Get_sale_order handler and use case

cmd/main.go

@@ -6,7 +6,9 @@ import (
 	"github.com/kiaplayer/clean-architecture-example/internal/adapters/repositories/sale_order"
 	saleorderservice "github.com/kiaplayer/clean-architecture-example/internal/domain/service/sale_order"
 	createsaleorderusecase "github.com/kiaplayer/clean-architecture-example/internal/domain/use_case/create_sale_order"
+	getsaleorderusecase "github.com/kiaplayer/clean-architecture-example/internal/domain/use_case/get_sale_order"
 	"github.com/kiaplayer/clean-architecture-example/internal/handlers/create_sale_order"
+	"github.com/kiaplayer/clean-architecture-example/internal/handlers/get_sale_order"
 	"github.com/kiaplayer/clean-architecture-example/pkg/generators"
 	"github.com/kiaplayer/clean-architecture-example/pkg/storage/db"
 )
@@ -19,7 +21,10 @@ func main() {
 	numberGenerator := generators.NewNumberGenerator()
 	saleOrderRepo := sale_order.NewRepository(conn)
 	saleOrderService := saleorderservice.NewService(saleOrderRepo)
-	useCase := createsaleorderusecase.NewUseCase(timeGenerator, numberGenerator, saleOrderService)
 
-	create_sale_order.NewHandler(useCase, transactor)
+	create_sale_order.NewHandler(
+		createsaleorderusecase.NewUseCase(timeGenerator, numberGenerator, saleOrderService),
+		transactor,
+	)
+	get_sale_order.NewHandler(getsaleorderusecase.NewUseCase(saleOrderService))
 }

internal/domain/service/sale_order/service.go

@@ -11,6 +11,7 @@ import (
 
 type repository interface {
 	CreateOrder(ctx context.Context, order *document.SaleOrder) (*document.SaleOrder, error)
+	GetByID(ctx context.Context, id uint64) (*document.SaleOrder, error)
 }
 
 type Service struct {
@@ -28,13 +29,24 @@ func (s *Service) CreateOrder(ctx context.Context, order *document.SaleOrder) (*
 	if err != nil {
 		return order, err
 	}
-	return s.repository.CreateOrder(ctx, order)
-	// TODO: Additinal logic (reserve, email...)
+	savedSaleOrder, err := s.repository.CreateOrder(ctx, order)
+	if err != nil {
+		return nil, err
+	}
+	// TODO: Additinal logic goes here
+	// - Reserve products
+	// - Send emails to customer and manager (via pgq)
+	// - etc
+	return savedSaleOrder, nil
 }
 
 func (s *Service) ValidateOrder(order *document.SaleOrder) (*document.SaleOrder, error) {
 	if !slices.Contains(document.ValidStatuses, order.Status) {
-		return order, fmt.Errorf("bad status: %d", order.Status)
+		return nil, fmt.Errorf("bad status: %d", order.Status)
 	}
 	return order, nil
 }
+
+func (s *Service) GetOrderByID(ctx context.Context, id uint64) (*document.SaleOrder, error) {
+	return s.repository.GetByID(ctx, id)
+}

internal/domain/service/sale_order/service_test.go

@@ -62,7 +62,7 @@ func TestCreateOrder_ValidateError(t *testing.T) {
 	actualSaleOrder, actualErr := service.CreateOrder(ctx, saleOrder)
 
 	// assert
-	assert.Equal(t, saleOrder, actualSaleOrder)
+	assert.Nil(t, actualSaleOrder)
 	assert.ErrorContains(t, actualErr, "bad status")
 }
 
@@ -95,3 +95,32 @@ func TestCreateOrder_CreateError(t *testing.T) {
 	assert.Nil(t, actualSaleOrder)
 	assert.ErrorContains(t, actualErr, createErr.Error())
 }
+
+func TestGetOrderByID_Success(t *testing.T) {
+	// arrange
+	ctrl := gomock.NewController(t)
+	ctx := context.Background()
+
+	repositoryMock := mocks.NewMockrepository(ctrl)
+
+	service := NewService(repositoryMock)
+
+	saleOrder := &document.SaleOrder{
+		Document: document.Document{
+			ID:     1,
+			Date:   time.Now().Truncate(time.Second),
+			Number: "0001",
+		},
+	}
+
+	repositoryMock.EXPECT().
+		GetByID(ctx, saleOrder.ID).
+		Return(saleOrder, nil)
+
+	// act
+	actualSaleOrder, actualErr := service.GetOrderByID(ctx, saleOrder.ID)
+
+	// assert
+	assert.NoError(t, actualErr)
+	assert.Equal(t, saleOrder, actualSaleOrder)
+}

internal/domain/use_case/get_sale_order/use_case.go

@@ -0,0 +1,26 @@
+//go:generate mockgen -package=$GOPACKAGE -source=$GOFILE -destination=mocks/$GOFILE
+package get_sale_order
+
+import (
+	"context"
+
+	"github.com/kiaplayer/clean-architecture-example/internal/domain/entity/document"
+)
+
+type saleOrderService interface {
+	GetOrderByID(ctx context.Context, id uint64) (*document.SaleOrder, error)
+}
+
+type UseCase struct {
+	saleOrderService saleOrderService
+}
+
+func NewUseCase(sos saleOrderService) *UseCase {
+	return &UseCase{
+		saleOrderService: sos,
+	}
+}
+
+func (u *UseCase) Handle(ctx context.Context, id uint64) (saleOrder *document.SaleOrder, err error) {
+	return u.saleOrderService.GetOrderByID(ctx, id)
+}

