Kubernetes客户端-go使用线人监视部署。

Question

我在试着利用客户端的告密者来获得部署的副本。每当自动标度更改副本的数量时，我都需要检索它以处理其他逻辑。我以前使用了Watch()函数，但是有一些与超时和连接删除不一致的地方。

下面的代码显示了实现的示例：

labelOptions := informers.WithTweakListOptions(func(opts *v1.ListOptions) {
    opts.FieldSelector = "metadata.name=" + name
})
factory := informers.NewSharedInformerFactoryWithOptions(clientSet, 2*time.Second, informers.WithNamespace(namespace), labelOptions)
informer := factory.Apps().V1().Deployments().Informer()

// Using the channels and goroutines below didn't show changes:
stopper := make(chan struct{})
defer close(stopper)
//go func() {
informer.AddEventHandler(cache.ResourceEventHandlerFuncs{
    AddFunc: func(obj interface{}) {
        mObj, ok := obj.(*appsv1.Deployment)
        if !ok {
            panic(spew.Sdump("informer returned invalid type", mObj))
        }

        replicas := int(*mObj.Spec.Replicas)
        logger.Infof("updating replicas to %d", replicas)

        sendUpdates() // use updates elsewhere
    },

    
    UpdateFunc: func(oldObj, newObj interface{}) {
        old, ok := oldObj.(*appsv1.Deployment)
        if !ok {
            panic(spew.Sdump("informer returned invalid type", old))
        }
        newDeployment, ok := newObj.(*appsv1.Deployment)
        if !ok {
            panic(spew.Sdump("informer returned invalid type", newDeployment))
        }
        oldReplicas := int(*old.Spec.Replicas)
        newReplicas := int(*newDeployment.Spec.Replicas)
        if oldReplicas != newReplicas {
            sendUpdates()
        }
    },
})

//factory.Start(wait.NeverStop)
//factory.WaitForCacheSync(wait.NeverStop)
informer.Run(stopper)

当Kubernetes自动标尺或我手动更改部署副本时，我会得到deployment.apps/app scaled，但它不会被Informer捕获。日志中没有打印任何内容，它进入崩溃循环，没有错误消息。

我使用了以下资源：

• https://dev.to/davidsbond/go-creating-dynamic-kubernetes-informers-1npi
• What's the best way to get notified when kubernetes Deployments change using the k8s.io/client-go library?
• kubernetes filter objects in Informer

Answer 1

有几件事要注意：

在调用anything.

• Using之前，请确保Informer被直接调用(informer := factory.Apps().V1().Deployments().Informer())或Start()不会启动a goroutine来启动SharedInformerFactory，因为informerFactory.Start()在内部使用该方法。
• 还将停止informerFactory.WaitForCacheSync()方法的工作，从而导致它为开始的告密者获取错误的数据。H 211F 212

labelOptions := informers.WithTweakListOptions(func(opts *v1.ListOptions) {
    opts.FieldSelector = "metadata.name=" + name
})
factory := informers.NewSharedInformerFactoryWithOptions(clientSet, 2*time.Second, informers.WithNamespace(namespace), labelOptions)
informer := factory.Apps().V1().Deployments().Informer()

informer.AddEventHandler(cache.ResourceEventHandlerFuncs{
    AddFunc: func(obj interface{}) {
        mObj, ok := obj.(*appsv1.Deployment)
        if !ok {
            doSomething()
        }
        replicas := int(*mObj.Spec.Replicas)
        doSomething() 
    },

    
    UpdateFunc: func(oldObj, newObj interface{}) {
        old, ok := oldObj.(*appsv1.Deployment)
        if !ok {
            doSomething()
        }
        newDeployment, ok := newObj.(*appsv1.Deployment)
        if !ok {
            doSomething()
        }
        oldReplicas := int(*old.Spec.Replicas)
        newReplicas := int(*newDeployment.Spec.Replicas)
        if oldReplicas != newReplicas {
            doSomething()
        }
    },
})

// Initializes all active informers and starts the internal goroutine
factory.Start(wait.NeverStop)
factory.WaitForCacheSync(wait.NeverStop)