Fixed the atomic transaction issue

fundraising/tests/test_webhook.py

@@ -0,0 +1,134 @@
+import json
+from unittest.mock import patch
+
+import stripe
+from django.conf import settings
+from django.core import mail
+from django.test import TestCase
+from django.urls import reverse
+from django_hosts.resolvers import reverse as django_hosts_reverse
+from stripe import util as stripe_util
+
+from ..models import DjangoHero, Donation, Payment
+
+
+class TestWebhooks(TestCase):
+    def setUp(self):
+        self.hero = DjangoHero.objects.create(email="[email protected]")
+        self.donation = Donation.objects.create(
+            donor=self.hero,
+            interval="monthly",
+            stripe_customer_id="cus_3MXPY5pvYMWTBf",
+            stripe_subscription_id="sub_3MXPaZGXvVZSrS",
+        )
+        self.url = reverse("fundraising:receive-webhook")
+
+    def stripe_data(self, filename):
+        file_path = settings.BASE_DIR.joinpath(f"fundraising/test_data/{filename}.json")
+        with file_path.open() as f:
+            data = json.load(f)
+            return stripe.util.convert_to_stripe_object(data, stripe.api_key, None)
+
+    def post_event(self):
+        return self.client.post(
+            self.url,
+            data='{"id": "evt_12345"}',
+            content_type="application/json",
+        )
+
+    @patch("stripe.Event.retrieve")
+    def test_record_payment(self, event):
+        event.return_value = self.stripe_data("invoice_succeeded")
+        response = self.post_event()
+        self.assertEqual(response.status_code, 201)
+        self.assertEqual(self.donation.payment_set.count(), 1)
+        payment = self.donation.payment_set.first()
+        self.assertEqual(payment.amount, 10)
+
+    @patch("stripe.Event.retrieve")
+    def test_subscription_cancelled(self, event):
+        event.return_value = self.stripe_data("subscription_cancelled")
+        self.post_event()
+        donation = Donation.objects.get(id=self.donation.id)
+        self.assertEqual(donation.stripe_subscription_id, "")
+        self.assertEqual(len(mail.outbox), 1)
+        expected_url = django_hosts_reverse("fundraising:index")
+        self.assertTrue(expected_url in mail.outbox[0].body)
+
+    @patch("stripe.Event.retrieve")
+    def test_payment_failed(self, event):
+        event.return_value = self.stripe_data("payment_failed")
+        self.post_event()
+        self.assertEqual(len(mail.outbox), 1)
+        expected_url = django_hosts_reverse(
+            "fundraising:manage-donations", kwargs={"hero": self.hero.id}
+        )
+        self.assertTrue(expected_url in mail.outbox[0].body)
+
+    @patch("stripe.Event.retrieve")
+    def test_no_such_event(self, event):
+        event.side_effect = stripe.error.InvalidRequestError(
+            message="No such event: evt_12345", param="id"
+        )
+        response = self.post_event()
+        self.assertEqual(response.status_code, 422)
+
+    @patch("stripe.Event.retrieve")
+    def test_empty_object(self, event):
+        event.return_value = self.stripe_data("empty_payment")
+        response = self.post_event()
+        self.assertEqual(response.status_code, 422)
+
+    @patch("stripe.Event.retrieve")
+    @patch("stripe.Customer.retrieve")
+    @patch("stripe.PaymentIntent.retrieve")
+    def test_checkout_session_completed_atomic(
+        self, mock_payment_intent, mock_customer, mock_event
+    ):
+        session_data = {
+            "id": "cs_test_123",
+            "customer": "cus_123",
+            "amount_total": 5000,  # $50.00
+            "payment_intent": "pi_123",
+            "mode": "payment",
+            "subscription": None,
+        }
+
+        # Create proper Stripe event structure
+        event_data = {
+            "type": "checkout.session.completed",
+            "data": {
+                "object": stripe_util.convert_to_stripe_object(
+                    session_data, stripe.api_key, None
+                )
+            },
+        }
+        mock_event.return_value = stripe_util.convert_to_stripe_object(
+            event_data, stripe.api_key, None
+        )
+
+        mock_customer.return_value = stripe_util.convert_to_stripe_object(
+            {
+                "id": "cus_123",
+                "email": "[email protected]",
+            },
+            stripe.api_key,
+            None,
+        )
+
+        mock_payment_intent.return_value.charges.data = [
+            stripe_util.convert_to_stripe_object({"id": "ch_123"}, stripe.api_key, None)
+        ]
+
+        # Mock Donation.objects.create to raise an exception
+        with patch("fundraising.models.Donation.objects.create") as mock_create:
+            mock_create.side_effect = Exception("Database error")
+
+            response = self.client.post(
+                self.url, data='{"id":"evt_123"}', content_type="application/json"
+            )
+
+            self.assertEqual(response.status_code, 500)
+            self.assertEqual(DjangoHero.objects.count(), 1)  # Only the one from setUp
+            self.assertEqual(Donation.objects.count(), 1)  # Only the one from setUp
+            self.assertEqual(Payment.objects.count(), 0)

fundraising/views.py

@@ -6,6 +6,7 @@
 from django.conf import settings
 from django.contrib import messages
 from django.core.mail import send_mail
+from django.db import IntegrityError, transaction
 from django.forms.models import modelformset_factory
 from django.http import HttpResponse, JsonResponse
 from django.shortcuts import get_object_or_404, redirect, render
@@ -191,14 +192,13 @@ def receive_webhook(request):
     try:
         data = json.loads(request.body.decode())
     except ValueError:
-        return HttpResponse(422)
+        return HttpResponse(status=422)
 
