Create the payment in payment_changed if payment.created hasn't arrived

askell/webhook_handlers.py

@@ -11,7 +11,10 @@ def payment_created(request, event, data):
 def payment_changed(request, event, data):
     from .models import Payment
     if event == 'payment.changed':
-        payment = Payment.objects.get(uuid=data['uuid'])
+        # payment.changed can arrive before payment.created has been handled,
+        # e.g. when a stored card is charged and settles right away.
+        payment_data = {key: data[key] for key in Payment.KEYS_TO_COPY}
+        payment, _ = Payment.objects.get_or_create(uuid=data['uuid'], defaults=payment_data)
         for attr, val in data.items():
             setattr(payment, attr, val)
         payment.save()

release.sh

@@ -1,7 +1,7 @@
 #!/usr/bin/env sh
 set -eu
 
-VERSION="0.1.25"
+VERSION="0.1.26"
 
 python3 -m twine check "dist/django_askell-${VERSION}"*
 python3 -m twine upload "dist/django_askell-${VERSION}"*

setup.py

@@ -29,7 +29,7 @@
 
 setup(
     name='django-askell',
-    version='0.1.25',
+    version='0.1.26',
     packages=find_packages(exclude=['test_project', 'test_project.*']),
     include_package_data=True,
     license='MIT',

test_project/test_app/tests.py

@@ -1,6 +1,11 @@
+import base64
+import hashlib
+import hmac
 import http.client
+import json
 from unittest.mock import patch
 
+from django.conf import settings
 from django.test import TestCase
 from django.test.client import Client
 from django.contrib.auth.models import User
@@ -180,3 +185,40 @@ def test_webhook_payment_settled(self):
         self.assertEqual(payment_count_before, payment_count_after)
         payment.refresh_from_db()
         self.assertTrue(payment.state == "settled")
+
+    def post_webhook(self, event, data):
+        body = json.dumps({'event': event, 'ref': None, 'sender': 'tumi@overcast.is', 'data': data}).encode()
+        digest = hmac.new(settings.ASKELL_WEBHOOK_SECRET.encode(), body, hashlib.sha512).digest()
+        headers = {
+            'Hook-Hmac': base64.b64encode(digest).decode(),
+            'Hook-Event': event,
+        }
+        return self.client.post('/askell/webhook/', data=body, headers=headers, content_type='application/json')
+
+    def test_webhook_payment_changed_before_payment_created(self):
+        # A payment charged straight away can settle before its payment.created
+        # webhook has been handled, so payment.changed may arrive first.
+        data = {
+            "uuid": "5f0c1e2a-7d4b-4c55-9a51-3f0f5b0c2d11",
+            "amount": "2000.0000",
+            "currency": "ISK",
+            "description": "wesd",
+            "reference": "q324erdf2",
+            "state": "settled",
+            "created_at": "2024-02-16T12:52:36.334898Z",
+            "updated_at": "2024-02-16T12:52:37.450551Z",
+            "transactions": [],
+        }
+        response = self.post_webhook('payment.changed', data)
+        self.assertEqual(response.status_code, 200)
+
+        payment = Payment.objects.get(uuid=data['uuid'])
+        self.assertEqual(payment.state, 'settled')
+        self.assertEqual(payment.reference, 'q324erdf2')
+
+        # The late payment.created must not reset the payment to pending.
+        response = self.post_webhook('payment.created', dict(data, state='pending'))
+        self.assertEqual(response.status_code, 200)
+
+        payment.refresh_from_db()
+        self.assertEqual(payment.state, 'settled')