go service snippet

goserver.go

router := httprouter.New()
router.POST("/api/login", httpHandler(login))

func httpHandler(fn httpRouterFunc) httpRouterFunc {
	return func(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
		fn(w, r, ps)
	}
}

func login(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
	// prepare input
	credentials, err := credentialsFromRequest(r)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	authenticator := auth.NewAuthenticator(authRepo)

	reader := users.NewReader(usersRepo)
	res, authErr := authenticator.Login(*credentials, reader)
	if authErr != nil {
		respondWithError(authErr, w)
		return
	}

	respond(w, res)
}

func (auth authenticator) Login(cred models.Credentials, reader users.Reader) (*Response, *models.Error) {
	users, err := reader.ReadByUsername(cred.Username)
	if err != nil {
		return nil, err
	}

	var match *models.User

	for _, user := range users {
		if crypto.CompareHashAndPassword(user.Password, cred.Password) {
			match = &user
			break
		}
	}

	if match == nil {
		return nil, &models.Error{StatusCode: 404, Message: "User Not Found"}
	}

	token, err := auth.repo.Insert(*match)
	if err != nil {
		return nil, &models.Error{StatusCode: 500, Message: err.Error()}
	}

	res := Response{User: match.Response(), AccessToken: *token}
	return &res, nil
}