Deal with empty quantities in place order

A user may add a value in place of the "0" and then delete it,
so it will send an empty string to the server.

copanier/__init__.py

@@ -5,7 +5,7 @@ from time import perf_counter
 import ujson as json
 import minicli
 from jinja2 import Environment, PackageLoader, select_autoescape
-from roll import Roll, Response
+from roll import Roll, Response, HttpError
 from roll.extensions import cors, options, traceback, simple_server, static
 
 from . import config, reports, session, utils, emails, loggers
@@ -222,7 +222,10 @@ async def place_order(request, response, id):
         form = request.form
         order = Order(paid=form.bool("paid", False))
         for product in delivery.products:
-            quantity = form.int(product.ref, 0)
+            try:
+                quantity = form.int(product.ref, 0)
+            except HttpError:
+                continue
             if quantity:
                 order.products[product.ref] = ProductOrder(wanted=quantity)
         if not delivery.orders:

tests/test_views.py

@@ -76,6 +76,15 @@ async def test_place_empty_order_should_delete_previous(client, delivery):
     assert not delivery.orders
 
 
+async def test_place_order_with_empty_string(client, delivery):
+    delivery.persist()
+    body = {"123": ""}  # User deleted the field value.
+    resp = await client.post(f"/livraison/{delivery.id}/commander", body=body)
+    assert resp.status == 302
+    delivery = Delivery.load(id=delivery.id)
+    assert not delivery.orders
+
+
 async def test_change_paid_status_when_placing_order(client, delivery):
     delivery.persist()
     body = {