Annotate submariner broker ns on clusterSet object

This will be used by ACM Console/UI to identify the
associated broker namespace of the ManagedClusterSet.

Related to: stolostron/backlog#19293
Signed-off-by: Sridhar Gaddam <sgaddam@redhat.com>

pkg/hub/submarinerbroker/controller.go

@@ -7,16 +7,18 @@ import (
 
 	"github.com/openshift/library-go/pkg/controller/factory"
 	"github.com/openshift/library-go/pkg/operator/events"
+	"github.com/pkg/errors"
 	"github.com/stolostron/submariner-addon/pkg/constants"
 	brokerinfo "github.com/stolostron/submariner-addon/pkg/hub/submarinerbrokerinfo"
 	"github.com/stolostron/submariner-addon/pkg/resource"
 	"github.com/submariner-io/admiral/pkg/finalizer"
 	corev1 "k8s.io/api/core/v1"
-	"k8s.io/apimachinery/pkg/api/errors"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/api/meta"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/util/retry"
 	"k8s.io/klog/v2"
 	clientset "open-cluster-management.io/api/client/cluster/clientset/versioned/typed/cluster/v1beta1"
 	clusterinformerv1beta1 "open-cluster-management.io/api/client/cluster/informers/externalversions/cluster/v1beta1"
@@ -25,6 +27,7 @@ import (
 
 const (
 	brokerFinalizer      = "cluster.open-cluster-management.io/submariner-cleanup"
+	submBrokerNamespace  = "cluster.open-cluster-management.io/submariner-broker-ns"
 	ipSecPSKSecretLength = 48
 )
 
@@ -74,7 +77,7 @@ func (c *submarinerBrokerController) sync(ctx context.Context, syncCtx factory.S
 	klog.V(4).Infof("Reconciling ClusterSet %q", clusterSetName)
 
 	clusterSet, err := c.clusterSetLister.Get(clusterSetName)
-	if errors.IsNotFound(err) {
+	if apierrors.IsNotFound(err) {
 		// ClusterSet not found, could have been deleted, do nothing.
 		return nil
 	}
@@ -112,12 +115,19 @@ func (c *submarinerBrokerController) sync(ctx context.Context, syncCtx factory.S
 		return err
 	}
 
+	if clusterSet.GetAnnotations()[submBrokerNamespace] != config.SubmarinerNamespace {
+		err = c.annotateClusterSetWithBrokerNamespace(config.SubmarinerNamespace, clusterSetName)
+		if err != nil {
+			return err
+		}
+	}
+
 	return c.createIPSecPSKSecret(config.SubmarinerNamespace)
 }
 
 func (c *submarinerBrokerController) createIPSecPSKSecret(brokerNamespace string) error {
 	_, err := c.kubeClient.CoreV1().Secrets(brokerNamespace).Get(context.TODO(), constants.IPSecPSKSecretName, metav1.GetOptions{})
-	if errors.IsNotFound(err) {
+	if apierrors.IsNotFound(err) {
 		psk := make([]byte, ipSecPSKSecretLength)
 		if _, err := rand.Read(psk); err != nil {
 			return err
@@ -137,3 +147,31 @@ func (c *submarinerBrokerController) createIPSecPSKSecret(brokerNamespace string
 
 	return err
 }
+
+func (c *submarinerBrokerController) annotateClusterSetWithBrokerNamespace(brokerNamespace, clusterSetName string) error {
+	retryErr := retry.RetryOnConflict(retry.DefaultRetry, func() error {
+		clusterSet, err := c.clustersetClient.Get(context.TODO(), clusterSetName, metav1.GetOptions{})
+		if err != nil {
+			return errors.Wrapf(err, "unable to get clusterSet info for %q", clusterSetName)
+		}
+
+		annotations := clusterSet.GetAnnotations()
+		if annotations == nil {
+			annotations = map[string]string{}
+		}
+
+		annotations[submBrokerNamespace] = brokerNamespace
+		clusterSet.SetAnnotations(annotations)
+		_, updateErr := c.clustersetClient.Update(context.TODO(), clusterSet, metav1.UpdateOptions{})
+
+		return updateErr
+	})
+
+	if retryErr != nil {
+		return errors.Wrapf(retryErr, "error updating clusterSet annotation %q", clusterSetName)
+	}
+
+	klog.Infof("Successfully annotated clusterSet %q with brokerNamespace %q", clusterSetName, brokerNamespace)
+
+	return nil
+}