Watch and reconcile operator-controlled ConfigMaps

If users apply configmap changes directly, the operator wasn't
reverting those changes instantly; with this PR, it will watch
applied ConfigMaps and apply `KnativeServing` and `KnativeEventing`
configurations.

Signed-off-by: Pierangelo Di Pilato <pierdipi@redhat.com>

Author: pierDipi

cmd/operator/main.go

@@ -19,11 +19,18 @@ package main
 import (
 	"knative.dev/operator/pkg/reconciler/knativeeventing"
 	"knative.dev/operator/pkg/reconciler/knativeserving"
+	kubefilteredfactory "knative.dev/pkg/client/injection/kube/informers/factory/filtered"
 	"knative.dev/pkg/injection/sharedmain"
+	"knative.dev/pkg/signals"
 )
 
 func main() {
-	sharedmain.Main("knative-operator",
+	ctx := signals.NewContext()
+	ctx = kubefilteredfactory.WithSelectors(ctx,
+		knativeserving.Selector,
+		knativeeventing.Selector,
+	)
+	sharedmain.MainWithContext(ctx, "knative-operator",
 		knativeserving.NewController,
 		knativeeventing.NewController,
 	)

pkg/reconciler/common/transformers.go

@@ -83,3 +83,15 @@ func InjectNamespace(manifest *mf.Manifest, instance base.KComponent, extra ...m
 	*manifest = m
 	return nil
 }
+
+func InjectLabel(key, value string) mf.Transformer {
+	return func(u *unstructured.Unstructured) error {
+		curr := u.GetLabels()
+		if curr == nil {
+			curr = map[string]string{}
+		}
+		curr[key] = value
+		u.SetLabels(curr)
+		return nil
+	}
+}

pkg/reconciler/knativeeventing/controller.go

@@ -28,13 +28,20 @@ import (
 	knereconciler "knative.dev/operator/pkg/client/injection/reconciler/operator/v1beta1/knativeeventing"
 	"knative.dev/operator/pkg/reconciler/common"
 	kubeclient "knative.dev/pkg/client/injection/kube/client"
-	deploymentinformer "knative.dev/pkg/client/injection/kube/informers/apps/v1/deployment"
+	deploymentinformer "knative.dev/pkg/client/injection/kube/informers/apps/v1/deployment/filtered"
+	configmapinformer "knative.dev/pkg/client/injection/kube/informers/core/v1/configmap/filtered"
 	"knative.dev/pkg/configmap"
 	"knative.dev/pkg/controller"
 	"knative.dev/pkg/injection"
 	"knative.dev/pkg/logging"
 )
 
+const (
+	SelectorKey   = "app.kubernetes.io/name"
+	SelectorValue = "knative-eventing"
+	Selector      = SelectorKey + "=" + SelectorValue
+)
+
 // NewController initializes the controller and is called by the generated code
 // Registers eventhandlers to enqueue events
 func NewController(ctx context.Context, cmw configmap.Watcher) *controller.Impl {
@@ -45,7 +52,8 @@ func NewController(ctx context.Context, cmw configmap.Watcher) *controller.Impl
 func NewExtendedController(generator common.ExtensionGenerator) injection.ControllerConstructor {
 	return func(ctx context.Context, cmw configmap.Watcher) *controller.Impl {
 		knativeEventingInformer := knativeEventinginformer.Get(ctx)
-		deploymentInformer := deploymentinformer.Get(ctx)
+		deploymentInformer := deploymentinformer.Get(ctx, Selector)
+		configMapInformer := configmapinformer.Get(ctx, Selector)
 		kubeClient := kubeclient.Get(ctx)
 		logger := logging.FromContext(ctx)
 
@@ -72,6 +80,10 @@ func NewExtendedController(generator common.ExtensionGenerator) injection.Contro
 			FilterFunc: controller.FilterControllerGVK(v1beta1.SchemeGroupVersion.WithKind("KnativeEventing")),
 			Handler:    controller.HandleAll(impl.EnqueueControllerOf),
 		})
+		configMapInformer.Informer().AddEventHandler(cache.FilteringResourceEventHandler{
+			FilterFunc: controller.FilterControllerGVK(v1beta1.SchemeGroupVersion.WithKind("KnativeEventing")),
+			Handler:    controller.HandleAll(impl.EnqueueControllerOf),
+		})
 
 		return impl
 	}

pkg/reconciler/knativeeventing/knativeeventing.go

@@ -160,6 +160,8 @@ func (r *Reconciler) transform(ctx context.Context, manifest *mf.Manifest, comp
 		kec.DefaultBrokerConfigMapTransform(instance, logger),
 		kec.SinkBindingSelectionModeTransform(instance, logger),
 		kec.ReplicasEnvVarsTransform(manifest.Client),
+		// Ensure all resources have the selector applied so that the controller re-queues applied resources when they change.
+		common.InjectLabel(SelectorKey, SelectorValue),
 	}
 	extra = append(extra, r.extension.Transformers(instance)...)
 	return common.Transform(ctx, manifest, instance, extra...)

