Flatten webhook types struct

This flattens down the webhook package structure, removing dedicated
`types` packages in favor of having things in the relevant places.  To
do this, the inject interface definitions for admission were also moved
to the admission controller location, but they actually make some amount
of sense living there.

It also renames and restructures a couple of the types for code clarity (e.g.
WebhookTypeMutating to MutatingWebhook) or to follow the convention of
other types in CR (e.g. Making wrapped types from core Kubernetes nested
fields).

Author: DirectXMan12

example/mutatingwebhook.go

@@ -23,22 +23,20 @@ import (
 
 	corev1 "k8s.io/api/core/v1"
 	"sigs.k8s.io/controller-runtime/pkg/client"
-	"sigs.k8s.io/controller-runtime/pkg/runtime/inject"
 	"sigs.k8s.io/controller-runtime/pkg/webhook/admission"
-	"sigs.k8s.io/controller-runtime/pkg/webhook/admission/types"
 )
 
 // podAnnotator annotates Pods
 type podAnnotator struct {
 	client  client.Client
-	decoder types.Decoder
+	decoder admission.Decoder
 }
 
 // Implement admission.Handler so the controller can handle admission request.
 var _ admission.Handler = &podAnnotator{}
 
 // podAnnotator adds an annotation to every incoming pods.
-func (a *podAnnotator) Handle(ctx context.Context, req types.Request) types.Response {
+func (a *podAnnotator) Handle(ctx context.Context, req admission.Request) admission.Response {
 	pod := &corev1.Pod{}
 
 	err := a.decoder.Decode(req, pod)
@@ -70,7 +68,6 @@ func (a *podAnnotator) mutatePodsFn(ctx context.Context, pod *corev1.Pod) error
 
 // podAnnotator implements inject.Client.
 // A client will be automatically injected.
-var _ inject.Client = &podAnnotator{}
 
 // InjectClient injects the client.
 func (a *podAnnotator) InjectClient(c client.Client) error {
@@ -80,10 +77,9 @@ func (a *podAnnotator) InjectClient(c client.Client) error {
 
 // podAnnotator implements inject.Decoder.
 // A decoder will be automatically injected.
-var _ inject.Decoder = &podAnnotator{}
 
 // InjectDecoder injects the decoder.
-func (a *podAnnotator) InjectDecoder(d types.Decoder) error {
+func (a *podAnnotator) InjectDecoder(d admission.Decoder) error {
 	a.decoder = d
 	return nil
 }

example/validatingwebhook.go

@@ -23,22 +23,20 @@ import (
 
 	corev1 "k8s.io/api/core/v1"
 	"sigs.k8s.io/controller-runtime/pkg/client"
-	"sigs.k8s.io/controller-runtime/pkg/runtime/inject"
 	"sigs.k8s.io/controller-runtime/pkg/webhook/admission"
-	"sigs.k8s.io/controller-runtime/pkg/webhook/admission/types"
 )
 
 // podValidator validates Pods
 type podValidator struct {
 	client  client.Client
-	decoder types.Decoder
+	decoder admission.Decoder
 }
 
 // Implement admission.Handler so the controller can handle admission request.
 var _ admission.Handler = &podValidator{}
 
 // podValidator admits a pod iff a specific annotation exists.
-func (v *podValidator) Handle(ctx context.Context, req types.Request) types.Response {
+func (v *podValidator) Handle(ctx context.Context, req admission.Request) admission.Response {
 	pod := &corev1.Pod{}
 
 	err := v.decoder.Decode(req, pod)
@@ -70,7 +68,6 @@ func (v *podValidator) validatePodsFn(ctx context.Context, pod *corev1.Pod) (boo
 
 // podValidator implements inject.Client.
 // A client will be automatically injected.
-var _ inject.Client = &podValidator{}
 
 // InjectClient injects the client.
 func (v *podValidator) InjectClient(c client.Client) error {
@@ -80,10 +77,9 @@ func (v *podValidator) InjectClient(c client.Client) error {
 
 // podValidator implements inject.Decoder.
 // A decoder will be automatically injected.
-var _ inject.Decoder = &podValidator{}
 
