[hw-4] add postgres db

loms/internal/domain/repository/stocks/sqlc/db.go

@@ -0,0 +1,32 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.29.0
+
+package sqlc
+
+import (
+	"context"
+
+	"github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgconn"
+)
+
+type DBTX interface {
+	Exec(context.Context, string, ...interface{}) (pgconn.CommandTag, error)
+	Query(context.Context, string, ...interface{}) (pgx.Rows, error)
+	QueryRow(context.Context, string, ...interface{}) pgx.Row
+}
+
+func New(db DBTX) *Queries {
+	return &Queries{db: db}
+}
+
+type Queries struct {
+	db DBTX
+}
+
+func (q *Queries) WithTx(tx pgx.Tx) *Queries {
+	return &Queries{
+		db: tx,
+	}
+}

loms/internal/domain/repository/stocks/sqlc/models.go

@@ -0,0 +1,11 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.29.0
+
+package sqlc
+
+type Stock struct {
+	Sku        int64
+	TotalCount int64
+	Reserved   int64
+}

loms/internal/domain/repository/stocks/sqlc/querier.go

@@ -0,0 +1,18 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.29.0
+
+package sqlc
+
+import (
+	"context"
+)
+
+type Querier interface {
+	StockCancel(ctx context.Context, arg *StockCancelParams) (int64, error)
+	StockGetByID(ctx context.Context, sku int64) (*Stock, error)
+	StockReserve(ctx context.Context, arg *StockReserveParams) (int64, error)
+	StockReserveRemove(ctx context.Context, arg *StockReserveRemoveParams) (int64, error)
+}
+
+var _ Querier = (*Queries)(nil)

loms/internal/domain/repository/stocks/sqlc/query.sql

@@ -0,0 +1,24 @@
+-- name: StockGetByID :one
+select sku, total_count, reserved
+from stocks
+where sku = $1
+limit 1;
+
+-- name: StockReserve :execrows
+update stocks
+set reserved  = reserved  + $2
+where sku = $1
+  and total_count >= reserved + $2;
+
+-- name: StockReserveRemove :execrows
+update stocks
+set reserved = reserved - $2,
+    total_count = total_count - $2
+where sku = $1
+  and reserved >= $2 and total_count >= $2;
+
+-- name: StockCancel :execrows
+update stocks
+set reserved  = reserved  - $2
+where sku = $1
+  and reserved >= $2;

loms/internal/domain/repository/stocks/sqlc/query.sql.go

@@ -0,0 +1,85 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.29.0
+// source: query.sql
+
+package sqlc
+
+import (
+	"context"
+)
+
+const stockCancel = `-- name: StockCancel :execrows
+update stocks
+set reserved  = reserved  - $2
+where sku = $1
+  and reserved >= $2
+`
+
+type StockCancelParams struct {
+	Sku      int64
+	Reserved int64
+}
+
+func (q *Queries) StockCancel(ctx context.Context, arg *StockCancelParams) (int64, error) {
+	result, err := q.db.Exec(ctx, stockCancel, arg.Sku, arg.Reserved)
+	if err != nil {
+		return 0, err
+	}
+	return result.RowsAffected(), nil
+}
+
+const stockGetByID = `-- name: StockGetByID :one
+select sku, total_count, reserved
+from stocks
+where sku = $1
+limit 1
+`
+
+func (q *Queries) StockGetByID(ctx context.Context, sku int64) (*Stock, error) {
+	row := q.db.QueryRow(ctx, stockGetByID, sku)
+	var i Stock
+	err := row.Scan(&i.Sku, &i.TotalCount, &i.Reserved)
+	return &i, err
+}
+
+const stockReserve = `-- name: StockReserve :execrows
+update stocks
+set reserved  = reserved  + $2
+where sku = $1
+  and total_count >= reserved + $2
+`
+
+type StockReserveParams struct {
+	Sku      int64
+	Reserved int64
+}
+
+func (q *Queries) StockReserve(ctx context.Context, arg *StockReserveParams) (int64, error) {
+	result, err := q.db.Exec(ctx, stockReserve, arg.Sku, arg.Reserved)
+	if err != nil {
+		return 0, err
+	}
+	return result.RowsAffected(), nil
+}
+
+const stockReserveRemove = `-- name: StockReserveRemove :execrows
+update stocks
+set reserved = reserved - $2,
+    total_count = total_count - $2
+where sku = $1
+  and reserved >= $2 and total_count >= $2
+`
+
+type StockReserveRemoveParams struct {
+	Sku      int64
+	Reserved int64
+}
+
+func (q *Queries) StockReserveRemove(ctx context.Context, arg *StockReserveRemoveParams) (int64, error) {
+	result, err := q.db.Exec(ctx, stockReserveRemove, arg.Sku, arg.Reserved)
+	if err != nil {
+		return 0, err
+	}
+	return result.RowsAffected(), nil
+}

