chore: initial commit

internal/svc/warehouse/warehouse.go

@@ -0,0 +1,168 @@
+// Copyright (C) 2024 Declan Teevan
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package warehouse
+
+import (
+	"context"
+
+	"github.com/bufbuild/protovalidate-go"
+	"github.com/rs/zerolog/log"
+	"google.golang.org/protobuf/types/known/emptypb"
+
+	"github.com/hexolan/stocklet/internal/pkg/errors"
+	"github.com/hexolan/stocklet/internal/pkg/messaging"
+	commonpb "github.com/hexolan/stocklet/internal/pkg/protogen/common/v1"
+	eventpb "github.com/hexolan/stocklet/internal/pkg/protogen/events/v1"
+	pb "github.com/hexolan/stocklet/internal/pkg/protogen/warehouse/v1"
+)
+
+// Interface for the service
+type WarehouseService struct {
+	pb.UnimplementedWarehouseServiceServer
+
+	store StorageController
+	pbVal *protovalidate.Validator
+}
+
+// Interface for database methods
+// Flexibility for implementing seperate controllers for different databases (e.g. Postgres, MongoDB, etc)
+type StorageController interface {
+	GetProductStock(ctx context.Context, productId string) (*pb.ProductStock, error)
+	GetReservation(ctx context.Context, reservationId string) (*pb.Reservation, error)
+
+	CreateProductStock(ctx context.Context, productId string, startingQuantity int32) error
+
+	ReserveOrderStock(ctx context.Context, orderId string, orderMetadata EventOrderMetadata, productQuantities map[string]int32) error
+	ReturnReservedOrderStock(ctx context.Context, orderId string) error
+	ConsumeReservedOrderStock(ctx context.Context, orderId string) error
+}
+
+// Interface for event consumption
+// Flexibility for seperate controllers for different messaging systems (e.g. Kafka, NATS, etc)
+type ConsumerController interface {
+	messaging.ConsumerController
+
+	Attach(svc pb.WarehouseServiceServer)
+}
+
+// Create the shipping service
+func NewWarehouseService(cfg *ServiceConfig, store StorageController) *WarehouseService {
+	// Initialise the protobuf validator
+	pbVal, err := protovalidate.New()
+	if err != nil {
+		log.Panic().Err(err).Msg("failed to initialise protobuf validator")
+	}
+
+	// Initialise the service
+	return &WarehouseService{
+		store: store,
+		pbVal: pbVal,
+	}
+}
+
+func (svc WarehouseService) ServiceInfo(ctx context.Context, req *commonpb.ServiceInfoRequest) (*commonpb.ServiceInfoResponse, error) {
+	return &commonpb.ServiceInfoResponse{
+		Name:          "warehouse",
+		Source:        "https://github.com/hexolan/stocklet",
+		SourceLicense: "AGPL-3.0",
+	}, nil
+}
+
+func (svc WarehouseService) ViewProductStock(ctx context.Context, req *pb.ViewProductStockRequest) (*pb.ViewProductStockResponse, error) {
+	// Validate the request args
+	if err := svc.pbVal.Validate(req); err != nil {
+		// Provide the validation error to the user.
+		return nil, errors.NewServiceError(errors.ErrCodeInvalidArgument, "invalid request: "+err.Error())
+	}
+
+	// Get stock from db
+	stock, err := svc.store.GetProductStock(ctx, req.ProductId)
+	if err != nil {
+		return nil, err
+	}
+
+	return &pb.ViewProductStockResponse{Stock: stock}, nil
+}
+
+func (svc WarehouseService) ViewReservation(ctx context.Context, req *pb.ViewReservationRequest) (*pb.ViewReservationResponse, error) {
+	// Validate the request args
+	if err := svc.pbVal.Validate(req); err != nil {
+		// Provide the validation error to the user.
+		return nil, errors.NewServiceError(errors.ErrCodeInvalidArgument, "invalid request: "+err.Error())
+	}
+
+	// Get reservation from db
+	reservation, err := svc.store.GetReservation(ctx, req.ReservationId)
+	if err != nil {
+		return nil, err
+	}
+
+	return &pb.ViewReservationResponse{Reservation: reservation}, nil
+}
+
+func (svc WarehouseService) ProcessProductCreatedEvent(ctx context.Context, req *eventpb.ProductCreatedEvent) (*emptypb.Empty, error) {
+	err := svc.store.CreateProductStock(ctx, req.ProductId, 0)
+	if err != nil {
+		return nil, errors.WrapServiceError(errors.ErrCodeExtService, "error processing event", err)
+	}
+
+	return &emptypb.Empty{}, nil
+}
+
+func (svc WarehouseService) ProcessOrderPendingEvent(ctx context.Context, req *eventpb.OrderPendingEvent) (*emptypb.Empty, error) {
+	err := svc.store.ReserveOrderStock(
+		ctx,
+		req.OrderId,
+		EventOrderMetadata{
+			CustomerId: req.CustomerId,
+			ItemsPrice: req.ItemsPrice,
+			TotalPrice: req.TotalPrice,
+		},
+		req.ItemQuantities,
+	)
+	if err != nil {
+		return nil, errors.WrapServiceError(errors.ErrCodeExtService, "error processing event", err)
+	}
+
+	return &emptypb.Empty{}, nil
+}
+
+func (svc WarehouseService) ProcessShipmentAllocationEvent(ctx context.Context, req *eventpb.ShipmentAllocationEvent) (*emptypb.Empty, error) {
+	if req.Type == eventpb.ShipmentAllocationEvent_TYPE_FAILED {
+		err := svc.store.ReturnReservedOrderStock(ctx, req.OrderId)
+		if err != nil {
+			return nil, errors.WrapServiceError(errors.ErrCodeExtService, "error processing event", err)
+		}
+	}
+
+	return &emptypb.Empty{}, nil
+}
+
+func (svc WarehouseService) ProcessPaymentProcessedEvent(ctx context.Context, req *eventpb.PaymentProcessedEvent) (*emptypb.Empty, error) {
+	if req.Type == eventpb.PaymentProcessedEvent_TYPE_FAILED {
+		err := svc.store.ReturnReservedOrderStock(ctx, req.OrderId)
+		if err != nil {
+			return nil, errors.WrapServiceError(errors.ErrCodeExtService, "error processing event", err)
+		}
+	} else if req.Type == eventpb.PaymentProcessedEvent_TYPE_SUCCESS {
+		err := svc.store.ConsumeReservedOrderStock(ctx, req.OrderId)
+		if err != nil {
+			return nil, errors.WrapServiceError(errors.ErrCodeExtService, "error processing event", err)
+		}
+	}
+
+	return &emptypb.Empty{}, nil
+}