 // InjectDecoder injects the decoder.
-func (v *podValidator) InjectDecoder(d types.Decoder) error {
+func (v *podValidator) InjectDecoder(d admission.Decoder) error {
 	v.decoder = d
 	return nil
 }

pkg/manager/internal.go

@@ -37,7 +37,6 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/metrics"
 	"sigs.k8s.io/controller-runtime/pkg/recorder"
 	"sigs.k8s.io/controller-runtime/pkg/runtime/inject"
-	"sigs.k8s.io/controller-runtime/pkg/webhook/admission/types"
 )
 
 var log = logf.RuntimeLog.WithName("manager")
@@ -49,8 +48,6 @@ type controllerManager struct {
 	// scheme is the scheme injected into Controllers, EventHandlers, Sources and Predicates.  Defaults
 	// to scheme.scheme.
 	scheme *runtime.Scheme
-	// admissionDecoder is used to decode an admission.Request.
-	admissionDecoder types.Decoder
 
 	// runnables is the set of Controllers that the controllerManager injects deps into and Starts.
 	runnables []Runnable
@@ -136,9 +133,6 @@ func (cm *controllerManager) SetFields(i interface{}) error {
 	if _, err := inject.StopChannelInto(cm.internalStop, i); err != nil {
 		return err
 	}
-	if _, err := inject.DecoderInto(cm.admissionDecoder, i); err != nil {
-		return err
-	}
 	if _, err := inject.MapperInto(cm.mapper, i); err != nil {
 		return err
 	}
@@ -157,10 +151,6 @@ func (cm *controllerManager) GetScheme() *runtime.Scheme {
 	return cm.scheme
 }
 
-func (cm *controllerManager) GetAdmissionDecoder() types.Decoder {
-	return cm.admissionDecoder
-}
-
 func (cm *controllerManager) GetFieldIndexer() client.FieldIndexer {
 	return cm.fieldIndexes
 }

pkg/manager/manager.go

@@ -36,8 +36,6 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/leaderelection"
 	"sigs.k8s.io/controller-runtime/pkg/metrics"
 	"sigs.k8s.io/controller-runtime/pkg/recorder"
-	"sigs.k8s.io/controller-runtime/pkg/webhook/admission"
-	"sigs.k8s.io/controller-runtime/pkg/webhook/admission/types"
 )
 
 // Manager initializes shared dependencies such as Caches and Clients, and provides them to Runnables.
@@ -62,9 +60,6 @@ type Manager interface {
 	// GetScheme returns an initialized Scheme
 	GetScheme() *runtime.Scheme
 
-	// GetAdmissionDecoder returns the runtime.Decoder based on the scheme.
-	GetAdmissionDecoder() types.Decoder
-
 	// GetClient returns a client configured with the Config
 	GetClient() client.Client
 
@@ -135,7 +130,6 @@ type Options struct {
 	// Dependency injection for testing
 	newRecorderProvider func(config *rest.Config, scheme *runtime.Scheme, logger logr.Logger) (recorder.Provider, error)
 	newResourceLock     func(config *rest.Config, recorderProvider recorder.Provider, options leaderelection.Options) (resourcelock.Interface, error)
-	newAdmissionDecoder func(scheme *runtime.Scheme) (types.Decoder, error)
 	newMetricsListener  func(addr string) (net.Listener, error)
 }
 
@@ -210,11 +204,6 @@ func New(config *rest.Config, options Options) (Manager, error) {
 		return nil, err
 	}
 
-	admissionDecoder, err := options.newAdmissionDecoder(options.Scheme)
-	if err != nil {
-		return nil, err
-	}
-
 	// Create the mertics listener. This will throw an error if the metrics bind
 	// address is invalid or already in use.
 	metricsListener, err := options.newMetricsListener(options.MetricsBindAddress)
@@ -227,7 +216,6 @@ func New(config *rest.Config, options Options) (Manager, error) {
 	return &controllerManager{
 		config:           config,
 		scheme:           options.Scheme,
-		admissionDecoder: admissionDecoder,
 		errChan:          make(chan error),
 		cache:            cache,
 		fieldIndexes:     cache,
@@ -290,10 +278,6 @@ func setOptionsDefaults(options Options) Options {
 		options.newResourceLock = leaderelection.NewResourceLock
 	}
 
