feat: send trial cancelation confirmation braze email

Author: jajjibhai008

enterprise_access/apps/customer_billing/stripe_event_handlers.py

@@ -240,25 +240,31 @@ def subscription_updated(event: stripe.Event) -> None:
             )
 
         # Handle trial subscription cancellation
-        # TODO: Check that status wasn't already canceled to avoid duplicate emails.
-        # This will be easier to implement once StripeEventSummary changes land,
-        # which will provide easier querying of prior subscription states.
-        if subscription.get("status") == "canceled":
-            trial_end = subscription.get("trial_end")
-            if trial_end:
-                logger.info(
-                    f"Queuing trial cancellation email for subscription {subscription.id}, "
-                    f"checkout_intent_id={checkout_intent_id}"
-                )
-
-                # Queue the async task to send the email
-                send_trial_cancellation_email_task.delay(
-                    checkout_intent_id=checkout_intent.id,
-                    trial_end_timestamp=trial_end,
-                )
+        # Check if status changed to canceled to avoid duplicate emails
+        current_status = subscription.get("status")
+        if current_status == "canceled":
+            prior_status = getattr(checkout_intent.previous_summary(event), 'subscription_status', None)
+
+            # Only send email if status changed from non-canceled to canceled
+            if prior_status != 'canceled':
+                trial_end = subscription.get("trial_end")
+                if trial_end:
+                    logger.info(
+                        f"Subscription {subscription.id} status changed from '{prior_status}' to 'canceled'. "
+                        f"Queuing trial cancellation email for checkout_intent_id={checkout_intent_id}"
+                    )
+
+                    send_trial_cancellation_email_task.delay(
+                        checkout_intent_id=checkout_intent.id,
+                        trial_end_timestamp=trial_end,
+                    )
+                else:
+                    logger.info(
+                        f"Subscription {subscription.id} canceled but has no trial_end, skipping cancellation email"
+                    )
             else:
                 logger.info(
-                    f"Subscription {subscription.id} canceled but has no trial_end, skipping cancellation email"
+                    f"Subscription {subscription.id} already canceled (status unchanged), skipping cancellation email"
                 )
 
     @on_stripe_event("customer.subscription.deleted")

enterprise_access/apps/customer_billing/tasks.py

@@ -253,7 +253,6 @@ def send_trial_cancellation_email_task(
                 lms_user_id=admin.get("lms_user_id"),
             )
             recipients.append(recipient)
-
         except Exception as exc:  # pylint: disable=broad-exception-caught
             logger.warning(
                 "Failed to create Braze recipient for admin email %s: %s",

enterprise_access/apps/customer_billing/tests/test_stripe_event_handlers.py

@@ -2,6 +2,7 @@
 Unit tests for Stripe event handlers.
 """
 from contextlib import nullcontext
+from datetime import timedelta
 from random import randint
 from typing import Type, cast
 from unittest import mock
@@ -10,6 +11,7 @@
 import stripe
 from django.contrib.auth.models import AbstractUser
 from django.test import TestCase
+from django.utils import timezone
 
 from enterprise_access.apps.core.tests.factories import UserFactory
 from enterprise_access.apps.customer_billing.constants import CheckoutIntentState
@@ -66,6 +68,8 @@ def tearDown(self):
     def _create_mock_stripe_event(self, event_type, event_data):
         """Helper to create a mock Stripe event."""
         mock_event = mock.MagicMock(spec=stripe.Event)
+        created_at = timezone.now() - timedelta(seconds=randint(1, 30))
+        mock_event.created = int(created_at.timestamp())
         mock_event.type = event_type
         numeric_id = str(randint(1, 100000)).zfill(6)
         mock_event.id = f'evt_test_{event_type.replace(".", "_")}_{numeric_id}'