fix(payments): keep callback redirect resilient to Redis

apps/payments/tests/integration/test_payments.py

@@ -1,6 +1,8 @@
 import pytest
 import json
+import redis
 from datetime import timedelta
+from kombu.exceptions import OperationalError
 from django.utils import timezone
 from core.authentication import create_jwt_token
 from apps.events.models import Event, Registration
@@ -171,6 +173,40 @@ class TestPaymentsAPIIntegrationTests:
         assert f'/events/{self.event.slug}/registration?payment_id={payment.id}' in response.url
         assert 'status=' not in response.url
 
+    def test_callback_redirects_if_payment_notification_redis_is_unavailable(self, mocker):
+        mock_post = mocker.patch('apps.payments.api.views.requests.post')
+        self.user.is_mobile_verified = True
+        self.user.save(update_fields=['is_mobile_verified'])
+        payment = Payment.objects.create(
+            user=self.user,
+            event=self.event,
+            base_amount=self.event.price,
+            amount=self.event.price,
+            status=Payment.OrderStatusChoices.PENDING,
+            authority='AUTH-REDIS-DOWN',
+        )
+        mock_post.return_value.json.return_value = {
+            'data': {'code': 100, 'ref_id': 'REF-REDIS-DOWN'}
+        }
+        mocker.patch(
+            'apps.payments.api.views.notify_user',
+            side_effect=redis.exceptions.ConnectionError('Redis unavailable'),
+        )
+        mocker.patch(
+            'apps.payments.api.views.send_critical_sms.delay',
+            side_effect=OperationalError('Celery broker unavailable'),
+        )
+
+        response = self.client.get(
+            '/api/payments/callback',
+            {'Authority': payment.authority, 'Status': 'OK'},
+        )
+
+        payment.refresh_from_db()
+        assert response.status_code == 302
+        assert f'/events/{self.event.slug}/registration?payment_id={payment.id}' in response.url
+        assert payment.status == Payment.OrderStatusChoices.PAID
+
     def test_callback_failure_redirects_failed(self, mocker):
         mock_post = mocker.patch('apps.payments.api.views.requests.post')
         payment = Payment.objects.create(user=self.user, event=self.event, base_amount=self.event.price, amount=self.event.price, status=Payment.OrderStatusChoices.PENDING, authority='AUTH456')