prevent unhandled errors on colliding poststarthook registration

Kubernetes-commit: 8d0c56e22f73fdb1a82a12475909e7d69f4bec08

pkg/server/config_test.go

@@ -57,7 +57,7 @@ func TestNewWithDelegate(t *testing.T) {
 	})
 
 	delegatePostStartHookChan := make(chan struct{})
-	delegateServer.AddPostStartHook("delegate-post-start-hook", func(context PostStartHookContext) error {
+	delegateServer.AddPostStartHookOrDie("delegate-post-start-hook", func(context PostStartHookContext) error {
 		defer close(delegatePostStartHookChan)
 		return nil
 	})
@@ -85,7 +85,7 @@ func TestNewWithDelegate(t *testing.T) {
 	})
 
 	wrappingPostStartHookChan := make(chan struct{})
-	wrappingServer.AddPostStartHook("wrapping-post-start-hook", func(context PostStartHookContext) error {
+	wrappingServer.AddPostStartHookOrDie("wrapping-post-start-hook", func(context PostStartHookContext) error {
 		defer close(wrappingPostStartHookChan)
 		return nil
 	})

pkg/server/hooks.go

@@ -92,7 +92,9 @@ func (s *GenericAPIServer) AddPostStartHook(name string, hook PostStartHookFunc)
 	// done is closed when the poststarthook is finished.  This is used by the health check to be able to indicate
 	// that the poststarthook is finished
 	done := make(chan struct{})
-	s.AddHealthzChecks(postStartHookHealthz{name: "poststarthook/" + name, done: done})
+	if err := s.AddHealthzChecks(postStartHookHealthz{name: "poststarthook/" + name, done: done}); err != nil {
+		return err
+	}
 	s.postStartHooks[name] = postStartHookEntry{hook: hook, done: done}
 
 	return nil

pkg/server/options/serving_test.go

@@ -496,7 +496,7 @@ func TestServerRunWithSNI(t *testing.T) {
 
 			// add poststart hook to know when the server is up.
 			startedCh := make(chan struct{})
-			s.AddPostStartHook("test-notifier", func(context PostStartHookContext) error {
+			s.AddPostStartHookOrDie("test-notifier", func(context PostStartHookContext) error {
 				close(startedCh)
 				return nil
 			})