Provide scale-set listener metrics (#2559)

Co-authored-by: Tingluo Huang <tingluohuang@github.com>
Co-authored-by: Bassem Dghaidi <568794+Link-@users.noreply.github.com>

controllers/actions.github.com/ephemeralrunnerset_controller.go

@@ -25,6 +25,7 @@ import (
 	"strings"
 
 	"github.com/actions/actions-runner-controller/apis/actions.github.com/v1alpha1"
+	"github.com/actions/actions-runner-controller/controllers/actions.github.com/metrics"
 	"github.com/actions/actions-runner-controller/github/actions"
 	"github.com/go-logr/logr"
 	"go.uber.org/multierr"
@@ -50,6 +51,8 @@ type EphemeralRunnerSetReconciler struct {
 	Scheme        *runtime.Scheme
 	ActionsClient actions.MultiClient
 
+	PublishMetrics bool
+
 	resourceBuilder resourceBuilder
 }
 
@@ -163,6 +166,29 @@ func (r *EphemeralRunnerSetReconciler) Reconcile(ctx context.Context, req ctrl.R
 		"deleting", len(deletingEphemeralRunners),
 	)
 
+	if r.PublishMetrics {
+		githubConfigURL := ephemeralRunnerSet.Spec.EphemeralRunnerSpec.GitHubConfigUrl
+		parsedURL, err := actions.ParseGitHubConfigFromURL(githubConfigURL)
+		if err != nil {
+			log.Error(err, "Github Config URL is invalid", "URL", githubConfigURL)
+			// stop reconciling on this object
+			return ctrl.Result{}, nil
+		}
+
+		metrics.SetEphemeralRunnerCountsByStatus(
+			metrics.CommonLabels{
+				Name:         ephemeralRunnerSet.Labels[LabelKeyGitHubScaleSetName],
+				Namespace:    ephemeralRunnerSet.Labels[LabelKeyGitHubScaleSetNamespace],
+				Repository:   parsedURL.Repository,
+				Organization: parsedURL.Organization,
+				Enterprise:   parsedURL.Enterprise,
+			},
+			len(pendingEphemeralRunners),
+			len(runningEphemeralRunners),
+			len(failedEphemeralRunners),
+		)
+	}
+
 	// cleanup finished runners and proceed
 	var errs []error
 	for i := range finishedEphemeralRunners {