feat: notification sending for printing order created

api_v1/views/printing/services.py

@@ -51,6 +51,22 @@ class PrintingOrderService:
             data['merchant'] = user.employee.merchant
         
         order = printing_models.PrintingOrder.objects.create(**data)
+
+        # domain event: printing order created
+        # handler will ensure transaction.on_commit for external side effects (e.g. WeCom notify)
+        try:
+            from printing.signals import printing_order_created
+            printing_order_created.send(
+                sender=printing_models.PrintingOrder,
+                instance=order,
+                created_by=user,
+            )
+        except Exception:
+            # signal should never break core create flow
+            import logging
+            logging.getLogger(__name__).exception(
+                "[api_v1.views.printing.services] 触发 printing_order_created signal 失败（已忽略）"
+            )
         return order
     
     @staticmethod