user_snippet.go

// this is under the user.go file
func (h *Handler) loginUser(c echo.Context) error {

	username := c.FormValue("username")
	password := c.FormValue("password")

	user := h.service.GetByUsername(username)
	if user == nil || user.Password != password {
		return echo.ErrUnauthorized
	}

	sess, err := session.Get("session", c)
	if err != nil {
		log.Fatal(err)
		return err
	}
	sess.Options = &sessions.Options{
		Path:     "/",
		MaxAge:   0,
		HttpOnly: false,
		Secure:   true,
	}
	sess.Values["name"] = username
	sess.Save(c.Request(), c.Response())
	return c.NoContent(http.StatusOK)
}

// this is under the user_test.go file
func TestAuthenticateUser(t *testing.T) {

	e := echo.New()
	e.Use(session.Middleware(sessions.NewCookieStore([]byte("secret"))))
	h := &Handler{&store} // custom store interface

	t.Run("it returns a valid session for successful login", func(t *testing.T) {
		f := make(url.Values)
		f.Set("username", "john")
		f.Set("password", "secret@123")

		req := httptest.NewRequest(http.MethodPost, "/", strings.NewReader(f.Encode()))
		req.Header.Set(echo.HeaderContentType, echo.MIMEApplicationForm)
		res := httptest.NewRecorder()

		c := e.NewContext(req, res)
		AssertNil(t, h.loginUser(c))
		AssertEqual(t, http.StatusOK, res.Code)

		sess, err := session.Get("session", c)
		AssertNil(t, err)
		AssertEqual(t, "john", sess.Values["name"])
	})
}