如何使用伪造的客户端为客户端编写简单的测试？

Question

Problem

I am looking for the correct way to test my code below, I couldn't find any examples how can I do it. Only main_test.go but it is missing main.go and for me, it isn't obvious how can I use it. I also went through Github issues but I can not find anything helpful.

Function:

import (
  "fmt"
  "k8s.io/api/core/v1"
  metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
  fake "k8s.io/client-go/kubernetes/fake"
  "time"
)

func GetNamespaceCreationTime(namespace string) int64 {
    config, err := rest.InClusterConfig()
    if err != nil {
        panic(err.Error())
    }
    clientset, err := kubernetes.NewForConfig(config)
    if err != nil {
        panic(err.Error())
    }

    ns, err := clientset.CoreV1().Namespaces().Get(namespace, metav1.GetOptions{})
    if err != nil {
        panic(err.Error())
    }
    fmt.Printf("%v 
", ns.CreationTimestamp)
    return (ns.GetCreationTimestamp().Unix())
}

Test:

I think my test should look like below, but how can I use config := fake.NewSimpleClientset(), should I pass it into GetNamespaceCreationTime function?

func TestGetNamespaceCreationTime(t *testing.T) {
  config := fake.NewSimpleClientset()
  got := GetNamespaceCreationTime("default")
  want := int64(1257894000)

  nsMock := config.CoreV1().Namespaces()
  nsMock.Create(&v1.Namespace{
    ObjectMeta: metav1.ObjectMeta{
      Name:              "default",
      CreationTimestamp: metav1.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC),
    },
  })

  if got != want {
    t.Errorf("got %q want %q", got, want)
  }