Update method to delete notifications that are a week old, to look at the days of retention set for the service.

If the service does not have the days of retention set, then use 7 days.
Added a method to get days of retention for a service and notificaiton type

app/dao/notifications_dao.py

@@ -42,7 +42,8 @@ from app.models import (
     NOTIFICATION_PERMANENT_FAILURE,
     NOTIFICATION_SENT,
     SMS_TYPE,
-    EMAIL_TYPE
+    EMAIL_TYPE,
+    ServiceDataRetention
 )
 
 from app.dao.dao_utils import transactional
@@ -310,10 +311,23 @@ def _filter_query(query, filter_dict=None):
 @statsd(namespace="dao")
 @transactional
 def delete_notifications_created_more_than_a_week_ago_by_type(notification_type):
+    flexible_data_retention = ServiceDataRetention.query.filter(
+        ServiceDataRetention.notification_type == notification_type
+    ).all()
+    deleted = 0
+    for f in flexible_data_retention:
+        days_of_retention = convert_utc_to_bst(datetime.utcnow()).date() - timedelta(days=f.days_of_retention)
+        deleted += db.session.query(Notification).filter(
+            func.date(Notification.created_at) < days_of_retention,
+            Notification.notification_type == f.notification_type,
+            Notification.service_id == f.service_id
+        ).delete(synchronize_session='fetch')
     seven_days_ago = convert_utc_to_bst(datetime.utcnow()).date() - timedelta(days=7)
+    services_with_data_retention = [x.service_id for x in flexible_data_retention]
     deleted = db.session.query(Notification).filter(
         func.date(Notification.created_at) < seven_days_ago,
         Notification.notification_type == notification_type,
+        Notification.service_id.notin_(services_with_data_retention)
     ).delete(synchronize_session='fetch')
     return deleted
 

app/dao/service_data_retention_dao.py

@@ -20,6 +20,14 @@ def fetch_service_data_retention(service_id):
     return data_retention_list
 
 
+def fetch_service_data_retention_by_notification_type(service_id, notification_type):
+    data_retention_list = ServiceDataRetention.query.filter_by(
+        service_id=service_id,
+        notification_type=notification_type
+    ).first()
+    return data_retention_list
+
+
 @transactional
 def insert_service_data_retention(service_id, notification_type, days_of_retention):
     new_data_retention = ServiceDataRetention(service_id=service_id,