internal/domain/use_case/get_sale_order/use_case_test.go

@@ -0,0 +1,69 @@
+package get_sale_order
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/assert"
+
+	"github.com/kiaplayer/clean-architecture-example/internal/domain/entity/document"
+	mocks "github.com/kiaplayer/clean-architecture-example/internal/domain/use_case/get_sale_order/mocks"
+)
+
+func TestHandle_Success(t *testing.T) {
+	// arrange
+	ctrl := gomock.NewController(t)
+	ctx := context.Background()
+
+	saleOrderServiceMock := mocks.NewMocksaleOrderService(ctrl)
+
+	useCase := NewUseCase(saleOrderServiceMock)
+
+	saleOrder := &document.SaleOrder{
+		Document: document.Document{
+			ID: 1,
+		},
+	}
+
+	saleOrderServiceMock.EXPECT().
+		GetOrderByID(ctx, saleOrder.ID).
+		Return(saleOrder, nil)
+
+	// act
+	actualSaleOrder, actualErr := useCase.Handle(ctx, saleOrder.ID)
+
+	// assert
+	assert.NoError(t, actualErr)
+	assert.Equal(t, saleOrder, actualSaleOrder)
+}
+
+func TestHandle_Error(t *testing.T) {
+	// arrange
+	ctrl := gomock.NewController(t)
+	ctx := context.Background()
+
+	saleOrderServiceMock := mocks.NewMocksaleOrderService(ctrl)
+
+	useCase := NewUseCase(saleOrderServiceMock)
+
+	saleOrder := &document.SaleOrder{
+		Document: document.Document{
+			ID: 1,
+		},
+	}
+
+	getErr := errors.New("get error")
+
+	saleOrderServiceMock.EXPECT().
+		GetOrderByID(ctx, saleOrder.ID).
+		Return(nil, getErr)
+
+	// act
+	actualSaleOrder, actualErr := useCase.Handle(ctx, saleOrder.ID)
+
+	// assert
+	assert.Nil(t, actualSaleOrder)
+	assert.ErrorContains(t, actualErr, getErr.Error())
+}

internal/handlers/create_sale_order/handler.go

@@ -55,7 +55,7 @@ func (h *Handler) Handle(ctx context.Context, writer http.ResponseWriter, reques
 	saleOrderForCast, err := h.transactor.RunInTx(ctx, func(ctx context.Context) (any, error) {
 		return h.useCase.Handle(ctx, products, company, customer, appendUser)
 	})
-	if err != nil || saleOrderForCast == nil {
+	if err != nil {
 		writer.WriteHeader(http.StatusInternalServerError)
 		return
 	}

internal/handlers/get_sale_order/handler.go

@@ -0,0 +1,74 @@
+//go:generate mockgen -package=$GOPACKAGE -source=$GOFILE -destination=mocks/$GOFILE
+package get_sale_order
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net/http"
+	"strconv"
+
+	"github.com/kiaplayer/clean-architecture-example/internal/domain/entity/document"
+)
+
+type useCase interface {
+	Handle(
+		ctx context.Context,
+		id uint64,
+	) (saleOrder *document.SaleOrder, err error)
+}
+
+type Handler struct {
+	useCase useCase
+}
+
+func NewHandler(u useCase) *Handler {
+	return &Handler{
+		useCase: u,
+	}
+}
+
+func (h *Handler) Handle(ctx context.Context, writer http.ResponseWriter, request *http.Request) {
+	err := h.checkAccess(request)
+	if err != nil {
+		writer.WriteHeader(http.StatusForbidden)
+		_, _ = writer.Write([]byte(err.Error()))
+		return
+	}
+
+	saleOrderID, err := h.validateAndPrepare(request)
+	if err != nil {
+		writer.WriteHeader(http.StatusBadRequest)
+		_, _ = writer.Write([]byte(err.Error()))
+		return
+	}
+
+	saleOrder, err := h.useCase.Handle(ctx, saleOrderID)
+	if err != nil {
+		writer.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	_, _ = writer.Write([]byte(fmt.Sprintf("SaleOrder ID = %d", saleOrder.ID)))
+
+	return
+}
+
+func (h *Handler) checkAccess(request *http.Request) error {
+	if request.Method == http.MethodDelete {
+		return errors.New("access denied") // demo only
+	}
+	return nil
+}
+
+func (h *Handler) validateAndPrepare(request *http.Request) (uint64, error) {
+	id, err := strconv.ParseInt(request.URL.Query().Get("id"), 10, 64)
+	if err != nil {
+		return 0, fmt.Errorf("bad id: %w", err)
+	}
+	if id <= 0 {
+		return 0, errors.New("bad id")
+	}
+
+	return uint64(id), nil
+}