fix integration

backend/src/repositories/receipts.go

@@ -7,8 +7,11 @@ import (
 	"log"
 
 	"FamilyHub/src/domain"
+	"github.com/lib/pq"
 )
 
+var ErrReceiptAlreadyExists = errors.New("receipt already exists")
+
 type ReceiptsRepository interface {
 	Create(ctx context.Context, receipt *domain.Receipt) (int64, error)
 	GetByID(ctx context.Context, id int64) (*domain.Receipt, error)
@@ -129,6 +132,9 @@ func (r *ReceiptsSQLRepository) Create(ctx context.Context, receipt *domain.Rece
 
 	err = tx.QueryRowContext(ctx, query, args...).Scan(&receiptID)
 	if err != nil {
+		if isReceiptAlreadyExistsError(err) {
+			return 0, ErrReceiptAlreadyExists
+		}
 		return 0, err
 	}
 
@@ -185,6 +191,15 @@ func (r *ReceiptsSQLRepository) Create(ctx context.Context, receipt *domain.Rece
 	return receiptID, nil
 }
 
+func isReceiptAlreadyExistsError(err error) bool {
+	var pqErr *pq.Error
+	if !errors.As(err, &pqErr) {
+		return false
+	}
+
+	return pqErr.Code == "23505" && pqErr.Constraint == "receipts_receipt_number_key"
+}
+
 func (r *ReceiptsSQLRepository) GetByID(ctx context.Context, id int64) (*domain.Receipt, error) {
 
 	var receipt domain.Receipt