Add admin bill generation endpoint

uncloud_pay/serializers.py

@@ -72,6 +72,7 @@ class OrderSerializer(serializers.ModelSerializer):
         model = Order
         fields = ['uuid', 'owner', 'description', 'creation_date', 'starting_date', 'ending_date',
                 'bill', 'recurring_period', 'recurring_price', 'one_time_price', 'replaced_by']
+        read_only_fields = ['replaced_by']
 
 
 ###

uncloud_pay/views.py

@@ -302,6 +302,22 @@ class AdminBillViewSet(BillViewSet):
         serializer = self.get_serializer(unpaid_bills, many=True)
         return Response(serializer.data)
 
+    @action(detail=False, methods=['post'])
+    def generate(self, request):
+        users = get_user_model().objects.all()
+
+        generated_bills = []
+        for user in users:
+            now = timezone.now()
+            generated_bills = generated_bills + Bill.generate_for(
+                    year=now.year,
+                    month=now.month,
+                    user=user)
+
+        return Response(
+                map(lambda b: b.reference, generated_bills),
+                status=status.HTTP_200_OK)
+
 class AdminOrderViewSet(mixins.ListModelMixin,
         mixins.RetrieveModelMixin,
         mixins.CreateModelMixin,