feat(rrset): Add custom metrics (#45)

Signed-off-by: Anthony TREUILLIER <anthony.treuillier.ext@orange.com>

Author: antrema

config/default/kustomization.yaml

@@ -24,7 +24,7 @@ resources:
 # [CERTMANAGER] To enable cert-manager, uncomment all sections with 'CERTMANAGER'. 'WEBHOOK' components are required.
 #- ../certmanager
 # [PROMETHEUS] To enable prometheus monitor, uncomment all sections with 'PROMETHEUS'.
-#- ../prometheus
+- ../prometheus
 
 patches:
   - path: manager_env_patch.yaml

go.mod

@@ -6,6 +6,7 @@ require (
 	github.com/joeig/go-powerdns/v3 v3.14.1
 	github.com/onsi/ginkgo/v2 v2.20.0
 	github.com/onsi/gomega v1.34.1
+	github.com/prometheus/client_golang v1.20.0
 	k8s.io/apimachinery v0.31.0
 	k8s.io/client-go v0.31.0
 	k8s.io/utils v0.0.0-20240711033017-18e509b52bc8
@@ -38,12 +39,12 @@ require (
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/compress v1.17.9 // indirect
+	github.com/kylelemons/godebug v1.1.0 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
-	github.com/prometheus/client_golang v1.20.0 // indirect
 	github.com/prometheus/client_model v0.6.1 // indirect
 	github.com/prometheus/common v0.55.0 // indirect
 	github.com/prometheus/procfs v0.15.1 // indirect

internal/controller/pdns_metrics.go

@@ -0,0 +1,49 @@
+package controller
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/testutil"
+)
+
+var (
+	rrsetsStatusesMetric = prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "rrsets_status",
+			Help: "Statuses of RRsets processed",
+		},
+		[]string{"fqdn", "type", "status", "name", "namespace"},
+	)
+)
+
+func updateRrsetsMetrics(fqdn, rrsetType, rrsetStatus, name, namespace string) {
+	rrsetsStatusesMetric.With(map[string]string{
+		"fqdn":      fqdn,
+		"type":      rrsetType,
+		"status":    rrsetStatus,
+		"name":      name,
+		"namespace": namespace,
+	}).Set(1)
+}
+func removeRrsetMetrics(name, namespace string) {
+	rrsetsStatusesMetric.DeletePartialMatch(
+		map[string]string{
+			"namespace": namespace,
+			"name":      name,
+		},
+	)
+}
+
+//nolint:unparam
+func getMetricWithLabels(rrsetFQDN, rrsetType, rrsetStatus, rrsetName, rrsetNamespace string) float64 {
+	return testutil.ToFloat64(rrsetsStatusesMetric.With(prometheus.Labels{
+		"fqdn":      rrsetFQDN,
+		"type":      rrsetType,
+		"status":    rrsetStatus,
+		"name":      rrsetName,
+		"namespace": rrsetNamespace,
+	}))
+}
+
+func countMetrics() int {
+	return testutil.CollectAndCount(rrsetsStatusesMetric)
+}

internal/controller/rrset_controller.go

@@ -24,6 +24,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
 	"sigs.k8s.io/controller-runtime/pkg/log"
+	"sigs.k8s.io/controller-runtime/pkg/metrics"
 
 	dnsv1alpha1 "github.com/orange-opensource/powerdns-operator/api/v1alpha1"
 )
@@ -40,6 +41,11 @@ type RRsetReconciler struct {
 	PDNSClient PdnsClienter
 }
 
+func init() {
+	// Register custom metrics with the global prometheus registry
+	metrics.Registry.MustRegister(rrsetsStatusesMetric)
+}
+
 // +kubebuilder:rbac:groups=dns.cav.enablers.ob,resources=rrsets,verbs=get;list;watch;create;update;patch;delete
 // +kubebuilder:rbac:groups=dns.cav.enablers.ob,resources=rrsets/status,verbs=get;update;patch
 // +kubebuilder:rbac:groups=dns.cav.enablers.ob,resources=rrsets/finalizers,verbs=update
@@ -77,6 +83,8 @@ func (r *RRsetReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl
 					log.Error(err, "Failed to remove finalizer")
 					return ctrl.Result{}, err
 				}
+				// Remove resource metrics
+				removeRrsetMetrics(rrset.Name, rrset.Namespace)
 			}
 			// Race condition when creating Zone+RRset at the same time
 			// RRset is not created because Zone is not created yet
@@ -119,6 +127,9 @@ func (r *RRsetReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl
 				log.Error(err, "Failed to remove finalizer")
 				return ctrl.Result{}, err
 			}
+			// Remove resource metrics
+			removeRrsetMetrics(rrset.Name, rrset.Namespace)
+
 			//nolint:ineffassign
 			lastUpdateTime = &metav1.Time{Time: time.Now().UTC()}
 		}
@@ -129,6 +140,9 @@ func (r *RRsetReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl
 
 	// We cannot exit previously (at the early moments of reconcile), because we have to allow deletion process
 	if isInFailedStatus {
+		// Update resource metrics
+		updateRrsetsMetrics(getRRsetName(rrset), rrset.Spec.Type, *rrset.Status.SyncStatus, rrset.Name, rrset.Namespace)
+
 		return ctrl.Result{}, nil
 	}
 
@@ -151,6 +165,10 @@ func (r *RRsetReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl
 			log.Error(err, "unable to patch RRSet status")
 			return ctrl.Result{}, err
 		}
+
+		// Update resource metrics
+		updateRrsetsMetrics(getRRsetName(rrset), rrset.Spec.Type, *rrset.Status.SyncStatus, rrset.Name, rrset.Namespace)
+
 		return ctrl.Result{}, nil
 	}
 
@@ -195,6 +213,9 @@ func (r *RRsetReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl
 		return ctrl.Result{}, err
 	}
 
+	// Metrics calculation
+	updateRrsetsMetrics(getRRsetName(rrset), rrset.Spec.Type, *rrset.Status.SyncStatus, rrset.Name, rrset.Namespace)
+
 	return ctrl.Result{}, nil
 }