通过Informer界面查看Kubernetes Pod、Namespace和Node状态

Question

有一种方法可以设置对K8s pod状态的监视，我可以测试其功能。

然后，podWatchController接收事件，并调用相应的处理程序。但是，此机制不适用于命名空间和节点，即NewListWatchFromClient构造函数中不存在这些选项。

请建议如何使用此模式查看Node和Namespace状态(添加、删除、更新)。

    podWatchlist := cache.NewListWatchFromClient(
       k8s.kubeClient.K8sClient.CoreV1().RESTClient(),
       string(v1.ResourcePods),
       v1.NamespaceAll,
       fields.Everything(),
    )

    // K8s Pod watcher controller
    _, podWatchController := cache.NewInformer( // also take a look at NewSharedIndexInformer
       podWatchlist,
       &v1.Pod{},
       0, //Duration is int64
       cache.ResourceEventHandlerFuncs{
           AddFunc: func(obj interface{}) {
               k8s.handleAddPod(obj)
           },
           DeleteFunc: func(obj interface{}) {
               k8s.handleDeletePod(obj)
           },
           UpdateFunc: func(oldObj, newObj interface{}) {
               k8s.handleUpdatePod(oldObj, newObj)
           },
       },
    )

    podStopChan := make(chan struct{})
    go podWatchController.Run(podStopChan)

我发现了另一种基于NewSharedInformerFactory的方法，它为pods、节点和名称空间提供了监视器；但是，我没有看到处理程序收到任何通知。这种方法可能会遗漏什么？

对于Pod：

    // Add watcher for the Pod.
    factory := informers.NewSharedInformerFactory(k8s.kubeClient.K8sClient, 0)
    podInformer := factory.Core().V1().Pods().Informer()
    podInformerChan := make(chan struct{})
    defer close(podInformerChan)

    // Pod informer state change handler
    podInformer.AddEventHandler(cache.ResourceEventHandlerFuncs{
        // When a new pod gets created
        AddFunc: func(obj interface{}) {
            k8s.handleAddPod(obj)
        },
        // When a pod gets updated
        UpdateFunc: func(oldObj interface{}, newObj interface{}) {
            k8s.handleUpdatePod(oldObj, newObj)
        },
        // When a pod gets deleted
        DeleteFunc: func(obj interface{}) {
            k8s.handleDeletePod(obj)
        },
    })

    go podInformer.GetController().Run(podInformerChan)

对于命名空间：

    // Add watcher for the Namespace.
    factory := informers.NewSharedInformerFactory(k8s.kubeClient.K8sClient, 0)
    nsInformer := factory.Core().V1().Namespaces().Informer()
    nsInformerChan := make(chan struct{})
    defer close(nsInformerChan)

    // Namespace informer state change handler
    nsInformer.AddEventHandler(cache.ResourceEventHandlerFuncs {
       // When a new namespace gets created
       AddFunc:    func(obj interface{}) {
           k8s.handleAddNamespace(obj)
       },
       // When a namespace gets updated
       UpdateFunc: func(oldObj interface{}, newObj interface{}) {
           k8s.handleUpdateNamespace(obj)
       },
       // When a namespace gets deleted
       DeleteFunc: func(obj interface{}) {
           k8s.handleDeleteNamespace(obj)
       },
    })
    go nsInformer.GetController().Run(nsInformerChan)

Answer 1

我可以通过以下更改让它工作，即我们必须调用工厂、通知程序和控制器的Run()方法。

sharedInformer.Start(podInformerChan)

podInformer.Run(podInformerChan)
podInformer.GetController().Run(podInformerChan)
nsInformer.Run(nsInformerChan)
nsInformer.GetController().Run(nsInformerChan)

然而，仍然有一些错误显示并试图理解它们是什么。目前，他们正指向这条线。

https://github.com/kubernetes/client-go/blob/master/tools/cache/shared_informer.go#L612

E0809 15:33:39.187411   79537 shared_informer.go:611] unrecognized notification: <nil>
E0809 15:33:40.191304   79537 shared_informer.go:611] unrecognized notification: <nil>
E0809 15:33:48.227933   79537 shared_informer.go:611] unrecognized notification: <nil>
E0809 15:33:54.231458   79537 shared_informer.go:611] unrecognized notification: <nil>