golang best practice 之 dev测试

基本过程

1. coding in local IDE，write unit test,
2. add & run integrate test(tradeoff between自动化与手动，如果自动化写的少，多动手)
3. deploy to dev environment
4. deploy to qa or production environment. not be discussed on this page

Requirement

Environment in logic

1. IDE environment for develop effectively. Should support debug interactively with ide breakpoint.
2. Integrate Test environment. For run integrate by hand or automatically.
3. Local Environment.
4. Dev environment.
   And QA environment、Prod environment not maintained by dev

Environment in implement

Realness

Unit Test -> Integrate Test -> Dev, from fake to real

Implement

Run unit test by hand or script with go test.

Unit Test

Write Unit Test Withfx support to inject some mock component, example:

func TestFxPopluate(t *testing.T) {
 // Some external module that provides a user name.
 type Username string
 UserModule := fx.Provide(func() Username { return "john" })

 var user Username
 app := fxtest.New(
  t,
  UserModule,
  fx.Populate(&user),
 )
 app.RequireStart().RequireStop()
 t.Log(user)
}

Integrate Test

use httptest library, example

func TestHttpTestApi(t *testing.T) {
 InitTest()
 var r *gin.Engine
 app := fxtest.New(t, logger.Module, database.Module, cache.Module, config.Module,
  dao.Module, handler.ModuleWithDep, router.Module, fx.Populate(&r))
 app.RequireStart().RequireStop()
 // create request
 req, err := http.NewRequest("GET", "/api/v3/test/ping", nil)
 if err != nil {
  t.Fatal(err)
 }

 // response checker
 rr := httptest.NewRecorder()

 r.ServeHTTP(rr, req)

 if status := rr.Code; status != http.StatusForbidden {
  t.Errorf("handler returned wrong status code: got %v want %v",
   status, http.StatusOK)
 }

 return
 /*
  expected := `{"message": "pong"}`
  if rr.Body.String() != expected {
   t.Errorf("handler returned unexpected body: got %v want %v",
    rr.Body.String(), expected)
  }
 */
}

Distinguish env by shell env value or cmd flag or both, supported by config library

IDE env、Integrate Test env、Local env can use same config、same environment, but with some difference, so use different flag. Different Requirement

• IDE env require run in IDE, so more mock component. Actually one of server、fe run separately in IDE，other run in docker
• Integrate Test should clean db and other state before every run. Integrate can be run in any one of IDE、local、dev、QA env with clean db、state
• Local env require keep state.

Use docker to implement this.

Env define: ["ide", "local", "dev"], and ["qa", "prod"]

Use shell env、cmd flags to determine which env to run, as to load different config and component.

monkey patch

https://github.com/bouk/monkey

可以极大地简化使用依赖注入时的mock替换，避免在更深的层次进行替换时的繁琐操作。