外部環境への依存をテストする

1. Golang.tokyo 2018/08/21 (Tue) ( @duck8823 )

2. • • @duck8823 • • / • • Kotlin • Golang

3. • • @duck8823 • • • • Kotlin • Golang

4. • • @duck8823 • • • • Kotlin • Golang

5. CI • duck8823/duci • Golang • Docker

8. Webhooks (HTTP) Commit Status (HTTP)

11. ( ) • Incoming HTTP Requests • Git Docker ( ) • • • Outgoing HTTP Requests

12. • Incoming HTTP Requests • Git Docker ( ) ) • ( • • Outgoing HTTP Requests

13. Incoming HTTP Requests func HandlerFunc(w http.ResponseWriter, r *http.Request) { w.WriteHeader(http.StatusOK) body, _ := ioutil.ReadAll(r.Body) w.Write([]byte(fmt.Sprintf("Hello %s.", body))) } • HandlerFunc , . "

14. HandlerFunc func Test_HandlerFunc(t *testing.T) { // given req := httptest.NewRequest("HELLO", "/", strings.NewReader("world")) rec := httptest.NewRecorder() // when HandlerFunc(rec, req) // then if rec.Code != http.StatusOK { t.Errorf("wont %+v, but got %+v", http.StatusOK, rec.Code) } if !reflect.DeepEqual(rec.Body.Bytes(), []byte("Hello world.")) { t.Errorf("wont %+v, but got %+v","Hello world.", string(rec.Body.Bytes())) } }

15. HandlerFunc func Test_HandlerFunc(t *testing.T) { // given req := httptest.NewRequest("HELLO", "/", strings.NewReader("world")) rec := httptest.NewRecorder() // when HandlerFunc(rec, req) // then if rec.Code != http.StatusOK { t.Errorf("wont %+v, but got %+v", http.StatusOK, rec.Code) } if !reflect.DeepEqual(rec.Body.Bytes(), []byte("Hello world.")) { t.Errorf("wont %+v, but got %+v","Hello world.", string(rec.Body.Bytes())) } } http.ResponseWriter (*httptest.ResponseRecorder) *http.Request

16. HandlerFunc func Test_HandlerFunc(t *testing.T) { // given req := httptest.NewRequest("HELLO", "/", strings.NewReader("world")) rec := httptest.NewRecorder() // when HandlerFunc(rec, req) // then if rec.Code != http.StatusOK { t.Errorf("wont %+v, but got %+v", http.StatusOK, rec.Code) } if !reflect.DeepEqual(rec.Body.Bytes(), []byte("Hello world.")) { t.Errorf("wont %+v, but got %+v","Hello world.", string(rec.Body.Bytes())) } }

17. HandlerFunc func Test_HandlerFunc(t *testing.T) { // given req := httptest.NewRequest("HELLO", "/", strings.NewReader("world")) rec := httptest.NewRecorder() // when HandlerFunc(rec, req) // then if rec.Code != http.StatusOK { t.Errorf("wont %+v, but got %+v", http.StatusOK, rec.Code) } if !reflect.DeepEqual(rec.Body.Bytes(), []byte("Hello world.")) { t.Errorf("wont %+v, but got %+v","Hello world.", string(rec.Body.Bytes())) } } *httptest.ResponseRecorder

18. chi HandlerFunc • URL ("/{param}") HandlerFunc go-chi/chi // "/{param}" func ChiHandlerFunc(w http.ResponseWriter, r *http.Request) { w.WriteHeader(http.StatusOK) param := chi.URLParam(r.Context(), "param") w.Write([]byte(fmt.Sprintf("Hello %s.", param))) }

19. chi HandlerFunc func TestChiHandlerFunc(t *testing.T) { // given ctx := chi.NewContext() ctx.Params.Add("param", "world") req := httptest.NewRequest("HELLO", "/", nil).WithContext(ctx) rec := httptest.NewRecorder() // when ChiHandlerFunc(rec, req) // then // ...check rec }

20. chi HandlerFunc func TestChiHandlerFunc(t *testing.T) { // given ctx := chi.NewContext() ctx.Params.Add("param", "world") req := httptest.NewRequest("HELLO", "/", nil).WithContext(ctx) rec := httptest.NewRecorder() // when ChiHandlerFunc(rec, req) // then // ...check rec } context.Context

21. chi HandlerFunc func TestChiHandlerFunc(t *testing.T) { // given ctx := chi.NewContext() ctx.Params.Add("param", "world") req := httptest.NewRequest("HELLO", "/", nil).WithContext(ctx) rec := httptest.NewRecorder() // when ChiHandlerFunc(rec, req) // then // ...check rec } *http.Request context.Context

22. chi HandlerFunc func TestChiHandlerFunc(t *testing.T) { // given ctx := chi.NewContext() ctx.Params.Add("param", "world") req := httptest.NewRequest("HELLO", "/", nil).WithContext(ctx) rec := httptest.NewRecorder() // when ChiHandlerFunc(rec, req) // then // ...check rec }

