*: refactor meta metrics

move meta metrics under the `metrics` package.

pkg/manifests/config.go

@@ -31,6 +31,8 @@ import (
 	k8syaml "k8s.io/apimachinery/pkg/util/yaml"
 	auditv1 "k8s.io/apiserver/pkg/apis/audit/v1"
 	"k8s.io/klog/v2"
+
+	"github.com/openshift/cluster-monitoring-operator/pkg/metrics"
 )
 
 const (

pkg/metrics/metrics.go

@@ -0,0 +1,27 @@
+package metrics
+
+import (
+	"k8s.io/component-base/metrics"
+	"k8s.io/component-base/metrics/legacyregistry"
+)
+
+// ReconcileAttempts is a counter that indicates the number of attempts to reconcile the operator configuration.
+var ReconcileAttempts = metrics.NewCounter(&metrics.CounterOpts{
+	Name:           "cluster_monitoring_operator_reconcile_attempts_total",
+	Help:           "Number of attempts to reconcile the operator configuration.",
+	StabilityLevel: metrics.ALPHA,
+})
+
+// ReconcileStatus is a gauge that indicates the latest reconciliation state.
+var ReconcileStatus = metrics.NewGauge(&metrics.GaugeOpts{
+	Name:           "cluster_monitoring_operator_last_reconciliation_successful",
+	Help:           "Latest reconciliation state. Set to 1 if last reconciliation succeeded, else 0.",
+	StabilityLevel: metrics.ALPHA,
+})
+
+func init() {
+	// The API (metrics) server is instrumented to work with component-base.
+	// Refer: https://github.com/kubernetes/kubernetes/blob/ec87834bae787ab6687921d65c3bcfde8a6e01b9/staging/src/k8s.io/apiserver/pkg/server/routes/metrics.go#L44.
+	legacyregistry.MustRegister(ReconcileAttempts)
+	legacyregistry.MustRegister(ReconcileStatus)
+}

pkg/operator/operator.go

@@ -22,15 +22,15 @@ import (
 	"time"
 
 	"github.com/blang/semver/v4"
-	"github.com/openshift/cluster-monitoring-operator/pkg/alert"
-	"github.com/openshift/cluster-monitoring-operator/pkg/rebalancer"
-	cmostr "github.com/openshift/cluster-monitoring-operator/pkg/strings"
 	"github.com/pkg/errors"
 	certapiv1 "k8s.io/api/certificates/v1"
 	v1 "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
-	"k8s.io/component-base/metrics"
-	"k8s.io/component-base/metrics/legacyregistry"
+
+	"github.com/openshift/cluster-monitoring-operator/pkg/alert"
+	"github.com/openshift/cluster-monitoring-operator/pkg/metrics"
+	"github.com/openshift/cluster-monitoring-operator/pkg/rebalancer"
+	cmostr "github.com/openshift/cluster-monitoring-operator/pkg/strings"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	k8sruntime "k8s.io/apimachinery/pkg/runtime"
@@ -183,9 +183,6 @@ type Operator struct {
 
 	queue workqueue.RateLimitingInterface
 
-	reconcileAttempts *metrics.Counter
-	reconcileStatus   *metrics.Gauge
-
 	failedReconcileAttempts int
 
 	assets *manifests.Assets
@@ -254,22 +251,7 @@ func New(
 		rebalancer:                rebalancer.NewRebalancer(ctx, c.KubernetesInterface()),
 		ruleController:            ruleController,
 		relabelController:         relabelController,
-		reconcileAttempts: metrics.NewCounter(&metrics.CounterOpts{
-			Name:           "cluster_monitoring_operator_reconcile_attempts_total",
-			Help:           "Number of attempts to reconcile the operator configuration",
-			StabilityLevel: metrics.ALPHA,
-		}),
-		reconcileStatus: metrics.NewGauge(&metrics.GaugeOpts{
-			Name:           "cluster_monitoring_operator_last_reconciliation_successful",
-			Help:           "Latest reconciliation state. Set to 1 if last reconciliation succeeded, else 0.",
-			StabilityLevel: metrics.ALPHA,
-		}),
-	}
-
-	legacyregistry.MustRegister(
-		o.reconcileAttempts,
-		o.reconcileStatus,
-	)
+	}
 
 	informer := cache.NewSharedIndexInformer(
 		o.client.SecretListWatchForNamespace(namespace), &v1.Secret{}, resyncPeriod, cache.Indexers{},
@@ -650,15 +632,15 @@ func (o *Operator) processNextWorkItem(ctx context.Context) bool {
 	}
 	defer o.queue.Done(key)
 
-	o.reconcileAttempts.Inc()
+	metrics.ReconcileAttempts.Inc()
 	err := o.sync(ctx, key.(string))
 	if err == nil {
-		o.reconcileStatus.Set(1)
+		metrics.ReconcileStatus.Set(1)
 		o.queue.Forget(key)
 		return true
 	}
 
-	o.reconcileStatus.Set(0)
+	metrics.ReconcileStatus.Set(0)
 	klog.Errorf("Syncing %q failed", key)
 	utilruntime.HandleError(errors.Wrapf(err, "sync %q failed", key))
 	o.queue.AddRateLimited(key)