Go-Kubernetes-Client-go编程从Pod管理到CRD开发

圣殿骑士-Khtangc2026-08-21 10:36

Go-Kubernetes-Client-go编程从Pod管理到CRD开发

文章导语

Client-go是Kubernetes官方的Go客户端库，用于与K8s API Server交互。本文深入Client-go的核心组件：Informer、WorkQueue、Lister，实现从基础CRUD到自定义Controller。

一、Client-go基础操作

go 复制代码

func NewClientSet() (*kubernetes.Clientset, error) {
    config, err := clientcmd.BuildConfigFromFlags("", kubeconfig)
    if err != nil {
        return nil, err
    }
    return kubernetes.NewForConfig(config)
}

// List Pods
func ListPods(clientset *kubernetes.Clientset, namespace string) {
    pods, err := clientset.CoreV1().Pods(namespace).List(context.TODO(), metav1.ListOptions{})
    for _, pod := range pods.Items {
        fmt.Printf("Pod: %s, Status: %s\n", pod.Name, pod.Status.Phase)
    }
}

二、Informer机制

go 复制代码

func WatchPods(clientset *kubernetes.Clientset) {
    factory := informers.NewSharedInformerFactory(clientset, 30*time.Second)
    podInformer := factory.Core().V1().Pods()
    
    podInformer.Informer().AddEventHandler(cache.ResourceEventHandlerFuncs{
        AddFunc: func(obj interface{}) {
            pod := obj.(*corev1.Pod)
            fmt.Printf("Pod Added: %s\n", pod.Name)
        },
        UpdateFunc: func(oldObj, newObj interface{}) {
            fmt.Println("Pod Updated")
        },
        DeleteFunc: func(obj interface{}) {
            fmt.Println("Pod Deleted")
        },
    })
    
    stopCh := make(chan struct{})
    defer close(stopCh)
    factory.Start(stopCh)
    factory.WaitForCacheSync(stopCh)
    <-stopCh
}

三、全文总结

Client-go是K8s生态的核心Go库
Informer实现本地缓存+事件通知
WorkQueue限流+去重处理事件
CRD+Controller扩展K8s能力

参考文献

Client-go官方文档
K8s Sample Controller
Kubebuilder框架文档