clientgo中使用informer开发自定义operator

开发operator一共分为5步骤

1、创建config

config的创建有两种方式

1、clientcmd.BuildConfigFromFlags

config, err := clientcmd.BuildConfigFromFlags("", clientcmd.RecommendedHomeFile)
	if err != nil {
		//访问集群内
		inClusterConfig, err := rest.InClusterConfig()
		if err != nil {
			log.Fatalln("can't get config")
		}
		config = inClusterConfig
	}

clientcmd.RecommendedHomeFile可以自己指定路径一般为~/.kube/config

2、config,err :=config.GetConfig()

2、创建client

lientset, err := kubernetes.NewForConfig(config)
	if err != nil {
		log.Fatalln("can't create client")
	}

3、创建informer

factory := informers.NewSharedInformerFactory(clientset, 0)
serviceInformer := factory.Core().V1().Services()
ingressInformer := factory.Networking().V1().Ingresses()

4、add event handler

//注册到eventhandler
	controller := pkg.NewController(clientset, serviceInformer, ingressInformer)
	stopCh := make(chan struct{})
	factory.Start(stopCh)
	//等待所有的informer缓存同步
	factory.WaitForCacheSync(stopCh)

在注册到eventhandler中，会进行事件的操作，如：

func NewController(client kubernetes.Interface, serviceInformer informer.ServiceInformer, ingressInformer netInformer.IngressInformer) controller {
	c := controller{
		client:        client,
		ingressLister: ingressInformer.Lister(),
		serviceLister: serviceInformer.Lister(),
		queue:         workqueue.NewNamedRateLimitingQueue(workqueue.DefaultControllerRateLimiter(), "ingressManager"),
	}

	serviceInformer.Informer().AddEventHandler(cache.ResourceEventHandlerFuncs{
		AddFunc:    c.addService,
		UpdateFunc: c.updateService,
	})
	//cache.Store()

	ingressInformer.Informer().AddEventHandler(cache.ResourceEventHandlerFuncs{
		DeleteFunc: c.deleteIngress,
	})

	return c
}

5、启动informer

controller.Run(stopCh)

6、informer案例

案例1：

案例2：