func StartPodCacheWatch()

in pkg/exporter/nettop/k8s.go [347:418]
61 lines of code
6 McCabe index (conditional complexity)

func StartPodCacheWatch(ctx context.Context) (*PodCache, error) {
	nodeName := os.Getenv("INSPECTOR_NODENAME")
	if nodeName == "" {
		return nil, fmt.Errorf("INSPECTOR_NODENAME environment variable not set")
	}
	log.SetLogger(textlogger.NewLogger(textlogger.NewConfig()))

	podCache := NewPodCache()

	// Initialize cgroup watcher
	podCache.initCgroupWatch()

	scheme := runtime.NewScheme()
	utilruntime.Must(v1.AddToScheme(scheme))
	// Create manager
	mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrl.Options{
		MetricsBindAddress: "0",
		Cache: cache.Options{
			Scheme: scheme,
			ByObject: map[client.Object]cache.ByObject{
				&v1.Pod{}: {
					Field: client.MatchingFieldsSelector{
						Selector: fields.SelectorFromSet(fields.Set{"spec.nodeName": nodeName}),
					},
					Transform: func(i interface{}) (interface{}, error) {
						if pod, ok := i.(*v1.Pod); ok {
							pod.Spec.Volumes = nil
							pod.Spec.EphemeralContainers = nil
							pod.Spec.SecurityContext = nil
							pod.Spec.ImagePullSecrets = nil
							pod.Spec.Tolerations = nil
							pod.Spec.ReadinessGates = nil
							pod.Spec.PreemptionPolicy = nil
							pod.Status.InitContainerStatuses = nil
							pod.Status.ContainerStatuses = nil
							pod.Status.EphemeralContainerStatuses = nil
							return pod, nil
						}
						return nil, fmt.Errorf("unexpected type %T", i)
					},
				},
			},
		},
	})
	if err != nil {
		return nil, fmt.Errorf("unable to create manager: %v", err)
	}

	controller := &PodReconciler{PodCache: podCache, Client: mgr.GetClient()}
	// Create pod controller
	err = ctrl.NewControllerManagedBy(mgr).
		For(&v1.Pod{}).
		WithEventFilter(predicate.NewPredicateFuncs(func(object client.Object) bool {
			pod := object.(*v1.Pod)
			return pod.Spec.NodeName == nodeName
		})).
		Complete(controller)
	if err != nil {
		return nil, fmt.Errorf("unable to create controller: %v", err)
	}

	// Start manager
	go func() {
		if err := mgr.Start(ctx); err != nil {
			klog.Errorf("Failed to start manager: %v", err)
		}
	}()

	go controller.GC(ctx)

	return podCache, nil
}