[hw-3] loms service

loms/internal/app/server/server.go

@@ -0,0 +1,148 @@
+package server
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/pkg/errors"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+	"google.golang.org/protobuf/types/known/emptypb"
+
+	"route256/loms/internal/domain/entity"
+	"route256/loms/internal/domain/model"
+
+	pb "route256/pkg/api/loms/v1"
+)
+
+var _ pb.LOMSServer = (*Server)(nil)
+
+type LomsService interface {
+	OrderCreate(ctx context.Context, orderReq *pb.OrderCreateRequest) (entity.ID, error)
+	OrderInfo(ctx context.Context, orderID entity.ID) (*entity.Order, error)
+	OrderPay(ctx context.Context, orderID entity.ID) error
+	OrderCancel(ctx context.Context, orderID entity.ID) error
+	StocksInfo(ctx context.Context, sku entity.Sku) (uint32, error)
+}
+
+type Server struct {
+	pb.UnimplementedLOMSServer
+
+	service LomsService
+}
+
+func NewServer(lomsService LomsService) *Server {
+	return &Server{
+		service: lomsService,
+	}
+}
+
+func mapOrderStatus(pbStatus pb.OrderStatus) (string, error) {
+	switch pbStatus {
+	case pb.OrderStatus_ORDER_STATUS_AWAITING_PAYMENT:
+		return "awaiting payment", nil
+	case pb.OrderStatus_ORDER_STATUS_CANCELLED:
+		return "cancelled", nil
+	case pb.OrderStatus_ORDER_STATUS_FAILED:
+		return "failed", nil
+	case pb.OrderStatus_ORDER_STATUS_NEW:
+		return "new", nil
+	case pb.OrderStatus_ORDER_STATUS_PAYED:
+		return "payed", nil
+	default:
+		return "", fmt.Errorf("unexpected OrderStatus: %v", pbStatus)
+	}
+}
+
+func (s *Server) OrderCreate(ctx context.Context, req *pb.OrderCreateRequest) (*pb.OrderCreateResponse, error) {
+	id, err := s.service.OrderCreate(ctx, req)
+	switch {
+	case errors.Is(err, model.ErrInvalidInput):
+		return nil, status.Error(codes.InvalidArgument, err.Error())
+	case errors.Is(err, model.ErrNotEnoughStocks):
+		return nil, status.Error(codes.FailedPrecondition, err.Error())
+	case err != nil:
+		return nil, status.Error(codes.Internal, err.Error())
+	}
+
+	return &pb.OrderCreateResponse{OrderId: int64(id)}, nil
+}
+
+func (s *Server) OrderInfo(ctx context.Context, req *pb.OrderInfoRequest) (*pb.OrderInfoResponse, error) {
+	ord, err := s.service.OrderInfo(ctx, entity.ID(req.OrderId))
+	switch {
+	case errors.Is(err, model.ErrInvalidInput):
+		return nil, status.Error(codes.InvalidArgument, err.Error())
+	case errors.Is(err, model.ErrOrderNotFound):
+		return nil, status.Error(codes.NotFound, err.Error())
+	case err != nil:
+		return nil, status.Error(codes.Internal, err.Error())
+	}
+
+	items := make([]*pb.OrderItem, len(ord.Items))
+	for i, item := range ord.Items {
+		items[i] = &pb.OrderItem{
+			Sku:   int64(item.ID),
+			Count: item.Count,
+		}
+	}
+
+	orderStatus, err := mapOrderStatus(pb.OrderStatus(pb.OrderStatus_value[ord.Status]))
+	if err != nil {
+		return nil, err
+	}
+
+	resp := &pb.OrderInfoResponse{
+		Status: orderStatus,
+		UserId: int64(ord.UserID),
+		Items:  items,
+	}
+
+	return resp, nil
+}
+
+func (s *Server) OrderPay(ctx context.Context, req *pb.OrderPayRequest) (*emptypb.Empty, error) {
+	err := s.service.OrderPay(ctx, entity.ID(req.OrderId))
+	switch {
+	case errors.Is(err, model.ErrInvalidInput):
+		return nil, status.Error(codes.InvalidArgument, err.Error())
+	case errors.Is(err, model.ErrOrderNotFound):
+		return nil, status.Error(codes.NotFound, err.Error())
+	case errors.Is(err, model.ErrOrderInvalidStatus):
+		return nil, status.Error(codes.FailedPrecondition, err.Error())
+	case err != nil:
+		return nil, status.Error(codes.Internal, err.Error())
+	}
+
+	return &emptypb.Empty{}, nil
+}
+
+func (s *Server) OrderCancel(ctx context.Context, req *pb.OrderCancelRequest) (*emptypb.Empty, error) {
+	err := s.service.OrderCancel(ctx, entity.ID(req.OrderId))
+	switch {
+	case errors.Is(err, model.ErrInvalidInput):
+		return nil, status.Error(codes.InvalidArgument, err.Error())
+	case errors.Is(err, model.ErrOrderNotFound):
+		return nil, status.Error(codes.NotFound, err.Error())
+	case errors.Is(err, model.ErrOrderInvalidStatus):
+		return nil, status.Error(codes.FailedPrecondition, err.Error())
+	case err != nil:
+		return nil, status.Error(codes.Internal, err.Error())
+	}
+
+	return &emptypb.Empty{}, nil
+}
+
+func (s *Server) StocksInfo(ctx context.Context, req *pb.StocksInfoRequest) (*pb.StocksInfoResponse, error) {
+	count, err := s.service.StocksInfo(ctx, entity.Sku(req.Sku))
+	switch {
+	case errors.Is(err, model.ErrInvalidInput):
+		return nil, status.Error(codes.InvalidArgument, err.Error())
+	case errors.Is(err, model.ErrOrderNotFound), errors.Is(err, model.ErrUnknownStock):
+		return nil, status.Error(codes.NotFound, err.Error())
+	case err != nil:
+		return nil, status.Error(codes.Internal, err.Error())
+	}
+
+	return &pb.StocksInfoResponse{Count: count}, nil
+}