Set postage for templated letters when the address is not from the united-kingdom.

If the address is from the united-kingdom use the postage from the template.

app/notifications/process_letter_notifications.py

@@ -14,6 +14,7 @@ def create_letter_notification(
     reply_to_text=None,
     billable_units=None,
     updated_at=None,
+    postage=None
 ):
     notification = persist_notification(
         template_id=template.id,
@@ -33,7 +34,9 @@ def create_letter_notification(
         status=status,
         reply_to_text=reply_to_text,
         billable_units=billable_units,
-        postage=letter_data.get('postage'),
+        # letter_data.get('postage') is only set for precompiled letters
+        # letters from a template will pass in 'europe' or 'rest-of-world' if None then use postage from template
+        postage=postage or letter_data.get('postage'),
         updated_at=updated_at
     )
     return notification

app/v2/notifications/post_notifications.py

@@ -339,7 +339,7 @@ def process_letter_notification(
                                                         template=template,
                                                         reply_to_text=reply_to_text)
 
-    validate_address(service, letter_data)
+    postage = validate_address(service, letter_data)
 
     test_key = api_key.key_type == KEY_TYPE_TEST
 
@@ -362,7 +362,8 @@ def process_letter_notification(
                                               api_key=api_key,
                                               status=status,
                                               reply_to_text=reply_to_text,
-                                              updated_at=updated_at
+                                              updated_at=updated_at,
+                                              postage=postage
                                               )
 
     get_pdf_for_templated_letter.apply_async(
@@ -413,6 +414,10 @@ def validate_address(service, letter_data):
         raise ValidationError(
             message='Address lines must not start with any of the following characters: @ ( ) = [ ] ” \\ / ,'
         )
+    if address.postage == 'united-kingdom':
+        return None  # use postage from template
+    else:
+        return address.postage
 
 
 def process_precompiled_letter_notifications(*, letter_data, api_key, service, template, reply_to_text):

tests/app/v2/notifications/test_post_letter_notifications.py

@@ -174,6 +174,30 @@ def test_post_letter_notification_stores_country(
         'Kronprinzenpalais\n'
         'Germany'
     )
+    assert notification.postage == 'europe'
+
+
+def test_post_letter_notification_international_sets_rest_of_world(
+        client, notify_db_session, mocker
+    ):
+        service = create_service(service_permissions=[LETTER_TYPE, INTERNATIONAL_LETTERS])
+        template = create_template(service, template_type="letter")
+        mocker.patch('app.celery.tasks.letters_pdf_tasks.get_pdf_for_templated_letter.apply_async')
+        data = {
+            'template_id': str(template.id),
+            'personalisation': {
+                'address_line_1': 'Prince Harry',
+                'address_line_2': 'Toronto',
+                'address_line_5': 'Canada',
+            }
+        }
+
+        resp_json = letter_request(client, data, service_id=service.id)
+
+        assert validate(resp_json, post_letter_response) == resp_json
+        notification = Notification.query.one()
+
+        assert notification.postage == 'rest-of-world'
 
 
 @pytest.mark.parametrize('permissions, personalisation, expected_error', (