feat: use new property name for node count property + specify the core properties (node count, total/allocatable/available CPU/memory)

cmd/memberagent/main.go

@@ -46,15 +46,15 @@ import (
 	workv1alpha1controller "go.goms.io/fleet/pkg/controllers/workv1alpha1"
 	fleetmetrics "go.goms.io/fleet/pkg/metrics"
 	"go.goms.io/fleet/pkg/propertyprovider"
-	"go.goms.io/fleet/pkg/propertyprovider/aks"
+	"go.goms.io/fleet/pkg/propertyprovider/azure"
 	"go.goms.io/fleet/pkg/utils"
 	"go.goms.io/fleet/pkg/utils/httpclient"
 	//+kubebuilder:scaffold:imports
 )
 
 const (
 	// The list of available property provider names.
-	aksPropertyProvider = "azure"
+	azurePropertyProvider = "azure"
 )
 
 var (
@@ -351,11 +351,11 @@ func Start(ctx context.Context, hubCfg, memberConfig *rest.Config, hubOpts, memb
 		// Set up a provider provider (if applicable).
 		var pp propertyprovider.PropertyProvider
 		switch {
-		case propertyProvider != nil && *propertyProvider == aksPropertyProvider:
-			klog.V(2).Info("setting up the AKS property provider")
+		case propertyProvider != nil && *propertyProvider == azurePropertyProvider:
+			klog.V(2).Info("setting up the Azure property provider")
 			// Note that the property provider, though initialized here, is not started until
 			// the specific instance wins the leader election.
-			pp = aks.New(region)
+			pp = azure.New(region)
 		default:
 			// Fall back to not using any property provider if the provided type is none or
 			// not recognizable.

docs/concepts/PropertyProviderAndClusterProperties/README.md

@@ -50,8 +50,8 @@ in the form of Kubernetes conditions.
 
 The Fleet member agent can run with or without a property provider. If a provider is not set up, or
 the given provider fails to start properly, the agent will collect limited properties about
-the cluster on its own, specifically the total and allocatable CPU and memory capacities of
-the host member cluster. 
+the cluster on its own, specifically the node count, plus the total/allocatable
+CPU and memory capacities of the host member cluster. 
 
 ## Cluster properties
 
@@ -75,7 +75,7 @@ such as `cpu` and `memory`, and the usage information should consist of:
 * Non-resource property: a metric about a member cluster, in the form of a key/value
 pair; the key should be in the format of
 [a Kubernetes label key](https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#syntax-and-character-set),
-such as `kubernetes.azure.com/node-count`, and the value at this moment should be a sortable
+such as `kubernetes-fleet.io/node-count`, and the value at this moment should be a sortable
 numeric that can be parsed as
 [a Kubernetes quantity](https://kubernetes.io/docs/reference/kubernetes-api/common-definitions/quantity/).
 
@@ -92,7 +92,7 @@ status:
   agentStatus: ...
   conditions: ...
   properties:
-    kubernetes.azure.com/node-count:
+    kubernetes-fleet.io/node-count:
       observationTime: "2024-04-30T14:54:24Z"
       value: "2"
     ...
@@ -111,3 +111,14 @@ status:
 Note that conditions reported by the property provider (if any), would be available in the
 `.status.conditions` array as well.
 
+### Core properties
+
+The following properties are considered core properties in Fleet, which should be supported
+in all property provider implementations. Fleet agents will collect them even when no
+property provider has been set up.
+
+| Property Type | Name | Description |
+| ------------- | ---- | ----------- |
+| Non-resource property | `kubernetes-fleet.io/node-count` | The number of nodes in a cluster. |
+| Resource property | `cpu` | The usage information (total, allocatable, and available capacity) of CPU resource in a cluster. |
+| Resource property | `memory` | The usage information (total, allocatable, and available capacity) of memory resource in a cluster. |

