Add a namespace controller for the MT Broker.

cmd/mtchannel_broker/main.go

@@ -23,10 +23,12 @@ import (
 	"knative.dev/pkg/injection/sharedmain"
 
 	"knative.dev/eventing/pkg/reconciler/mtbroker"
+	"knative.dev/eventing/pkg/reconciler/mtnamespace"
 )
 
 func main() {
 	sharedmain.Main("mt-broker-controller",
+		mtnamespace.NewController,
 		mtbroker.NewController,
 	)
 }

pkg/reconciler/mtnamespace/controller.go

@@ -0,0 +1,70 @@
+/*
+Copyright 2020 The Knative Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mtnamespace
+
+import (
+	"context"
+
+	corev1 "k8s.io/api/core/v1"
+	"k8s.io/client-go/tools/cache"
+	"knative.dev/pkg/configmap"
+	"knative.dev/pkg/controller"
+
+	"knative.dev/eventing/pkg/reconciler"
+
+	"knative.dev/eventing/pkg/client/injection/informers/eventing/v1beta1/broker"
+	"knative.dev/pkg/client/injection/kube/informers/core/v1/namespace"
+)
+
+const (
+	// ReconcilerName is the name of the reconciler
+	ReconcilerName = "Namespace" // TODO: Namespace is not a very good name for this controller.
+
+	// controllerAgentName is the string used by this controller to identify
+	// itself when creating events.
+	controllerAgentName = "knative-eventing-namespace-controller"
+)
+
+// NewController initializes the controller and is called by the generated code
+// Registers event handlers to enqueue events
+func NewController(
+	ctx context.Context,
+	cmw configmap.Watcher,
+) *controller.Impl {
+
+	namespaceInformer := namespace.Get(ctx)
+	brokerInformer := broker.Get(ctx)
+
+	r := &Reconciler{
+		Base:            reconciler.NewBase(ctx, controllerAgentName, cmw),
+		namespaceLister: namespaceInformer.Lister(),
+		brokerLister:    brokerInformer.Lister(),
+	}
+
+	impl := controller.NewImpl(r, r.Logger, ReconcilerName)
+	// TODO: filter label selector: on InjectionEnabledLabels()
+
+	r.Logger.Info("Setting up event handlers")
+	namespaceInformer.Informer().AddEventHandler(controller.HandleAll(impl.Enqueue))
+	brokerInformer.Informer().AddEventHandler(
+		cache.FilteringResourceEventHandler{
+			FilterFunc: controller.FilterGroupVersionKind(corev1.SchemeGroupVersion.WithKind("Namespace")),
+			Handler:    controller.HandleAll(impl.EnqueueControllerOf),
+		})
+
+	return impl
+}

pkg/reconciler/mtnamespace/controller_test.go

@@ -0,0 +1,38 @@
+/*
+Copyright 2020 The Knative Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mtnamespace
+
+import (
+	"testing"
+
+	"knative.dev/pkg/configmap"
+	. "knative.dev/pkg/reconciler/testing"
+
+	// Fake injection informers
+	_ "knative.dev/eventing/pkg/client/injection/informers/eventing/v1beta1/broker/fake"
+	_ "knative.dev/pkg/client/injection/kube/informers/core/v1/namespace/fake"
+)
+
+func TestNew(t *testing.T) {
+	ctx, _ := SetupFakeContext(t)
+
+	c := NewController(ctx, configmap.NewStaticWatcher())
+
+	if c == nil {
+		t.Fatal("Expected NewController to return a non-nil value")
+	}
+}

