Refactor of VirtualNode-controller.

This commit allows to manage in a simpler way the NamespaceMap lifecycle.

pkg/consts/namespace_mapping.go

@@ -3,8 +3,8 @@ package consts
 const (
 	// RemoteClusterID is used to obtain cluster-id from different Liqo resources.
 	RemoteClusterID = "cluster-id" // "remote.liqo.io/clusterId"
-	// MapNamespaceName is the namespace where NamespaceMap are created.
-	MapNamespaceName = "default"
+	// TechnicalNamespace is the namespace where NamespaceMap are created.
+	TechnicalNamespace = "default"
 	// TypeLabel is the key of a Liqo label that identifies different types of nodes.
 	TypeLabel = "liqo.io/type"
 	// TypeNode is the value of a Liqo label that identifies Liqo virtual nodes.

pkg/liqo-controller-manager/virtualNode-controller/manage_virtualnode_controller_finalizer.go

@@ -0,0 +1,34 @@
+package virtualnodectrl
+
+import (
+	"context"
+
+	corev1 "k8s.io/api/core/v1"
+	"k8s.io/klog"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	ctrlutils "sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
+)
+
+func (r *VirtualNodeReconciler) checkVirtualNodeFinalizerPresence(ctx context.Context, n *corev1.Node) error {
+	if !ctrlutils.ContainsFinalizer(n, virtualNodeControllerFinalizer) {
+		original := n.DeepCopy()
+		ctrlutils.AddFinalizer(n, virtualNodeControllerFinalizer)
+		if err := r.Patch(ctx, n, client.MergeFrom(original)); err != nil {
+			klog.Errorf("%s --> Unable to add finalizer to the virtual-node '%s'", err, n.GetName())
+			return err
+		}
+		klog.Infof("Finalizer correctly added on the virtual-node '%s'", n.GetName())
+	}
+	return nil
+}
+
+func (r *VirtualNodeReconciler) removeVirtualNodeFinalizer(ctx context.Context, n *corev1.Node) error {
+	original := n.DeepCopy()
+	ctrlutils.RemoveFinalizer(n, virtualNodeControllerFinalizer)
+	if err := r.Patch(ctx, n, client.MergeFrom(original)); err != nil {
+		klog.Errorf("%s --> Unable to remove finalizer from the virtual-node '%s'", err, n.GetName())
+		return err
+	}
+	klog.Infof("Finalizer is correctly removed from the virtual-node '%s'", n.GetName())
+	return nil
+}

pkg/liqo-controller-manager/virtualNode-controller/namespaceMap_creation.go

@@ -0,0 +1,56 @@
+package virtualnodectrl
+
+import (
+	"context"
+	"fmt"
+
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/klog"
+	ctrlutils "sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
+
+	mapsv1alpha1 "github.com/liqotech/liqo/apis/virtualKubelet/v1alpha1"
+	liqoconst "github.com/liqotech/liqo/pkg/consts"
+
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+// create a new NamespaceMap with OwnerReference.
+func (r *VirtualNodeReconciler) createNamespaceMap(ctx context.Context, n *corev1.Node) error {
+	nm := &mapsv1alpha1.NamespaceMap{
+		ObjectMeta: metav1.ObjectMeta{
+			GenerateName: fmt.Sprintf("%s-", n.GetAnnotations()[liqoconst.RemoteClusterID]),
+			Namespace:    liqoconst.TechnicalNamespace,
+			Labels: map[string]string{
+				liqoconst.RemoteClusterID: n.GetAnnotations()[liqoconst.RemoteClusterID],
+			},
+		},
+	}
+
+	if err := ctrlutils.SetControllerReference(n, nm, r.Scheme); err != nil {
+		return err
+	}
+
+	if err := r.Create(ctx, nm); err != nil {
+		klog.Errorf("%s --> Problems in NamespaceMap creation for the virtual node '%s'", err, n.GetName())
+		return err
+	}
+	klog.Infof(" Create the NamespaceMap '%s' for the virtual node '%s'", nm.GetName(), n.GetName())
+	return nil
+}
+
+// This function manages NamespaceMaps Lifecycle on the basis of NamespaceMaps' number.
+func (r *VirtualNodeReconciler) checkNamespaceMapPresence(ctx context.Context, n *corev1.Node) error {
+	nms := &mapsv1alpha1.NamespaceMapList{}
+	if err := r.List(ctx, nms, client.InNamespace(liqoconst.TechnicalNamespace),
+		client.MatchingLabels{liqoconst.RemoteClusterID: n.GetAnnotations()[liqoconst.RemoteClusterID]}); err != nil {
+		klog.Errorf("%s --> Unable to List NamespaceMaps of virtual-node '%s'", err, n.GetName())
+		return err
+	}
+
+	if len(nms.Items) == 0 {
+		return r.createNamespaceMap(ctx, n)
+	}
+
+	return nil
+}