-	if options.newAdmissionDecoder == nil {
-		options.newAdmissionDecoder = admission.NewDecoder
-	}
-
 	if options.newMetricsListener == nil {
 		options.newMetricsListener = metrics.NewListener
 	}

pkg/runtime/inject/inject.go

@@ -22,7 +22,6 @@ import (
 	"k8s.io/client-go/rest"
 	"sigs.k8s.io/controller-runtime/pkg/cache"
 	"sigs.k8s.io/controller-runtime/pkg/client"
-	"sigs.k8s.io/controller-runtime/pkg/webhook/admission/types"
 )
 
 // Cache is used by the ControllerManager to inject Cache into Sources, EventHandlers, Predicates, and
@@ -70,20 +69,6 @@ func ClientInto(client client.Client, i interface{}) (bool, error) {
 	return false, nil
 }
 
-// Decoder is used by the ControllerManager to inject decoder into webhook handlers.
-type Decoder interface {
-	InjectDecoder(types.Decoder) error
-}
-
-// DecoderInto will set decoder on i and return the result if it implements Decoder.  Returns
-// false if i does not implement Decoder.
-func DecoderInto(decoder types.Decoder, i interface{}) (bool, error) {
-	if s, ok := i.(Decoder); ok {
-		return true, s.InjectDecoder(decoder)
-	}
-	return false, nil
-}
-
 // Scheme is used by the ControllerManager to inject Scheme into Sources, EventHandlers, Predicates, and
 // Reconciles
 type Scheme interface {

pkg/webhook/admission/builder/builder.go

@@ -18,7 +18,6 @@ package builder
 
 import (
 	"sigs.k8s.io/controller-runtime/pkg/webhook/admission"
-	"sigs.k8s.io/controller-runtime/pkg/webhook/types"
 )
 
 // WebhookBuilder builds a webhook based on the provided options.
@@ -37,7 +36,7 @@ type WebhookBuilder struct {
 
 	// t specifies the type of the webhook.
 	// Currently, Mutating and Validating are supported.
-	t *types.WebhookType
+	t *admission.WebhookType
 }
 
 // NewWebhookBuilder creates an empty WebhookBuilder.
@@ -55,15 +54,15 @@ func (b *WebhookBuilder) Name(name string) *WebhookBuilder {
 // Mutating sets the type to mutating admission webhook
 // Only one of Mutating and Validating can be invoked.
 func (b *WebhookBuilder) Mutating() *WebhookBuilder {
-	m := types.WebhookTypeMutating
+	m := admission.MutatingWebhook
 	b.t = &m
 	return b
 }
 
 // Validating sets the type to validating admission webhook
 // Only one of Mutating and Validating can be invoked.
 func (b *WebhookBuilder) Validating() *WebhookBuilder {
-	m := types.WebhookTypeValidating
+	m := admission.ValidatingWebhook
 	b.t = &m
 	return b
 }

pkg/webhook/admission/decode.go

@@ -19,16 +19,15 @@ package admission
 import (
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/serializer"
-	"sigs.k8s.io/controller-runtime/pkg/webhook/admission/types"
 )
 
-// DecodeFunc is a function that implements the Decoder interface.
-type DecodeFunc func(types.Request, runtime.Object) error
+// DecodeFunc is a function that implements an admission decoder in a single function.
+type DecodeFunc func(Request, runtime.Object) error
 
-var _ types.Decoder = DecodeFunc(nil)
+var _ Decoder = DecodeFunc(nil)
 
 // Decode implements the Decoder interface.
-func (f DecodeFunc) Decode(req types.Request, obj runtime.Object) error {
+func (f DecodeFunc) Decode(req Request, obj runtime.Object) error {
 	return f(req, obj)
 }
 
