Fixed updating of stripe donations

Author: bmispelon

fundraising/forms.py

@@ -1,5 +1,6 @@
 import stripe
 from django import forms
+from django.db import transaction
 from django.utils.safestring import mark_safe
 from django.utils.translation import gettext_lazy as _
 from django_recaptcha.fields import ReCaptchaField
@@ -154,17 +155,15 @@ class Meta:
         model = Donation
         fields = ("subscription_amount", "interval")
 
+    @transaction.atomic()
     def save(self, commit=True, *args, **kwargs):
         donation = super().save(commit=commit)
-        interval = self.cleaned_data.get("interval")
-        amount = self.cleaned_data.get("subscription_amount")
 
         # Send data to Stripe
-        customer = stripe.Customer.retrieve(donation.stripe_customer_id)
-        subscription = customer.subscriptions.retrieve(donation.stripe_subscription_id)
+        subscription = stripe.Subscription.retrieve(donation.stripe_subscription_id)
         # TODO: Setting the plan is deprecated — use Price API instead.
-        subscription.plan = interval
-        subscription.quantity = int(amount)
+        subscription.plan = self.cleaned_data["interval"]
+        subscription.quantity = int(self.cleaned_data["subscription_amount"])
 
         subscription.save()
 

fundraising/tests/test_forms.py

@@ -3,7 +3,8 @@
 from django.test import TestCase
 from django_recaptcha.client import RecaptchaResponse
 
-from ..forms import PaymentForm
+from ..forms import DonationForm, PaymentForm
+from ..models import DjangoHero, Donation
 
 
 class TestPaymentForm(TestCase):
@@ -44,3 +45,27 @@ def test_captcha_token_required(self):
         )
         self.assertFalse(form.is_valid())
         self.assertIn("captcha", form.errors)
+
+    @patch("fundraising.forms.stripe.Subscription.retrieve", side_effect=KeyError)
+    def test_donation_form_save_atomic(self, *mocks):
+        """
+        A stripe error in save() should rollback any change made to the Donation
+        """
+        donation = Donation.objects.create(
+            interval="monthly",
+            subscription_amount=50,
+            donor=DjangoHero.objects.create(),
+        )
+        form = DonationForm(
+            instance=donation,
+            data={"subscription_amount": 25, "interval": "yearly"},
+        )
+
+        # Save the form, this will trigger a KeyError but we catch it and move on
+        self.assertTrue(form.is_valid())
+        self.assertRaises(KeyError, form.save)
+
+        # The donation should not have been updated with new data
+        donation.refresh_from_db()
+        self.assertEqual(donation.interval, "monthly")
+        self.assertEqual(donation.subscription_amount, 50)