Stripe: Refund webhook implemented (#32)

doc/development/api/payment.rst

@@ -61,6 +61,8 @@ The provider class
 
    .. autoattribute:: settings_form_fields
 
+   .. automethod:: settings_content_render
+
    .. automethod:: checkout_form_render
 
    .. automethod:: checkout_form

src/pretix/base/payment.py

@@ -117,6 +117,13 @@ class BasePaymentProvider:
              )),
         ])
 
+    def settings_content_render(self, request: HttpRequest) -> str:
+        """
+        When the event's administrator administrator visits the event configuration
+        page, this method is called. It may return HTML containing additional information
+        that is displayed below the form fields configured in ``settings_form_fields``.
+        """
+
     @property
     def checkout_form_fields(self) -> dict:
         """

src/pretix/control/templates/pretixcontrol/event/payment.html

@@ -22,6 +22,9 @@
 					</div>
 					<div class="panel-body">
 						{%  bootstrap_form provider.form layout='horizontal' %}
+                        {% with c=provider.settings_content %}
+                            {% if c %}{{ c|safe }}{% endif %}
+                        {% endwith %}
 					</div>
 				</div>
             {% empty %}

src/pretix/control/views/event.py

@@ -258,6 +258,7 @@ class PaymentSettings(EventPermissionRequiredMixin, TemplateView, SingleObjectMi
                     for k, v in provider.settings_form_fields.items()
                 ]
             )
+            provider.settings_content = provider.settings_content_render(self.request)
             provider.form.prepare_fields()
             providers.append(provider)
         return providers

src/pretix/plugins/stripe/payment.py

@@ -2,6 +2,7 @@ from collections import OrderedDict
 import json
 import logging
 from django.contrib import messages
+from django.core.urlresolvers import reverse
 from django.template.loader import get_template
 from django.utils.translation import ugettext_lazy as _
 from django import forms
@@ -32,6 +33,13 @@ class Stripe(BasePaymentProvider):
             ]
         )
 
+    def settings_content_render(self, request):
+        return "<div class='alert alert-info'>%s<br /><code>%s</code></div>" % (
+            _('Please configure a <a href="https://dashboard.stripe.com/account/webhooks">Stripe Webhook</a> to '
+              'the following endpoint in order to automatically cancel orders when a charges are refunded externally.'),
+            request.build_absolute_uri(reverse('plugins:stripe:webhook'))
+        )
+
     def checkout_is_valid_session(self, request):
         return request.session.get('payment_stripe_token') != ''
 
@@ -51,6 +59,7 @@ class Stripe(BasePaymentProvider):
         return template.render(ctx)
 
     def _init_api(self):
+        stripe.api_version = '2015-04-07'
         stripe.api_key = self.settings.get('secret_key')
 
     def checkout_confirm_render(self, request) -> str:
@@ -65,6 +74,11 @@ class Stripe(BasePaymentProvider):
                 amount=int(order.total * 100),
                 currency=request.event.currency.lower(),
                 source=request.session['payment_stripe_token'],
+                metadata={
+                    'order': order.identity,
+                    'event': self.event.identity,
+                    'code': order.code
+                },
                 idempotency_key=self.event.identity + order.code  # TODO: Use something better
             )
         except stripe.error.CardError as e:
@@ -83,16 +97,15 @@ class Stripe(BasePaymentProvider):
                                       'in touch with us if this problem persists.'))
             logger.error('Stripe error: %s' % str(err))
         else:
-            logger.info(charge)
             if charge.status == 'succeeded' and charge.paid:
                 try:
                     order.mark_paid('paypal', str(charge))
                     messages.success(request, _('We successfully received your payment. Thank you!'))
                 except Quota.QuotaExceededException as e:
                     messages.error(request, str(e))
-                messages.success(request, _('We successfully received your payment. Thank you!'))
             else:
                 messages.warning(request, _('Stripe reported an error: %s' % charge.failure_message))
+                logger.info('Charge failed: %s' % str(charge))
                 order = order.clone()
                 order.payment_info = str(charge)
                 order.save()

src/pretix/plugins/stripe/urls.py

@@ -0,0 +1,10 @@
+from django.conf.urls import url, include
+
+from .views import webhook
+
+
+urlpatterns = [
+    url(r'^stripe/', include([
+        url(r'^webhook/$', webhook, name='webhook'),
+    ])),
+]

src/pretix/plugins/stripe/views.py

@@ -0,0 +1,53 @@
+import json
+import logging
+from django.http import HttpResponse
+from django.views.decorators.csrf import csrf_exempt
+from django.views.decorators.http import require_POST
+from pretix.base.models import Order, Event
+from pretix.plugins.stripe.payment import Stripe
+import stripe
+
+
+logger = logging.getLogger('pretix.plugins.stripe')
+
+
+@csrf_exempt
+@require_POST
+def webhook(request):
+    event_json = json.loads(request.body.decode('utf-8'))
+    event_type = event_json['type']
+    if event_type != 'charge.refunded':
+        # Not interested
+        return HttpResponse('Event is not a refund', status=200)
+
+    charge = event_json['data']['object']
+    if charge['object'] != 'charge':
+        return HttpResponse('Object is not a charge', status=200)
+
+    metadata = charge['metadata']
+    if 'event' not in metadata:
+        return HttpResponse('Event not given', status=200)
+
+    try:
+        event = Event.objects.current.get(identity=metadata['event'])
+    except Event.DoesNotExist:
+        return HttpResponse('Event not found', status=200)
+
+    try:
+        order = Order.objects.current.get(identity=metadata['order'])
+    except Order.DoesNotExist:
+        return HttpResponse('Order not found', status=200)
+
+    prov = Stripe(event)
+    prov._init_api()
+
+    try:
+        charge = stripe.Charge.retrieve(charge['id'])
+    except stripe.error.StripeError as err:
+        logger.error('Stripe error on webhook: %s Event data: %s' % (str(err), str(event_json)))
+        return HttpResponse('StripeError', status=500)
+
+    if charge['refunds']['total_count'] > 0 and order.status == Order.STATUS_PAID:
+        order.mark_refunded()
+
+    return HttpResponse(status=200)