loms/internal/domain/repository/stocks/sqlc/repository.go

@@ -0,0 +1,137 @@
+package sqlc
+
+import (
+	"context"
+	"errors"
+	"fmt"
+
+	"github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgxpool"
+
+	"route256/loms/internal/domain/entity"
+	"route256/loms/internal/domain/model"
+	"route256/loms/internal/domain/service"
+	"route256/loms/internal/infra/postgres"
+	"route256/loms/internal/infra/tools"
+)
+
+type stockRepo struct {
+	read  *pgxpool.Pool
+	write *pgxpool.Pool
+}
+
+func NewStockRepository(write, read *pgxpool.Pool) service.StockRepository {
+	return &stockRepo{
+		read:  read,
+		write: write,
+	}
+}
+
+func (s *stockRepo) GetQuerier(ctx context.Context) *Queries {
+	tx, ok := postgres.TxFromCtx(ctx)
+	if ok {
+		return New(tx)
+	}
+
+	return New(s.write)
+}
+
+func (s *stockRepo) StockReserve(ctx context.Context, stock *entity.Stock) error {
+	querier := s.GetQuerier(ctx)
+
+	rows, err := querier.StockReserve(ctx, &StockReserveParams{
+		Sku:      int64(stock.Item.ID),
+		Reserved: int64(stock.Reserved),
+	})
+	if err != nil {
+		return fmt.Errorf("querier.StockReserve: %w", err)
+	}
+
+	if rows == 0 {
+		return model.ErrNotEnoughStocks
+	}
+
+	return nil
+}
+
+func (s *stockRepo) StockReserveRemove(ctx context.Context, stock *entity.Stock) error {
+	querier := s.GetQuerier(ctx)
+
+	rows, err := querier.StockReserveRemove(ctx, &StockReserveRemoveParams{
+		Sku:      int64(stock.Item.ID),
+		Reserved: int64(stock.Reserved),
+	})
+	if err != nil {
+		return fmt.Errorf("querier.StockReserveRemove: %w", err)
+	}
+
+	if rows > 0 {
+		return nil
+	}
+
+	_, err = querier.StockGetByID(ctx, int64(stock.Item.ID))
+	switch {
+	case errors.Is(err, pgx.ErrNoRows):
+		return model.ErrUnknownStock
+	case err != nil:
+		return fmt.Errorf("querier.StockGetByID: %w", err)
+	default:
+		return model.ErrNotEnoughStocks
+	}
+}
+
+func (s *stockRepo) StockCancel(ctx context.Context, stock *entity.Stock) error {
+	querier := s.GetQuerier(ctx)
+
+	rows, err := querier.StockCancel(ctx, &StockCancelParams{
+		Sku:      int64(stock.Item.ID),
+		Reserved: int64(stock.Reserved),
+	})
+	if err != nil {
+		return fmt.Errorf("querier.StockCancel: %w", err)
+	}
+
+	if rows > 0 {
+		return nil
+	}
+
+	_, err = querier.StockGetByID(ctx, int64(stock.Item.ID))
+	switch {
+	case errors.Is(err, pgx.ErrNoRows):
+		return model.ErrUnknownStock
+	case err != nil:
+		return fmt.Errorf("querier.StockGetByID: %w", err)
+	default:
+		return model.ErrNotEnoughStocks
+	}
+}
+
+func (s *stockRepo) StockGetByID(ctx context.Context, sku entity.Sku) (*entity.Stock, error) {
+	querier := s.GetQuerier(ctx)
+
+	stock, err := querier.StockGetByID(ctx, int64(sku))
+	switch {
+	case errors.Is(err, pgx.ErrNoRows):
+		return nil, model.ErrUnknownStock
+	case err != nil:
+		return nil, fmt.Errorf("querier.StockGetByID: %w", err)
+	default:
+		count, castErr := tools.SafeCastInt64ToUInt32(stock.TotalCount)
+		if castErr != nil {
+			return nil, castErr
+		}
+
+		reserved, castErr := tools.SafeCastInt64ToUInt32(stock.Reserved)
+		if castErr != nil {
+			return nil, castErr
+		}
+
+		return &entity.Stock{
+			Item: entity.OrderItem{
+				ID:    entity.Sku(stock.Sku),
+				Count: count,
+			},
+			Reserved: reserved,
+		}, nil
+	}
+}