Add telemetry job - option 1

internal/mode/static/leader_runnable.go

@@ -0,0 +1,30 @@
+package static
+
+import (
+	"context"
+
+	"sigs.k8s.io/controller-runtime/pkg/manager"
+)
+
+type leaderOnlyRunnable struct {
+	electedCh chan struct{}
+	runnable  manager.Runnable
+}
+
+func newLeaderOnlyRunnable(electedCh chan struct{}, runnable manager.Runnable) *leaderOnlyRunnable {
+	return &leaderOnlyRunnable{
+		electedCh: electedCh,
+		runnable:  runnable,
+	}
+}
+
+func (l *leaderOnlyRunnable) Start(ctx context.Context) error {
+	select {
+	case <-ctx.Done():
+		return nil
+	case <-l.electedCh:
+		break
+	}
+
+	return l.runnable.Start(ctx)
+}

internal/mode/static/manager.go

@@ -45,6 +45,7 @@ import (
 	"github.com/nginxinc/nginx-gateway-fabric/internal/mode/static/state/relationship"
 	"github.com/nginxinc/nginx-gateway-fabric/internal/mode/static/state/resolver"
 	"github.com/nginxinc/nginx-gateway-fabric/internal/mode/static/state/validation"
+	"github.com/nginxinc/nginx-gateway-fabric/internal/mode/static/telemetry"
 )
 
 const (
@@ -63,6 +64,8 @@ func init() {
 	utilruntime.Must(apiext.AddToScheme(scheme))
 }
 
+// StartManager starts the controller manager.
+// nolint: gocyclo
 func StartManager(cfg config.Config) error {
 	options := manager.Options{
 		Scheme:  scheme,
@@ -205,12 +208,15 @@ func StartManager(cfg config.Config) error {
 
 	leaderElectorLogger := cfg.Logger.WithName("leaderElector")
 
+	electedCh := make(chan struct{})
+
 	if cfg.LeaderElection.Enabled {
 		leaderElector, err := newLeaderElectorRunnable(leaderElectorRunnableConfig{
 			kubeConfig: clusterCfg,
 			recorder:   recorder,
 			onStartedLeading: func(ctx context.Context) {
 				leaderElectorLogger.Info("Started leading")
+				close(electedCh)
 				statusUpdater.Enable(ctx)
 			},
 			onStoppedLeading: func() {
@@ -228,6 +234,19 @@ func StartManager(cfg config.Config) error {
 		if err = mgr.Add(leaderElector); err != nil {
 			return fmt.Errorf("cannot register leader elector: %w", err)
 		}
+	} else {
+		close(electedCh)
+	}
+
+	telemetryJob := newLeaderOnlyRunnable(
+		electedCh,
+		telemetry.NewJob(
+			&telemetry.StdoutExporter{},
+			cfg.Logger.WithName("telemetryExporter"),
+		),
+	)
+	if err = mgr.Add(telemetryJob); err != nil {
+		return fmt.Errorf("cannot register telemetry job: %w", err)
 	}
 
 	cfg.Logger.Info("Starting manager")

internal/mode/static/telemetry/job.go

@@ -0,0 +1,52 @@
+package telemetry
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/go-logr/logr"
+	"k8s.io/apimachinery/pkg/util/wait"
+)
+
+// Data type (any or not) is yet to be determined
+type Exporter interface {
+	Export(ctx context.Context, data any) error
+}
+
+type StdoutExporter struct{}
+
+func (s *StdoutExporter) Export(_ context.Context, data any) error {
+	fmt.Printf("exporting data: %+v\n", data)
+	return nil
+}
+
+type Data struct{}
+
+type Job struct {
+	exporter Exporter
+	logger   logr.Logger
+}
+
+func NewJob(exporter Exporter, logger logr.Logger) *Job {
+	return &Job{
+		exporter: exporter,
+		logger:   logger,
+	}
+}
+
+func (j *Job) Start(ctx context.Context) error {
+	j.logger.Info("starting telemetry job")
+	wait.UntilWithContext(ctx, j.report, 10*time.Second)
+	j.logger.Info("stopping telemetry job")
+	return nil
+}
+
+func (j *Job) report(ctx context.Context) {
+	j.logger.Info("reporting telemetry")
+
+	err := j.exporter.Export(ctx, Data{})
+	if err != nil {
+		j.logger.Error(err, "failed to export telemetry")
+	}
+}