func main()

in cmd/mcs-controller-manager/main.go [78:188]
92 lines of code
12 McCabe index (conditional complexity)

func main() {
	flag.Parse()
	rand.Seed(time.Now().UnixNano())

	handleExitFunc := func() {
		klog.Flush()
	}

	exitWithErrorFunc := func() {
		handleExitFunc()
		os.Exit(1)
	}

	defer handleExitFunc()

	flag.VisitAll(func(f *flag.Flag) {
		klog.InfoS("flag:", "name", f.Name, "value", f.Value)
	})

	// Set up controller-runtime logger
	ctrl.SetLogger(zap.New(zap.UseDevMode(true)))

	memberConfig, memberOptions := prepareMemberParameters()

	hubConfig, hubOptions, err := prepareHubParameters(memberConfig)
	if err != nil {
		exitWithErrorFunc()
	}

	// Setup hub controller manager.
	hubMgr, err := ctrl.NewManager(hubConfig, *hubOptions)
	if err != nil {
		klog.ErrorS(err, "Unable to start hub manager")
		exitWithErrorFunc()
	}
	if err := hubMgr.AddHealthzCheck("healthz", healthz.Ping); err != nil {
		klog.ErrorS(err, "Unable to set up health check for hub manager")
		exitWithErrorFunc()
	}
	if err := hubMgr.AddReadyzCheck("readyz", healthz.Ping); err != nil {
		klog.ErrorS(err, "Unable to set up ready check for hub manager")
		exitWithErrorFunc()
	}

	// Setup member controller manager.
	memberMgr, err := ctrl.NewManager(memberConfig, *memberOptions)
	if err != nil {
		klog.ErrorS(err, "Unable to start member manager")
		exitWithErrorFunc()
	}
	if err := memberMgr.AddHealthzCheck("healthz", healthz.Ping); err != nil {
		klog.ErrorS(err, "Unable to set up health check for member manager")
		exitWithErrorFunc()
	}
	if err := memberMgr.AddReadyzCheck("readyz", healthz.Ping); err != nil {
		klog.ErrorS(err, "Unable to set up ready check for member manager")
		exitWithErrorFunc()
	}

	ctx, cancel := context.WithCancel(context.Background())

	klog.V(1).InfoS("Setup controllers with controller manager")
	if err := setupControllersWithManager(ctx, hubMgr, memberMgr); err != nil {
		klog.ErrorS(err, "Unable to setup controllers with manager")
		exitWithErrorFunc()
	}

	// All managers should stop if either of them is dead or Linux SIGTERM or SIGINT signal is received
	ch := make(chan os.Signal, 1)
	signal.Notify(ch, os.Interrupt, syscall.SIGTERM)
	go func() {
		<-ch
		klog.Info("Received termination, signaling shutdown MultiClusterService agent")
		cancel()
	}()

	var startErrors []error
	wg := &sync.WaitGroup{}
	wg.Add(1)
	go func() {
		klog.V(1).InfoS("Starting hub manager for MultiClusterService agent")
		defer func() {
			wg.Done()
			klog.V(1).InfoS("Shutting down hub manager")
			cancel()
		}()
		if err := hubMgr.Start(ctx); err != nil {
			klog.ErrorS(err, "Failed to start hub manager")
			startErrors = append(startErrors, err)
		}
	}()
	wg.Add(1)
	go func() {
		klog.V(1).InfoS("Starting member manager for MultiClusterService agent")
		defer func() {
			klog.V(1).InfoS("Shutting down member manager")
			wg.Done()
			cancel()
		}()
		if err = memberMgr.Start(ctx); err != nil {
			klog.ErrorS(err, "Failed to start member manager")
			startErrors = append(startErrors, err)
		}
	}()

	wg.Wait()

	if len(startErrors) > 0 {
		exitWithErrorFunc()
	}
}