added metrics for subnamespaces

With this PR, there are now metrics showing for each subnamespace
the quantities of the resources it has.

Signed-off-by: mzeevi <meytar80@gmail.com>

cmd/main.go

@@ -18,6 +18,8 @@ import (
 	"flag"
 	"os"
 
+	"github.com/dana-team/hns/internal/metrics"
+
 	userv1 "github.com/openshift/api/user/v1"
 
 	danav1 "github.com/dana-team/hns/api/v1"
@@ -108,6 +110,9 @@ func main() {
 	}
 	// +kubebuilder:scaffold:builder
 
+	// Register the HNS specific metrics
+	metrics.InitializeHNSMetrics()
+
 	setupLog.Info("starting manager")
 	if err := mgr.Start(ctrl.SetupSignalHandler()); err != nil {
 		setupLog.Error(err, "problem running manager")

internal/metrics/metrics.go

@@ -0,0 +1,69 @@
+package metrics
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"sigs.k8s.io/controller-runtime/pkg/metrics"
+)
+
+// InitializeHNSMetrics registers the relevant metrics.
+func InitializeHNSMetrics() {
+	metrics.Registry.MustRegister(
+		snsAllocatedResources,
+		snsFreeResources,
+		snsTotalResources,
+	)
+}
+
+var (
+	snsAllocatedResources = prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "sns_allocated_resources",
+			Help: "Indication of the quantity of an allocated subnamespace resource",
+		}, []string{"name", "namespace", "resource"},
+	)
+)
+
+var (
+	snsFreeResources = prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "sns_free_resources",
+			Help: "Indication of the quantity of a free subnamespace resource",
+		}, []string{"name", "namespace", "resource"},
+	)
+)
+
+var (
+	snsTotalResources = prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "sns_total_resources",
+			Help: "Indication of the total quantity of a subnamespace resource",
+		}, []string{"name", "namespace", "resource"},
+	)
+)
+
+// ObserveSNSAllocatedResource sets the allocated metric as per the quantity.
+func ObserveSNSAllocatedResource(name, namespace, resource string, quantity float64) {
+	snsAllocatedResources.With(prometheus.Labels{
+		"name":      name,
+		"namespace": namespace,
+		"resource":  resource,
+	}).Set(quantity)
+}
+
+// ObserveSNSFreeResource sets the allocatable metric as per the quantity.
+func ObserveSNSFreeResource(name, namespace, resource string, quantity float64) {
+	snsFreeResources.With(prometheus.Labels{
+		"name":      name,
+		"namespace": namespace,
+		"resource":  resource,
+	}).Set(quantity)
+}
+
+// ObserveSNSTotalResource sets the total metric as per the quantity.
+func ObserveSNSTotalResource(name, namespace, resource string, quantity float64) {
+	snsTotalResources.With(prometheus.Labels{
+		"name":      name,
+		"namespace": namespace,
+		"resource":  resource,
+	}).Set(quantity)
+}

internal/subnamespace/sync.go

@@ -3,6 +3,8 @@ package subnamespace
 import (
 	"fmt"
 
+	"github.com/dana-team/hns/internal/metrics"
+
 	danav1 "github.com/dana-team/hns/api/v1"
 	"github.com/dana-team/hns/internal/namespace/nsutils"
 	"github.com/dana-team/hns/internal/namespacedb"
@@ -138,6 +140,9 @@ func (r *SubnamespaceReconciler) sync(snsParentNS, snsObject *objectcontext.Obje
 	}
 	logger.Info("successfully set status for subnamespace", "subnamespace", snsName)
 
+	updateSNSMetrics(snsName, snsParentName, free, resourceAllocatedToChildren, snsObject.Object.(*danav1.Subnamespace).Spec.ResourceQuotaSpec.Hard)
+	logger.Info("successfully set metrics for subnamespace", "subnamespace", snsName)
+
 	// trigger reconciliation for parent subnamespace so that it can be aware of
 	// potential changes in one of its children
 	r.enqueueSNSEvent(parentSNS.Name(), parentSNS.Object.GetNamespace())
@@ -389,10 +394,10 @@ func (r *SubnamespaceReconciler) enqueueChildrenSNSToRPConversionEvents(snsObjec
 
 // IsUpdateNeeded gets a subnamespace object, a []danav1.Namespaces and two resource lists and returns whether
 // the subnamespace object status has to be updated.
-func IsUpdateNeeded(subspace client.Object, childrenRequests []danav1.Namespaces, allocated, free corev1.ResourceList) bool {
-	if !NamespacesEqual(subspace.(*danav1.Subnamespace).Status.Namespaces, childrenRequests) ||
-		!quota.ResourceListEqual(subspace.(*danav1.Subnamespace).Status.Total.Allocated, allocated) ||
-		!quota.ResourceListEqual(subspace.(*danav1.Subnamespace).Status.Total.Free, free) {
+func IsUpdateNeeded(sns client.Object, childrenRequests []danav1.Namespaces, allocated, free corev1.ResourceList) bool {
+	if !NamespacesEqual(sns.(*danav1.Subnamespace).Status.Namespaces, childrenRequests) ||
+		!quota.ResourceListEqual(sns.(*danav1.Subnamespace).Status.Total.Allocated, allocated) ||
+		!quota.ResourceListEqual(sns.(*danav1.Subnamespace).Status.Total.Free, free) {
 		return true
 	}
 	return false
@@ -410,3 +415,16 @@ func NamespacesEqual(nsA, nsB []danav1.Namespaces) bool {
 	}
 	return true
 }
+
+// updateSNSMetrics updates the metrics for the subnamespace.
+func updateSNSMetrics(snsName, snsNS string, allocated, free, total corev1.ResourceList) {
+	for resourceName := range total {
+		allocatedResource := allocated[resourceName]
+		freeResource := free[resourceName]
+		totalResource := total[resourceName]
+
+		metrics.ObserveSNSAllocatedResource(snsName, snsNS, resourceName.String(), allocatedResource.AsApproximateFloat64())
+		metrics.ObserveSNSFreeResource(snsName, snsNS, resourceName.String(), freeResource.AsApproximateFloat64())
+		metrics.ObserveSNSTotalResource(snsName, snsNS, resourceName.String(), totalResource.AsApproximateFloat64())
+	}
+}