     # For security, re-request the event object from Stripe.
-    # TODO: Verify shared secret here?
     try:
         event = stripe.Event.retrieve(data["id"])
     except stripe.error.InvalidRequestError:
-        return HttpResponse(422)
+        return HttpResponse(status=422)
 
     return WebhookHandler(event).handle()
 
@@ -217,7 +217,15 @@ def handle(self):
         handler = handlers.get(self.event.type, lambda: HttpResponse(422))
         if not self.event.data.object:
             return HttpResponse(status=422)
-        return handler()
+        try:
+            with transaction.atomic():
+                return handler()
+        except IntegrityError as e:
+            logger.error(f"Integrity error in webhook handler: {e}")
+            return HttpResponse(status=500)
+        except Exception as e:
+            logger.error(f"Error in webhook handler: {e}")
+            return HttpResponse(status=500)
 
     def payment_succeeded(self):
         invoice = self.event.data.object
@@ -291,50 +299,61 @@ def get_donation_interval(self, session):
             return "monthly"
 
     def checkout_session_completed(self):
-        """
-        > Occurs when a Checkout Session has been successfully completed.
-        https://stripe.com/docs/api/events/types#event_types-checkout.session.completed
-        """
-        session = self.event.data.object
-        # TODO: remove stripe_version when updating account settings.
-        customer = stripe.Customer.retrieve(
-            session.customer, stripe_version="2020-08-27"
-        )
-        hero, _created = DjangoHero.objects.get_or_create(
-            stripe_customer_id=customer.id,
-            defaults={
-                "email": customer.email,
-            },
-        )
-        interval = self.get_donation_interval(session)
-        dollar_amount = decimal.Decimal(session.amount_total / 100).quantize(
-            decimal.Decimal(".01"), rounding=decimal.ROUND_HALF_UP
-        )
-        donation = Donation.objects.create(
-            donor=hero,
-            stripe_customer_id=customer.id,
-            receipt_email=customer.email,
-            subscription_amount=dollar_amount,
-            interval=interval,
-            stripe_subscription_id=session.subscription or "",
-        )
-        if interval == "onetime":
-            payment_intent = stripe.PaymentIntent.retrieve(session.payment_intent)
-            charge = payment_intent.charges.data[0]
-            donation.payment_set.create(
-                amount=dollar_amount,
-                stripe_charge_id=charge.id,
+        try:
+            """
+            > Occurs when a Checkout Session has been successfully completed.
+            https://stripe.com/docs/api/events/types#event_types-checkout.session.completed
+
+            """
+            session = self.event.data.object
+            if isinstance(session, dict):
+                session = stripe.util.convert_to_stripe_object(
+                    session, stripe.api_key, None
+                )
+
+            # TODO: remove stripe_version when updating account settings.
+            customer = stripe.Customer.retrieve(
+                session.get("customer"), stripe_version="2020-08-27"
+            )
+            hero, _created = DjangoHero.objects.get_or_create(
+                stripe_customer_id=customer.id,
+                defaults={
+                    "email": customer.email,
+                },
+            )
+            interval = self.get_donation_interval(session)
+            dollar_amount = decimal.Decimal(session.amount_total / 100).quantize(
+                decimal.Decimal(".01"), rounding=decimal.ROUND_HALF_UP
+            )
+            donation = Donation.objects.create(
+                donor=hero,
+                stripe_customer_id=customer.id,
+                receipt_email=customer.email,
+                subscription_amount=dollar_amount,
+                interval=interval,
+                stripe_subscription_id=session.subscription or "",
+            )
+            if interval == "onetime":
+                payment_intent = stripe.PaymentIntent.retrieve(session.payment_intent)
+                charge = payment_intent.charges.data[0]
+                donation.payment_set.create(
+                    amount=dollar_amount,
+                    stripe_charge_id=charge.id,
+                )
+
+            # Send an email message about managing your donation
+            message = render_to_string(
+                "fundraising/email/thank-you.html", {"donation": donation}
+            )
+            send_mail(
+                _("Thank you for your donation to the Django Software Foundation"),
+                message,
+                settings.FUNDRAISING_DEFAULT_FROM_EMAIL,
+                [donation.receipt_email],
             )
 
-        # Send an email message about managing your donation
-        message = render_to_string(
-            "fundraising/email/thank-you.html", {"donation": donation}
-        )
-        send_mail(
-            _("Thank you for your donation to the Django Software Foundation"),
-            message,
-            settings.FUNDRAISING_DEFAULT_FROM_EMAIL,
-            [donation.receipt_email],
-        )
+            return HttpResponse(status=204)
 
-        return HttpResponse(status=204)
+        except IntegrityError as e:
+            logger.error(f"Integrity error during checkout session: {e}")
+            return HttpResponse(status=500)