New OffloadingStatus Controller

This new controller waits for all remote conditions of the offloaded namespace, and when the controller is able to get all of them, it sets the global offloading status according to these remote conditions.

pkg/consts/namespaceMapping.go

@@ -13,4 +13,11 @@ const (
 	NamespaceMapControllerFinalizer = "namespacemap-controller.liqo.io/finalizer"
 	// DocumentationURL is the URL to official Liqo Documentation.
 	DocumentationURL = "https://doc.liqo.io/"
+	// DefaultNameNamespaceOffloading is the default name of NamespaceOffloading resources, every namespace that have
+	// to be offloaded with Liqo, must have a NamespaceOffloading resource with this name.
+	DefaultNameNamespaceOffloading = "offloading"
+	// EnablingLiqoLabel is necessary in order to allow Pods to be scheduled on remote clusters.
+	EnablingLiqoLabel = "liqo.io/enabled"
+	// EnablingLiqoLabelValue unique value allowed for EnablingLiqoLabel.
+	EnablingLiqoLabelValue = "true"
 )

pkg/liqo-controller-manager/offloadingStatus-controller/doc.go

@@ -0,0 +1,2 @@
+// Package offloadingstatuscontroller contains OffloadingStatus Controller logic
+package offloadingstatuscontroller

pkg/liqo-controller-manager/offloadingStatus-controller/offloadingStatus_controller.go

@@ -0,0 +1,134 @@
+/*
+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 offloadingstatuscontroller
+
+import (
+	"context"
+	"reflect"
+
+	corev1 "k8s.io/api/core/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/klog"
+	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/event"
+	"sigs.k8s.io/controller-runtime/pkg/predicate"
+
+	offv1alpha1 "github.com/liqotech/liqo/apis/offloading/v1alpha1"
+	liqoconst "github.com/liqotech/liqo/pkg/consts"
+	liqoutils "github.com/liqotech/liqo/pkg/utils"
+)
+
+// OffloadingStatusReconciler checks the status of all remote namespaces associated with this
+// namespaceOffloading Resource, and sets the global offloading status only when there is a feedback
+// from all remote clusters.
+type OffloadingStatusReconciler struct {
+	client.Client
+	Scheme               *runtime.Scheme
+	RemoteClustersNumber int
+}
+
+// Reconcile checks if all remote Namespaces have been created with success or not.
+func (r *OffloadingStatusReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
+	namespaceOffloading := &offv1alpha1.NamespaceOffloading{}
+	if err := r.Get(ctx, types.NamespacedName{
+		Namespace: req.Namespace,
+		Name:      liqoconst.DefaultNameNamespaceOffloading,
+	}, namespaceOffloading); err != nil {
+		if apierrors.IsNotFound(err) {
+			klog.Infof("There is no NamespaceOffloading resource in Namespace '%s'", req.Namespace)
+			return ctrl.Result{}, nil
+		}
+		klog.Errorf("%s --> Unable to get namespaceOffloading for the namespace '%s'", err, req.Namespace)
+		return ctrl.Result{}, err
+	}
+
+	if r.RemoteClustersNumber == 0 {
+		virtualNodes := &corev1.NodeList{}
+		if err := r.List(context.TODO(), virtualNodes,
+			client.MatchingLabels{liqoconst.TypeLabel: liqoconst.TypeNode}); err != nil {
+			klog.Error(err, " --> Unable to List all virtual nodes")
+			return ctrl.Result{}, err
+		}
+		if len(virtualNodes.Items) == 0 {
+			klog.Info("No VirtualNodes at the moment in the cluster")
+			return ctrl.Result{}, nil
+		}
+		r.RemoteClustersNumber = len(virtualNodes.Items)
+	}
+
+	// if every remote Namespace has a condition
+	if len(namespaceOffloading.Status.RemoteNamespacesConditions) == r.RemoteClustersNumber {
+		ready := 0
+		notReady := 0
+
+		for i := range namespaceOffloading.Status.RemoteNamespacesConditions {
+			condition := liqoutils.GetNamespaceOffloadingCondition(namespaceOffloading.Status.RemoteNamespacesConditions[i],
+				offv1alpha1.NamespaceReady)
+			if condition == nil {
+				continue
+			}
+			if condition.Status == corev1.ConditionTrue {
+				ready++
+			} else {
+				notReady++
+			}
+		}
+
+		switch {
+		case ready == 0:
+			namespaceOffloading.Status.OffloadingPhase = offv1alpha1.AllFailedOffloadingPhaseType
+		case notReady == 0:
+			namespaceOffloading.Status.OffloadingPhase = offv1alpha1.ReadyOffloadingPhaseType
+		default:
+			namespaceOffloading.Status.OffloadingPhase = offv1alpha1.SomeFailedOffloadingPhaseType
+		}
+
+		if err := r.Update(ctx, namespaceOffloading); err != nil {
+			klog.Errorf("%s --> Unable to update namespaceOffloading for the namespace '%s'",
+				err, namespaceOffloading.Namespace)
+			return ctrl.Result{}, err
+		}
+	}
+
+	return ctrl.Result{}, nil
+}
+
+func checkNamespaceOffloadingStatus() predicate.Predicate {
+	return predicate.Funcs{
+		UpdateFunc: func(e event.UpdateEvent) bool {
+			// reconciles only when RemoteNamespacesConditions are updated
+			return !reflect.DeepEqual(e.ObjectOld.(*offv1alpha1.NamespaceOffloading).Status.RemoteNamespacesConditions,
+				e.ObjectNew.(*offv1alpha1.NamespaceOffloading).Status.RemoteNamespacesConditions) &&
+				e.ObjectNew.(*offv1alpha1.NamespaceOffloading).Status.OffloadingPhase != offv1alpha1.NoClusterSelectedOffloadingPhaseType
+		},
+		CreateFunc: func(e event.CreateEvent) bool {
+			return false
+		},
+		DeleteFunc: func(e event.DeleteEvent) bool {
+			return false
+		},
+	}
+}
+
+// SetupWithManager reconciles only on NamespaceOffloading Status updates.
+func (r *OffloadingStatusReconciler) SetupWithManager(mgr ctrl.Manager) error {
+	return ctrl.NewControllerManagedBy(mgr).
+		For(&offv1alpha1.NamespaceOffloading{}).
+		WithEventFilter(checkNamespaceOffloadingStatus()).
+		Complete(r)
+}