🐛 use mgr.SetFields() for webhook server and implement injector interface for webhooks

Author: Mengqi Yu

pkg/webhook/admission/webhook.go

@@ -30,7 +30,6 @@ import (
 
 	admissionv1beta1 "k8s.io/api/admission/v1beta1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/runtime/inject"
 	atypes "sigs.k8s.io/controller-runtime/pkg/webhook/admission/types"
 	"sigs.k8s.io/controller-runtime/pkg/webhook/types"
@@ -210,24 +209,12 @@ func (w *Webhook) Validate() error {
 	return nil
 }
 
-var _ inject.Client = &Webhook{}
+var _ inject.Injector = &Webhook{}
 
-// InjectClient injects the client into the handlers
-func (w *Webhook) InjectClient(c client.Client) error {
+// InjectFunc injects dependencies into the handlers.
+func (w *Webhook) InjectFunc(f inject.Func) error {
 	for _, handler := range w.Handlers {
-		if _, err := inject.ClientInto(c, handler); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-var _ inject.Decoder = &Webhook{}
-
-// InjectDecoder injects the decoder into the handlers
-func (w *Webhook) InjectDecoder(d atypes.Decoder) error {
-	for _, handler := range w.Handlers {
-		if _, err := inject.DecoderInto(d, handler); err != nil {
+		if err := f(handler); err != nil {
 			return err
 		}
 	}

pkg/webhook/server.go

@@ -71,6 +71,9 @@ type Server struct {
 	// manager is the manager that this webhook server will be registered.
 	manager manager.Manager
 
+	// setFields is used to inject dependencies into webhooks
+	setFields func(i interface{}) error
+
 	// err will be non-nil if there is an error occur during initialization.
 	err error
 
@@ -160,7 +163,13 @@ func (s *Server) Complete() error {
 	if s.err != nil {
 		return s.err
 	}
-	// TODO(mengqiy): inject dependencies into each http.Handler
+
+	for path := range s.registry {
+		// Inject dependencies into each http.Handler
+		if err := s.setFields(s.registry[path]); err != nil {
+			return err
+		}
+	}
 	return s.manager.Add(s)
 }
 
@@ -214,18 +223,10 @@ func (s *Server) Start(stop <-chan struct{}) error {
 	return nil
 }
 
-var _ inject.Client = &Server{}
+var _ inject.Injector = &Server{}
 
-// InjectClient injects the client into the server
-func (s *Server) InjectClient(c client.Client) error {
-	s.Client = c
-	for path := range s.registry {
-		// TODO(mengqiy): remove this in PR #316
-		if wh, ok := s.registry[path].(Webhook); ok {
-			if _, err := inject.ClientInto(c, wh.Handler()); err != nil {
-				return err
-			}
-		}
-	}
+// InjectFunc injects dependencies into the handlers.
+func (s *Server) InjectFunc(f inject.Func) error {
+	s.setFields = f
 	return nil
 }