pkg/reconciler/knativeserving/controller.go

@@ -28,7 +28,8 @@ import (
 	knsreconciler "knative.dev/operator/pkg/client/injection/reconciler/operator/v1beta1/knativeserving"
 	"knative.dev/operator/pkg/reconciler/common"
 	kubeclient "knative.dev/pkg/client/injection/kube/client"
-	deploymentinformer "knative.dev/pkg/client/injection/kube/informers/apps/v1/deployment"
+	deploymentinformer "knative.dev/pkg/client/injection/kube/informers/apps/v1/deployment/filtered"
+	configmapinformer "knative.dev/pkg/client/injection/kube/informers/core/v1/configmap/filtered"
 	"knative.dev/pkg/configmap"
 	"knative.dev/pkg/controller"
 	"knative.dev/pkg/injection"
@@ -41,11 +42,18 @@ func NewController(ctx context.Context, cmw configmap.Watcher) *controller.Impl
 	return NewExtendedController(common.NoExtension)(ctx, cmw)
 }
 
+const (
+	SelectorKey   = "app.kubernetes.io/name"
+	SelectorValue = "knative-serving"
+	Selector      = SelectorKey + "=" + SelectorValue
+)
+
 // NewExtendedController returns a controller extended to a specific platform
 func NewExtendedController(generator common.ExtensionGenerator) injection.ControllerConstructor {
 	return func(ctx context.Context, cmw configmap.Watcher) *controller.Impl {
 		knativeServingInformer := knativeServinginformer.Get(ctx)
-		deploymentInformer := deploymentinformer.Get(ctx)
+		deploymentInformer := deploymentinformer.Get(ctx, Selector)
+		configMapInformer := configmapinformer.Get(ctx, Selector)
 		kubeClient := kubeclient.Get(ctx)
 		logger := logging.FromContext(ctx)
 
@@ -72,6 +80,10 @@ func NewExtendedController(generator common.ExtensionGenerator) injection.Contro
 			FilterFunc: controller.FilterControllerGVK(v1beta1.SchemeGroupVersion.WithKind("KnativeServing")),
 			Handler:    controller.HandleAll(impl.EnqueueControllerOf),
 		})
+		configMapInformer.Informer().AddEventHandler(cache.FilteringResourceEventHandler{
+			FilterFunc: controller.FilterControllerGVK(v1beta1.SchemeGroupVersion.WithKind("KnativeServing")),
+			Handler:    controller.HandleAll(impl.EnqueueControllerOf),
+		})
 
 		return impl
 	}

pkg/reconciler/knativeserving/knativeserving.go

@@ -142,6 +142,8 @@ func (r *Reconciler) transform(ctx context.Context, manifest *mf.Manifest, comp
 	extra := []mf.Transformer{
 		ksc.CustomCertsTransform(instance, logger),
 		ksc.AggregationRuleTransform(manifest.Client),
+		// Ensure all resources have the selector applied so that the controller re-queues applied resources when they change.
+		common.InjectLabel(SelectorKey, SelectorValue),
 	}
 	extra = append(extra, r.extension.Transformers(instance)...)
 	extra = append(extra, ingress.Transformers(ctx, instance)...)

…formers/apps/v1/deployment/deployment.go …pps/v1/deployment/filtered/deployment.govendor/knative.dev/pkg/client/injection/kube/informers/apps/v1/deployment/deployment.go renamed to vendor/knative.dev/pkg/client/injection/kube/informers/apps/v1/deployment/filtered/deployment.go vendor/knative.dev/pkg/client/injection/kube/informers/apps/v1/deployment/deployment.go renamed to vendor/knative.dev/pkg/client/injection/kube/informers/apps/v1/deployment/filtered/deployment.go

@@ -1491,8 +1491,9 @@ knative.dev/pkg/client/injection/ducks/duck/v1/addressable
 knative.dev/pkg/client/injection/ducks/duck/v1/authstatus
 knative.dev/pkg/client/injection/kube/client
 knative.dev/pkg/client/injection/kube/client/fake
-knative.dev/pkg/client/injection/kube/informers/apps/v1/deployment
-knative.dev/pkg/client/injection/kube/informers/factory
+knative.dev/pkg/client/injection/kube/informers/apps/v1/deployment/filtered
+knative.dev/pkg/client/injection/kube/informers/core/v1/configmap/filtered
+knative.dev/pkg/client/injection/kube/informers/factory/filtered
 knative.dev/pkg/codegen/cmd/injection-gen
 knative.dev/pkg/codegen/cmd/injection-gen/args
 knative.dev/pkg/codegen/cmd/injection-gen/generators