pkg/reconciler/mtnamespace/namespace.go

@@ -0,0 +1,135 @@
+/*
+Copyright 2020 The Knative Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mtnamespace
+
+import (
+	"context"
+	"fmt"
+
+	"k8s.io/client-go/tools/cache"
+	"knative.dev/eventing/pkg/reconciler/mtnamespace/resources"
+
+	corev1listers "k8s.io/client-go/listers/core/v1"
+	eventinglisters "knative.dev/eventing/pkg/client/listers/eventing/v1beta1"
+
+	"go.uber.org/zap"
+	corev1 "k8s.io/api/core/v1"
+	apierrs "k8s.io/apimachinery/pkg/api/errors"
+	k8serrors "k8s.io/apimachinery/pkg/api/errors"
+	"knative.dev/eventing/pkg/apis/eventing/v1alpha1"
+	"knative.dev/eventing/pkg/apis/eventing/v1beta1"
+	"knative.dev/eventing/pkg/logging"
+	"knative.dev/eventing/pkg/reconciler"
+	"knative.dev/pkg/controller"
+)
+
+const (
+	namespaceReconciled       = "NamespaceReconciled"
+	namespaceReconcileFailure = "NamespaceReconcileFailure"
+
+	// Name of the corev1.Events emitted from the reconciliation process.
+	brokerCreated = "BrokerCreated"
+)
+
+var (
+	brokerGVK = v1alpha1.SchemeGroupVersion.WithKind("Broker")
+)
+
+type Reconciler struct {
+	*reconciler.Base
+
+	// listers index properties about resources
+	namespaceLister corev1listers.NamespaceLister
+	brokerLister    eventinglisters.BrokerLister
+}
+
+// Check that our Reconciler implements controller.Reconciler
+var _ controller.Reconciler = (*Reconciler)(nil)
+
+// Reconcile compares the actual state with the desired, and attempts to
+// converge the two. It then updates the Status block of the Namespace resource
+// with the current status of the resource.
+func (r *Reconciler) Reconcile(ctx context.Context, key string) error {
+	_, name, err := cache.SplitMetaNamespaceKey(key)
+	if err != nil {
+		logging.FromContext(ctx).Error("invalid resource key")
+		return nil
+	}
+
+	// Get the namespace resource with this namespace/name
+	original, err := r.namespaceLister.Get(name)
+	if apierrs.IsNotFound(err) {
+		// The resource may no longer exist, in which case we stop processing.
+		logging.FromContext(ctx).Error("namespace key in work queue no longer exists")
+		return nil
+	} else if err != nil {
+		return err
+	}
+
+	if original.Labels[resources.InjectionLabelKey] == resources.InjectionDisabledLabelValue {
+		logging.FromContext(ctx).Debug("Not reconciling Namespace")
+		return nil
+	}
+
+	// Don't modify the informers copy
+	ns := original.DeepCopy()
+
+	// Reconcile this copy of the Namespace.
+	reconcileErr := r.reconcile(ctx, ns)
+	if reconcileErr != nil {
+		logging.FromContext(ctx).Error("Error reconciling Namespace", zap.Error(reconcileErr))
+		r.Recorder.Eventf(ns, corev1.EventTypeWarning, namespaceReconcileFailure, "Failed to reconcile Namespace: %v", reconcileErr)
+	} else {
+		logging.FromContext(ctx).Debug("Namespace reconciled")
+		r.Recorder.Eventf(ns, corev1.EventTypeNormal, namespaceReconciled, "Namespace reconciled: %q", ns.Name)
+	}
+
+	return reconcileErr
+}
+
+func (r *Reconciler) reconcile(ctx context.Context, ns *corev1.Namespace) error {
+	if ns.DeletionTimestamp != nil {
+		return nil
+	}
+
+	if _, err := r.reconcileBroker(ctx, ns); err != nil {
+		return fmt.Errorf("broker: %v", err)
+	}
+
+	return nil
+}
+
+// reconcileBroker reconciles the default Broker for the Namespace 'ns'.
+func (r *Reconciler) reconcileBroker(ctx context.Context, ns *corev1.Namespace) (*v1beta1.Broker, error) {
+	current, err := r.brokerLister.Brokers(ns.Name).Get(resources.DefaultBrokerName)
+
+	// If the resource doesn't exist, we'll create it.
+	if k8serrors.IsNotFound(err) {
+		b := resources.MakeBroker(ns)
+		b, err = r.EventingClientSet.EventingV1beta1().Brokers(ns.Name).Create(b)
+		if err != nil {
+			return nil, err
+		}
+		r.Recorder.Event(ns, corev1.EventTypeNormal, brokerCreated,
+			"Default eventing.knative.dev Broker created.")
+		return b, nil
+	} else if err != nil {
+		return nil, err
+	}
+	// Don't update anything that is already present.
+	return current, nil
+}