23. Incoming HTTP Requests • httptest • URL

25. Git Docker (3rd ) • src-d/go-git moby/moby • •

26. type docker struct { moby *client.Client } func (d *docker) Run(image string, cmd ...string) { ctx := context.Background() _, err := d.moby.ImagePull(ctx, image, types.ImagePullOptions{}) con, _ := d.moby.ContainerCreate(ctx, &container.Config{ Image: image, Cmd: cmd }, nil, nil, "") err := d.moby.ContainerStart(ctx, con.ID, types.ContainerStartOptions{}) } • ( docker run )

31. type docker struct { moby *client.Client } func (d *docker) Run(image string, cmd ...string) { ctx := context.Background() _, err := d.moby.ImagePull(ctx, image, types.ImagePullOptions{}) con, _ := d.moby.ContainerCreate(ctx, &container.Config{ Image: image, Cmd: cmd }, nil, nil, "") err := d.moby.ContainerStart(ctx, con.ID, types.ContainerStartOptions{}) } . •

32. Mock • *client.Client type Moby interface { ImagePull(...) (...) ContainerCreate(...) (container.ContainerCreateCreatedBody, error) ContainerStart(...) error } type docker struct { moby Moby }

33. Mock • google/mock/gomock func TestDocker_Run(t *testing.T) { ctrl := gomock.NewController(t) mockMoby := NewMockMoby(ctrl) mockMoby.EXPECT(). ImagePull(gomock.Any(), gomock.Any(), gomock.Any()). AnyTimes(). Return(nil, errors.New("error image pull")) docker := &docker{moby: mockMoby} docker.Run("centos", "echo", "hello world") }

34. Git Docker (3rd ) • • gomock • ( mock )

36. package logger var Writer io.Writer = os.Stdout func Debug(message string) { fmt.Fprintf(Writer, "[DEBUG] %sn", message) } • • ( os.Stdout ) io.Writer (*os.File )

37. func TestDebug(t *testing.T) { // given reader, writer, _ := os.Pipe() logger.Writer = writer // and expected := "[DEBUG] Hello World.n" // when logger.Debug("Hello World.") // then writer.Close() actual, _ := ioutil.ReadAll(reader) if string(actual) != expected { t.Errorf("wont %s, but got %s", expected, actual) } }

38. func TestDebug(t *testing.T) { // given reader, writer, _ := os.Pipe() logger.Writer = writer // and expected := "[DEBUG] Hello World.n" // when logger.Debug("Hello World.") // then writer.Close() actual, _ := ioutil.ReadAll(reader) if string(actual) != expected { t.Errorf("wont %s, but got %s", expected, actual) } } ) ( ).( 1 ( ( 2

42. • io.Writer io.Pipe

44. • func Debug(message string) { now := time.Now().Format("2006-01-02 15:04:05") fmt.Fprintf(Writer, "%s [DEBUG] %sn", now, message) }

45. time.Now() • func Debug(message string) { now := clock.Now().Format("2006-01-02 15:04:05") fmt.Fprintf(Writer, "%s [DEBUG] %sn", now, message) } package clock import "time" var Now = func () time.Time { return time.Now() }

46. func TestDebug(t *testing.T) { // given jst, _ := time.LoadLocation("Asia/Tokyo") clock.Now = func() time.Time { return time.Date(1987, time.March, 27, 09, 34, 00, 00, jst) } // and reader, writer, _ := os.Pipe() logger.Writer = writer // and expected := "1987-03-27 09:34:00 [DEBUG] Hello World.n" // when logger.Debug("Hello World.") // then // ... }

47. func TestDebug(t *testing.T) { // given jst, _ := time.LoadLocation("Asia/Tokyo") clock.Now = func() time.Time { return time.Date(1987, time.March, 27, 09, 34, 00, 00, jst) } // and reader, writer, _ := os.Pipe() logger.Writer = writer // and expected := "1987-03-27 09:34:00 [DEBUG] Hello World.n" // when logger.Debug("Hello World.") // then // ... } .

48. func TestDebug(t *testing.T) { // given jst, _ := time.LoadLocation("Asia/Tokyo") clock.Now = func() time.Time { return time.Date(1987, time.March, 27, 09, 34, 00, 00, jst) } // and reader, writer, _ := os.Pipe() logger.Writer = writer // and expected := "1987-03-27 09:34:00 [DEBUG] Hello World.n" // when logger.Debug("Hello World.") // then // ... }

49. • ( ) • time.Now

51. Outgoing HTTP Requests • EO • IL P • H / D G RA

52. Outgoing HTTP Requests • 2 ) ) / ( ( func TestRequest(t *testing.T) { defer gock.Off() gock.New("http://example.com"). Post("/"). Reply(http.StatusOK) resp, _ := http.Post("http://example.com/", "application/json", nil) if resp.StatusCode != http.StatusOK { t.Errorf("wont %+v, but got %+v", http.StatusOK, resp.StatusCode) } }

55. Outgoing HTTP Requests • •

60. Webhooks (HTTP) Commit Status (HTTP) )& ) . & &(

62. • oc • H • ) ( k • P T • p • he ) (M

外部環境への依存をテストする

Shunsuke Maeda

外部環境への依存をテストする