add service

internal/repository/interfaces.go

@@ -52,6 +52,7 @@ type RequestRepository interface {
 	GetByID(ctx context.Context, id uuid.UUID) (*model.Request, error)
 	GetDetailByID(ctx context.Context, id uuid.UUID) (*model.RequestDetail, error)
 	GetUserStatistics(ctx context.Context, userID int) (requestsCount, suppliersCount, createdTZ int, err error)
+	CheckOwnership(ctx context.Context, requestID uuid.UUID, userID int) (bool, error)
 }
 
 type SupplierRepository interface {

internal/repository/request.go

@@ -214,3 +214,24 @@ func (r *requestRepository) GetUserStatistics(ctx context.Context, userID int) (
 
 	return requestsCount, suppliersCount, createdTZ, nil
 }
+
+func (r *requestRepository) CheckOwnership(ctx context.Context, requestID uuid.UUID, userID int) (bool, error) {
+	query := r.qb.Select("1").From("requests_for_suppliers").
+		Where(sq.Eq{"id": requestID, "user_id": userID})
+
+	sqlQuery, args, err := query.ToSql()
+	if err != nil {
+		return false, errs.NewInternalError(errs.DatabaseError, "failed to build query", err)
+	}
+
+	var exists int
+	err = r.pool.QueryRow(ctx, sqlQuery, args...).Scan(&exists)
+	if errors.Is(err, pgx.ErrNoRows) {
+		return false, nil
+	}
+	if err != nil {
+		return false, errs.NewInternalError(errs.DatabaseError, "failed to check ownership", err)
+	}
+
+	return true, nil
+}