docs/howtos/property-based-scheduling.md

@@ -101,7 +101,7 @@ spec:
                 clusterSelectorTerms:
                 - propertySelector:
                     matchExpressions:
-                    - name: "kubernetes.azure.com/node-count"
+                    - name: "kubernetes-fleet.io/node-count"
                       operator: Ge
                       values:
                       - "5"
@@ -130,7 +130,7 @@ spec:
                       region: east
                   propertySelector:
                     matchExpressions:
-                    - name: "kubernetes.azure.com/node-count"
+                    - name: "kubernetes-fleet.io/node-count"
                       operator: Ge
                       values:
                       - "5"
@@ -225,7 +225,7 @@ spec:
             - weight: 20
               preference:
                 metricSorter:
-                  name: kubernetes.azure.com/node-count
+                  name: kubernetes-fleet.io/node-count
                   sortOrder: Descending
 ```
 

pkg/controllers/internalmembercluster/v1beta1/member_controller.go

@@ -463,6 +463,12 @@ func (r *Reconciler) updateResourceStats(ctx context.Context, imc *clusterv1beta
 		allocatableMemory.Add(*(node.Status.Allocatable.Memory()))
 	}
 
+	imc.Status.Properties = map[clusterv1beta1.PropertyName]clusterv1beta1.PropertyValue{
+		propertyprovider.NodeCountProperty: {
+			Value:           fmt.Sprintf("%d", len(nodes.Items)),
+			ObservationTime: metav1.Now(),
+		},
+	}
 	imc.Status.ResourceUsage.Capacity = corev1.ResourceList{
 		corev1.ResourceCPU:    capacityCPU,
 		corev1.ResourceMemory: capacityMemory,

pkg/controllers/internalmembercluster/v1beta1/member_controller_integration_test.go

@@ -18,6 +18,7 @@ import (
 
 	clusterv1beta1 "go.goms.io/fleet/apis/cluster/v1beta1"
 	"go.goms.io/fleet/pkg/controllers/work"
+	"go.goms.io/fleet/pkg/propertyprovider"
 	"go.goms.io/fleet/pkg/utils"
 )
 
@@ -136,6 +137,7 @@ var _ = Describe("Test Internal Member Cluster Controller", Serial, func() {
 			Expect(updatedHealthCond.Reason).To(Equal(EventReasonInternalMemberClusterHealthy))
 
 			By("checking updated member cluster usage")
+			Expect(imc.Status.Properties[propertyprovider.NodeCountProperty].Value).ShouldNot(BeEmpty())
 			Expect(imc.Status.ResourceUsage.Allocatable).ShouldNot(BeNil())
 			Expect(imc.Status.ResourceUsage.Capacity).ShouldNot(BeNil())
 			Expect(imc.Status.ResourceUsage.ObservationTime).ToNot(Equal(metav1.Now()))

pkg/propertyprovider/aks/controllers/node.go → pkg/propertyprovider/azure/controllers/node.go

@@ -4,7 +4,7 @@ Licensed under the MIT license.
 */
 
 // Package controllers feature a number of controllers that are in use
-// by the AKS property provider.
+// by the Azure property provider.
 package controllers
 
 import (
@@ -17,7 +17,7 @@ import (
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 
-	"go.goms.io/fleet/pkg/propertyprovider/aks/trackers"
+	"go.goms.io/fleet/pkg/propertyprovider/azure/trackers"
 )
 
 // NodeReconciler reconciles Node objects.
@@ -30,10 +30,10 @@ type NodeReconciler struct {
 func (r *NodeReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
 	nodeRef := klog.KRef(req.Namespace, req.Name)
 	startTime := time.Now()
-	klog.V(2).InfoS("Reconciliation starts for node objects in the AKS property provider", "node", nodeRef)
+	klog.V(2).InfoS("Reconciliation starts for node objects in the Azure property provider", "node", nodeRef)
 	defer func() {
 		latency := time.Since(startTime).Milliseconds()
-		klog.V(2).InfoS("Reconciliation ends for node objects in the AKS property provider", "node", nodeRef, "latency", latency)
+		klog.V(2).InfoS("Reconciliation ends for node objects in the Azure property provider", "node", nodeRef, "latency", latency)
 	}()
 
 	// Retrieve the node object.

pkg/propertyprovider/aks/controllers/pod.go → pkg/propertyprovider/azure/controllers/pod.go

@@ -4,7 +4,7 @@ Licensed under the MIT license.
 */
 
 // Package controllers feature a number of controllers that are in use
-// by the AKS property provider.
+// by the Azure property provider.
 package controllers
 
 import (
@@ -17,7 +17,7 @@ import (
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 
-	"go.goms.io/fleet/pkg/propertyprovider/aks/trackers"
+	"go.goms.io/fleet/pkg/propertyprovider/azure/trackers"
 )
 
 // TO-DO (chenyu1): this is a relatively expensive watcher, due to how frequent pods can change
@@ -35,10 +35,10 @@ type PodReconciler struct {
 func (p *PodReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
 	podRef := klog.KRef(req.Namespace, req.Name)
 	startTime := time.Now()
-	klog.V(2).InfoS("Reconciliation starts for pod objects in the AKS property provider", "pod", podRef)
+	klog.V(2).InfoS("Reconciliation starts for pod objects in the Azure property provider", "pod", podRef)
 	defer func() {
 		latency := time.Since(startTime).Milliseconds()
-		klog.V(2).InfoS("Reconciliation ends for pod objects in the AKS property provider", "pod", podRef, "latency", latency)
+		klog.V(2).InfoS("Reconciliation ends for pod objects in the Azure property provider", "pod", podRef, "latency", latency)
 	}()
 
 	// Retrieve the pod object.