func()

in clusterloader2/pkg/imagepreload/imagepreload.go [85:160]

• 68 lines of code
• 12 McCabe index (conditional complexity)

func (c *controller) PreloadImages() error {
	if len(images) == 0 {
		klog.Warning("No images specified. Skipping image preloading")
		return nil
	}
	if !c.config.ClusterConfig.Provider.Features().SupportImagePreload {
		klog.Warningf("Image preloading is disabled in provider: %s", c.config.ClusterConfig.Provider.Name())
		return nil
	}

	kclient := c.framework.GetClientSets().GetClient()

	doneNodes := make(map[string]struct{})
	stopCh := make(chan struct{})
	defer close(stopCh)

	nodeInformer := informer.NewInformer(
		&cache.ListWatch{
			ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
				return kclient.CoreV1().Nodes().List(context.TODO(), options)
			},
			WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
				return kclient.CoreV1().Nodes().Watch(context.TODO(), options)
			},
		},
		func(old, new interface{}) { c.checkNode(doneNodes, old, new) })
	if err := informer.StartAndSync(nodeInformer, stopCh, informerTimeout); err != nil {
		return err
	}

	klog.V(2).Infof("Creating namespace %s...", namespace)
	if err := client.CreateNamespace(kclient, namespace); err != nil {
		return err
	}

	klog.V(2).Info("Creating daemonset to preload images...")
	c.templateMapping["Images"] = c.images
	if err := c.framework.ApplyTemplatedManifests(manifest, c.templateMapping); err != nil {
		return err
	}

	klog.V(2).Infof("Getting %s/%s deamonset size...", namespace, daemonsetName)
	ds, err := kclient.AppsV1().DaemonSets(namespace).Get(context.TODO(), daemonsetName, metav1.GetOptions{})
	if err != nil {
		return err
	}
	size, err := runtimeobjects.GetReplicasFromRuntimeObject(kclient, ds)
	if err != nil {
		return err
	}
	if err := size.Start(stopCh); err != nil {
		return err
	}

	var clusterSize, doneCount int
	klog.V(2).Infof("Waiting for %d Node objects to be updated...", size.Replicas())
	if err := wait.Poll(pollingInterval, pollingTimeout, func() (bool, error) {
		clusterSize = size.Replicas()
		doneCount = c.countDone(doneNodes)
		klog.V(3).Infof("%d out of %d nodes have pulled images", doneCount, clusterSize)
		return doneCount == clusterSize, nil
	}); err != nil {
		klog.Errorf("%d out of %d nodes have pulled images", doneCount, clusterSize)
		return err
	}
	klog.V(2).Info("Waiting... done")

	klog.V(2).Infof("Deleting namespace %s...", namespace)
	if err := client.DeleteNamespace(kclient, namespace); err != nil {
		return err
	}
	if err := client.WaitForDeleteNamespace(kclient, namespace); err != nil {
		return err
	}
	return nil
}