fix bug of rancher inventory entries - list of all cities

apps/authentication/pos/api/v1/api.py

@@ -18,12 +18,12 @@ class CityViewSet(ModelViewSet, SoftDeleteMixin):  # noqa
 
     def list(self, request, *args, **kwargs):
         """ return list of cities by province """
+        if 'province' in self.request.query_params.keys():
+            query = self.queryset.filter(province_id=int(request.GET['province']))
+        else:
+            query = self.queryset
 
-        serializer = self.serializer_class(
-            self.queryset.filter(
-                province_id=int(request.GET['province'])
-            ), many=True
-        )
+        serializer = self.serializer_class(query, many=True)
         return Response(serializer.data, status=status.HTTP_200_OK)