k8s怎么监听自定义资源的变更?(2)

接上一篇当生成下面代码之后怎么去使用呢？

1.生成crd文件

这里我们通过kubebuilder的一个子项目 controller-gen 来生成crd文件
https://github.com/kubernetes-sigs/controller-tools

curl -L -o https://github.com/kubernetes-sigs/controller-tools;
go install controller-tools/cmd/controller-gen;

controller-gen crd paths=./pkg/apis/... output:crd:dir=config/crd

可以看到已经生成成功了。

apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
  annotations:
    controller-gen.kubebuilder.io/version: (devel)
  name: foos.core.bigbird0101
spec:
  group: core.bigbird0101
  names:
    kind: Foo
    listKind: FooList
    plural: foos
    singular: foo
  scope: Namespaced
  versions:
  - name: v1
    schema:
      openAPIV3Schema:
        description: Foo is a specification for a Foo resource
        properties:
          apiVersion:
            description: |-
              APIVersion defines the versioned schema of this representation of an object.
              Servers should convert recognized schemas to the latest internal value, and
              may reject unrecognized values.
              More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources
            type: string
          kind:
            description: |-
              Kind is a string value representing the REST resource this object represents.
              Servers may infer this from the endpoint the client submits requests to.
              Cannot be updated.
              In CamelCase.
              More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds
            type: string
          metadata:
            type: object
          spec:
            description: FooSpec is the spec for a Foo resource
            properties:
              deploymentName:
                type: string
              replicas:
                format: int32
                type: integer
            required:
            - deploymentName
            - replicas
            type: object
          status:
            description: FooStatus is the status for a Foo resource
            properties:
              availableReplicas:
                format: int32
                type: integer
            required:
            - availableReplicas
            type: object
        required:
        - spec
        - status
        type: object
    served: true
    storage: true

在 k8s当中执行一下这个yaml，可以看到已经成功

apiVersion: core.bigbird0101/v1
kind: Foo
metadata:
  name: test-foo
spec:
    deploymentName: "test-foo"
    replicas: 1
status:     
    availableReplicas: 1

再去执行 可以看到已经成功

2.写监听代码

package main

import (
	v1 "bigbird0101/crd-test/pkg/apis/core/v1"
	"bigbird0101/crd-test/pkg/generated/clientset/versioned"
	"bigbird0101/crd-test/pkg/generated/informers/externalversions"
	"context"
	"fmt"
	"k8s.io/client-go/tools/cache"
	"k8s.io/client-go/tools/clientcmd"
)

func main() {
	flags, _ := clientcmd.BuildConfigFromFlags("", clientcmd.RecommendedHomeFile)
	client, _ := versioned.NewForConfig(flags)
	factory := externalversions.NewSharedInformerFactoryWithOptions(client, 0,externalversions.WithNamespace("default"))
	informer := factory.Core().V1().Foos().Informer()
	_, err := informer.AddEventHandler(cache.ResourceEventHandlerFuncs{
		AddFunc: func(obj interface{}) {
			foo := obj.(*v1.Foo)
			fmt.Printf("foo added: %v\n", foo)
		},
		UpdateFunc: func(oldObj, newObj interface{}) {
			foo := oldObj.(*v1.Foo)
			fmt.Printf("foo UpdateFunc: %v\n", foo)
			foo2 := newObj.(*v1.Foo)
			fmt.Printf("foo UpdateFunc: %v\n", foo2)
		},
		DeleteFunc: func(obj interface{}) {
			foo := obj.(*v1.Foo)
			fmt.Printf("foo Deleted: %v\n", foo)
		},
	})
	if err != nil {
		fmt.Println(err)
		return
	}
	informer.Run(context.Background().Done())
}

可以代码测试
删除资源和创建资源 可以看到都收到了通知