fix: move some logic to domain entities

domain/usecase/book/interface.go

@@ -29,7 +29,7 @@ type UseCase interface {
 	GetBook(id entity.ID) (*entity.Book, error)
 	SearchBooks(query string) ([]*entity.Book, error)
 	ListBooks() ([]*entity.Book, error)
-	CreateBook(e *entity.Book) (entity.ID, error)
+	CreateBook(title string, author string, pages int, quantity int) (entity.ID, error)
 	UpdateBook(e *entity.Book) error
 	DeleteBook(id entity.ID) error
 }

domain/usecase/book/mock/book.go

@@ -5,9 +5,10 @@
 package mock
 
 import (
+	reflect "reflect"
+
 	entity "github.com/eminetto/clean-architecture-go-v2/domain/entity"
 	gomock "github.com/golang/mock/gomock"
-	reflect "reflect"
 )
 
 // MockReader is a mock of Reader interface
@@ -324,18 +325,18 @@ func (mr *MockUseCaseMockRecorder) ListBooks() *gomock.Call {
 }
 
 // CreateBook mocks base method
-func (m *MockUseCase) CreateBook(e *entity.Book) (entity.ID, error) {
+func (m *MockUseCase) CreateBook(title, author string, pages, quantity int) (entity.ID, error) {
 	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "CreateBook", e)
+	ret := m.ctrl.Call(m, "CreateBook", title, author, pages, quantity)
 	ret0, _ := ret[0].(entity.ID)
 	ret1, _ := ret[1].(error)
 	return ret0, ret1
 }
 
 // CreateBook indicates an expected call of CreateBook
-func (mr *MockUseCaseMockRecorder) CreateBook(e interface{}) *gomock.Call {
+func (mr *MockUseCaseMockRecorder) CreateBook(title, author, pages, quantity interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "CreateBook", reflect.TypeOf((*MockUseCase)(nil).CreateBook), e)
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "CreateBook", reflect.TypeOf((*MockUseCase)(nil).CreateBook), title, author, pages, quantity)
 }
 
 // UpdateBook mocks base method

domain/usecase/book/service.go

@@ -22,10 +22,16 @@ func NewService(r Repository) *Service {
 }
 
 //CreateBook create a book
-func (s *Service) CreateBook(e *entity.Book) (entity.ID, error) {
-	e.ID = entity.NewID()
-	e.CreatedAt = time.Now()
-	return s.repo.Create(e)
+func (s *Service) CreateBook(title string, author string, pages int, quantity int) (entity.ID, error) {
+	b, err := entity.NewBook(title, author, pages, quantity)
+	if err != nil {
+		return b.ID, err
+	}
+	err = b.Validate()
+	if err != nil {
+		return b.ID, err
+	}
+	return s.repo.Create(b)
 }
 
 //GetBook get a book
@@ -76,5 +82,10 @@ func (s *Service) DeleteBook(id entity.ID) error {
 
 //UpdateBook Update a book
 func (s *Service) UpdateBook(e *entity.Book) error {
+	err := e.Validate()
+	if err != nil {
+		return err
+	}
+	e.UpdatedAt = time.Now()
 	return s.repo.Update(e)
 }

domain/usecase/book/service_test.go

@@ -2,6 +2,7 @@ package book
 
 import (
 	"testing"
+	"time"
 
 	"github.com/eminetto/clean-architecture-go-v2/domain/entity"
 
@@ -12,25 +13,34 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+func newFixtureBook() *entity.Book {
+	return &entity.Book{
+		Title:     "I Am Ozzy",
+		Author:    "Ozzy Osbourne",
+		Pages:     294,
+		Quantity:  1,
+		CreatedAt: time.Now(),
+	}
+}
+
 func Test_Create(t *testing.T) {
 	repo := book.NewInmemRepository()
 	m := NewService(repo)
-	u := entity.NewFixtureBook()
-	id, err := m.CreateBook(u)
+	u := newFixtureBook()
+	_, err := m.CreateBook(u.Title, u.Author, u.Pages, u.Quantity)
 	assert.Nil(t, err)
-	assert.Equal(t, u.ID, id)
 	assert.False(t, u.CreatedAt.IsZero())
 }
 
 func Test_SearchAndFind(t *testing.T) {
 	repo := book.NewInmemRepository()
 	m := NewService(repo)
-	u1 := entity.NewFixtureBook()
-	u2 := entity.NewFixtureBook()
+	u1 := newFixtureBook()
+	u2 := newFixtureBook()
 	u2.Title = "Lemmy: Biography"
 
-	uID, _ := m.CreateBook(u1)
-	_, _ = m.CreateBook(u2)
+	uID, _ := m.CreateBook(u1.Title, u1.Author, u1.Pages, u1.Quantity)
+	_, _ = m.CreateBook(u2.Title, u2.Author, u2.Pages, u2.Quantity)
 
 	t.Run("search", func(t *testing.T) {
 		c, err := m.SearchBooks("ozzy")
@@ -58,8 +68,8 @@ func Test_SearchAndFind(t *testing.T) {
 func Test_Update(t *testing.T) {
 	repo := book.NewInmemRepository()
 	m := NewService(repo)
-	u := entity.NewFixtureBook()
-	id, err := m.CreateBook(u)
+	u := newFixtureBook()
+	id, err := m.CreateBook(u.Title, u.Author, u.Pages, u.Quantity)
 	assert.Nil(t, err)
 	saved, _ := m.GetBook(id)
 	saved.Title = "Lemmy: Biography"
@@ -72,9 +82,9 @@ func Test_Update(t *testing.T) {
 func TestDelete(t *testing.T) {
 	repo := book.NewInmemRepository()
 	m := NewService(repo)
-	u1 := entity.NewFixtureBook()
-	u2 := entity.NewFixtureBook()
-	u2ID, _ := m.CreateBook(u2)
+	u1 := newFixtureBook()
+	u2 := newFixtureBook()
+	u2ID, _ := m.CreateBook(u2.Title, u2.Author, u2.Pages, u2.Quantity)
 
 	err := m.DeleteBook(u1.ID)
 	assert.Equal(t, domain.ErrNotFound, err)