使用client-go进行k8s相关操作-clientset（一)

1.使用client-go out-of-cluster

2.如果在集群内部可以使用incluster配置，只需要导入"k8s.io/client-go/1.5/rest" 使用config, err := rest.InClusterConfig()

2.需要将kubeconfig文件放到指定位置

package main

import (
"flag"
"k8s.io/client-go/1.5/kubernetes"
"k8s.io/client-go/1.5/pkg/api"
"k8s.io/client-go/1.5/pkg/api/unversioned"
"k8s.io/client-go/1.5/pkg/api/v1"
"k8s.io/client-go/1.5/tools/clientcmd"
"log"
)

var (
kubecOnfig= flag.String("kubeconfig", "./config", "absolute path to the kubeconfig file")
)

func main() {
flag.Parse()
// uses the current context in kubeconfig
config, err := clientcmd.BuildConfigFromFlags("", *kubeconfig)
if err != nil {
panic(err.Error())
}
// 创建client set
clientset, err := kubernetes.NewForConfig(config)
if err != nil {
panic(err.Error())
}
// 获取现有的pod数量
pods, err := clientset.Core().Pods("").List(api.ListOptions{})
check_err(err)
log.Printf("there are %d pods in cluster\n", len(pods.Items))

// 创建pod
pod := new(v1.Pod)
pod.TypeMeta = unversioned.TypeMeta{Kind: "Pod", APIVersion: "v1"}
pod.ObjectMeta = v1.ObjectMeta{Name: "testapi", Namespace: "default", Labels: map[string]string{"name": "testapi"}}
pod.Spec = v1.PodSpec{
RestartPolicy: v1.RestartPolicyAlways,
Containers: []v1.Container{
v1.Container{
Name:  "testapi",
Image: "nginx",
Ports: []v1.ContainerPort{
v1.ContainerPort{
ContainerPort: 80,
Protocol:      v1.ProtocolTCP,
},
},
},
},
}
podname, err := clientset.Core().Pods("default").Create(pod)
check_err(err)
log.Printf("pod %s have cretae\n", podname.ObjectMeta.Name)

// 创建namespace
ns := new(v1.Namespace)
ns.TypeMeta = unversioned.TypeMeta{Kind: "NameSpace", APIVersion: "v1"}
ns.ObjectMeta = v1.ObjectMeta{
Name: "k8s-test",
}
ns.Spec = v1.NamespaceSpec{}
nsname, err := clientset.Core().Namespaces().Create(ns)
check_err(err)
log.Printf("namespace %s have cretae\n", nsname.ObjectMeta.Name)

// 获取现有的pod数量
pods, err = clientset.Core().Pods("").List(api.ListOptions{})
check_err(err)
log.Printf("there are %d pods in cluster\n", len(pods.Items))

//根据名称获取pod
geterpod, err := clientset.Core().Pods("default").Get(podname.ObjectMeta.Name)
check_err(err)
// 删除pod
// 因为关系到时间复杂度 需要加上UID保证唯一性
err = clientset.Core().Pods("default").Delete(geterpod.ObjectMeta.Name, &api.DeleteOptions{Preconditions: &api.Preconditions{UID: &geterpod.ObjectMeta.UID}})
check_err(err)
log.Printf("namespace %s have delete\n", "testapi")

//根据名称获取namespace
geternsname, err := clientset.Core().Namespaces().Get(nsname.ObjectMeta.Name)
check_err(err)

// 删除namespace
err = clientset.Core().Namespaces().Delete(geternsname.ObjectMeta.Name, &api.DeleteOptions{Preconditions: &api.Preconditions{UID: &geternsname.ObjectMeta.UID}})
check_err(err)
log.Printf("namespace %s have delete\n", geternsname.ObjectMeta.Name)

}

func check_err(err error) {
if err != nil {
log.Fatal("got err from apiserver: %s\n", err)
}
}