@@ -37,12 +36,12 @@ type decoder struct {
 }
 
 // NewDecoder creates a Decoder given the runtime.Scheme
-func NewDecoder(scheme *runtime.Scheme) (types.Decoder, error) {
+func NewDecoder(scheme *runtime.Scheme) (Decoder, error) {
 	return decoder{codecs: serializer.NewCodecFactory(scheme)}, nil
 }
 
 // Decode decodes the inlined object in the AdmissionRequest into the passed-in runtime.Object.
-func (d decoder) Decode(req types.Request, into runtime.Object) error {
+func (d decoder) Decode(req Request, into runtime.Object) error {
 	deserializer := d.codecs.UniversalDeserializer()
 	return runtime.DecodeInto(deserializer, req.AdmissionRequest.Object.Raw, into)
 }

pkg/webhook/admission/decode_test.go

@@ -24,11 +24,10 @@ import (
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/client-go/kubernetes/scheme"
-	"sigs.k8s.io/controller-runtime/pkg/webhook/admission/types"
 )
 
 var _ = Describe("admission webhook decoder", func() {
-	var decoder types.Decoder
+	var decoder Decoder
 	BeforeEach(func(done Done) {
 		var err error
 		decoder, err = NewDecoder(scheme.Scheme)
@@ -46,8 +45,8 @@ var _ = Describe("admission webhook decoder", func() {
 	})
 
 	Describe("Decode", func() {
-		req := types.Request{
-			AdmissionRequest: &admissionv1beta1.AdmissionRequest{
+		req := Request{
+			AdmissionRequest: admissionv1beta1.AdmissionRequest{
 				Object: runtime.RawExtension{
 					Raw: []byte(`{
     "apiVersion": "v1",

pkg/webhook/admission/http.go

@@ -31,7 +31,6 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/serializer"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
-	"sigs.k8s.io/controller-runtime/pkg/webhook/admission/types"
 	"sigs.k8s.io/controller-runtime/pkg/webhook/internal/metrics"
 )
 
@@ -55,7 +54,7 @@ func (wh *Webhook) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	var body []byte
 	var err error
 
-	var reviewResponse types.Response
+	var reviewResponse Response
 	if r.Body != nil {
 		if body, err = ioutil.ReadAll(r.Body); err != nil {
 			log.Error(err, "unable to read the body from the incoming request")
@@ -81,7 +80,11 @@ func (wh *Webhook) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	ar := v1beta1.AdmissionReview{}
+	req := Request{}
+	ar := v1beta1.AdmissionReview{
+		// avoid an extra copy
+		Request: &req.AdmissionRequest,
+	}
 	if _, _, err := admissionv1beta1schemecodecs.UniversalDeserializer().Decode(body, nil, &ar); err != nil {
 		log.Error(err, "unable to decode the request")
 		reviewResponse = ErrorResponse(http.StatusBadRequest, err)
@@ -90,13 +93,13 @@ func (wh *Webhook) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 
 	// TODO: add panic-recovery for Handle
-	reviewResponse = wh.Handle(context.Background(), types.Request{AdmissionRequest: ar.Request})
+	reviewResponse = wh.Handle(context.Background(), req)
 	wh.writeResponse(w, reviewResponse)
 }
 
-func (wh *Webhook) writeResponse(w io.Writer, response types.Response) {
-	if response.Response.Result.Code != 0 {
-		if response.Response.Result.Code == http.StatusOK {
+func (wh *Webhook) writeResponse(w io.Writer, response Response) {
+	if response.Result.Code != 0 {
+		if response.Result.Code == http.StatusOK {
 			metrics.TotalRequests.WithLabelValues(wh.Name, "true").Inc()
 		} else {
 			metrics.TotalRequests.WithLabelValues(wh.Name, "false").Inc()
@@ -105,7 +108,7 @@ func (wh *Webhook) writeResponse(w io.Writer, response types.Response) {
 
 	encoder := json.NewEncoder(w)
 	responseAdmissionReview := v1beta1.AdmissionReview{
-		Response: response.Response,
+		Response: &response.AdmissionResponse,
 	}
 	err := encoder.Encode(responseAdmissionReview)
 	if err != nil {