config templates with updated CABundle from Secret.
-func (c *ControllerV1) newWebhooks(secret *corev1.Secret) []admiv1.MutatingWebhook {
+// newMutatingWebhooks generates MutatingWebhook objects from config templates with updated CABundle from Secret.
+func (c *ControllerV1) newMutatingWebhooks(secret *corev1.Secret) []admiv1.MutatingWebhook {
 	webhooks := []admiv1.MutatingWebhook{}
-	for _, tpl := range c.webhookTemplates {
+	for _, tpl := range c.mutatingWebhookTemplates {
 		tpl.ClientConfig.CABundle = certificate.GetCABundle(secret.Data)
 		webhooks = append(webhooks, tpl)
 	}
@@ -206,7 +206,7 @@ func (c *ControllerV1) generateTemplates() {
 
 		webhooks = append(
 			webhooks,
-			c.getWebhookSkeleton(
+			c.getMutatingWebhookSkeleton(
 				webhook.Name(),
 				webhook.Endpoint(),
 				webhook.Operations(),
@@ -217,10 +217,10 @@ func (c *ControllerV1) generateTemplates() {
 		)
 	}
 
-	c.webhookTemplates = webhooks
+	c.mutatingWebhookTemplates = webhooks
 }
 
-func (c *ControllerV1) getWebhookSkeleton(nameSuffix, path string, operations []admiv1.OperationType, resources []string, namespaceSelector, objectSelector *metav1.LabelSelector) admiv1.MutatingWebhook {
+func (c *ControllerV1) getMutatingWebhookSkeleton(nameSuffix, path string, operations []admiv1.OperationType, resources []string, namespaceSelector, objectSelector *metav1.LabelSelector) admiv1.MutatingWebhook {
 	matchPolicy := admiv1.Exact
 	sideEffects := admiv1.SideEffectClassNone
 	port := c.config.getServicePort()

pkg/clusteragent/admission/controllers/webhook/controller_v1_test.go

@@ -52,7 +52,7 @@ func TestSecretNotFoundV1(t *testing.T) {
 	defer close(stopCh)
 	c := f.run(stopCh)
 
-	_, err := c.webhooksLister.Get(v1Cfg.getWebhookName())
+	_, err := c.mutatingWebhooksLister.Get(v1Cfg.getWebhookName())
 	if !errors.IsNotFound(err) {
 		t.Fatal("Webhook shouldn't be created")
 	}
@@ -80,7 +80,7 @@ func TestCreateWebhookV1(t *testing.T) {
 
 	var webhook *admiv1.MutatingWebhookConfiguration
 	require.Eventually(t, func() bool {
-		webhook, err = c.webhooksLister.Get(v1Cfg.getWebhookName())
+		webhook, err = c.mutatingWebhooksLister.Get(v1Cfg.getWebhookName())
 		return err == nil
 	}, waitFor, tick)
 
@@ -129,7 +129,7 @@ func TestUpdateOutdatedWebhookV1(t *testing.T) {
 
 	var newWebhook *admiv1.MutatingWebhookConfiguration
 	require.Eventually(t, func() bool {
-		newWebhook, err = c.webhooksLister.Get(v1Cfg.getWebhookName())
+		newWebhook, err = c.mutatingWebhooksLister.Get(v1Cfg.getWebhookName())
 		return err == nil && !reflect.DeepEqual(webhook, newWebhook)
 	}, waitFor, tick)
 
@@ -965,7 +965,7 @@ func TestGenerateTemplatesV1(t *testing.T) {
 			c.mutatingWebhooks = mutatingWebhooks(wmeta, nil)
 			c.generateTemplates()
 
-			assert.EqualValues(t, tt.want(), c.webhookTemplates)
+			assert.EqualValues(t, tt.want(), c.mutatingWebhookTemplates)
 		})
 	}
 }