addingding
diff --git a/Collapse file
‎src/allocation/handlers.py‎
Copy file name to clipboardExpand all lines: src/allocation/handlers.py
+12-3Lines changed: 12 additions & 3 deletions b/Collapse file
‎src/allocation/handlers.py‎
Copy file name to clipboardExpand all lines: src/allocation/handlers.py
+12-3Lines changed: 12 additions & 3 deletions
diff --git a/Collapse file
‎src/allocation/messagebus.py‎
Copy file name to clipboardExpand all lines: src/allocation/messagebus.py
+2Lines changed: 2 additions & 0 deletions b/Collapse file
‎src/allocation/messagebus.py‎
Copy file name to clipboardExpand all lines: src/allocation/messagebus.py
+2Lines changed: 2 additions & 0 deletions
@@ -1,12 +1,11 @@
 from __future__ import annotations
-import typing
+from typing import TYPE_CHECKING
 from allocation import events, email, exceptions, model
 from allocation.model import OrderLine
-if typing.TYPE_CHECKING:
+if TYPE_CHECKING:
     from allocation import unit_of_work
 
 
-
 def add_batch(
         event: events.BatchCreated, uow: unit_of_work.AbstractUnitOfWork
 ):
@@ -34,6 +33,16 @@ def allocate(
         return batchref
 
 
+
+def change_batch_quantity(
+        event: events.BatchQuantityChanged, uow: unit_of_work.AbstractUnitOfWork
+):
+    with uow:
+        product = uow.products.get_by_batchref(batchref=event.ref)
+        product.change_batch_quantity(ref=event.ref, qty=event.qty)
+        uow.commit()
+
+
 # pylint: disable=unused-argument
 
 def send_out_of_stock_notification(
 
@@ -16,6 +16,8 @@ def handle(event: events.Event, uow: unit_of_work.AbstractUnitOfWork):
 
 HANDLERS = {
     events.BatchCreated: [handlers.add_batch],
+    events.BatchQuantityChanged: [handlers.change_batch_quantity],
     events.AllocationRequired: [handlers.allocate],
     events.OutOfStock: [handlers.send_out_of_stock_notification],
+
 }  # type: Dict[Type[events.Event], List[Callable]]