Add atomic transaction in counters

counter/templates/counter/user_account.jinja

@@ -6,6 +6,7 @@
 
 {% block infos %}
 <h3>{% trans %}User account{% endtrans %}</h3>
+<p>{% trans %}Amount: {% endtrans %}{{ customer.amount }} €</p>
 <p>{{ customer.refillings.all() }}</p>
 <p>{{ customer.buyings.all() }}</p>
 {% endblock %}

counter/views.py

@@ -10,6 +10,7 @@ from django.utils import timezone
 from django import forms
 from django.utils.translation import ugettext_lazy as _
 from django.conf import settings
+from django.db import DataError, transaction
 
 import re
 
@@ -218,6 +219,7 @@ class CounterClick(DetailView):
 
     def finish(self, request):
         """ Finish the click session, and validate the basket """
+        with transaction.atomic():
             if self.is_barman_price():
                 seller = self.customer.user
             else:
@@ -230,6 +232,8 @@ class CounterClick(DetailView):
                     uprice = p.special_selling_price
                 else:
                     uprice = p.selling_price
+                if uprice * infos['qty'] > self.customer.amount:
+                    raise DataError(_("You have not enough money to buy all the basket"))
                 request.session['last_basket'].append("%d x %s" % (infos['qty'], p.name))
                 s = Selling(product=p, counter=self.object, unit_price=uprice,
                        quantity=infos['qty'], seller=seller, customer=self.customer)