Removing platform_default as a concept. No service actually wants to send letters with the default hm-government logo so we are going to remove it as a constraint.

However, until we can create a letter without a logo, we will still default to hm-government, because the dvla_organisation is set on the service.
This does simplify the code.
Also removed the inserts to letter_branding in the data migration file, because we can deploy this before the rest of the work is finished. But we will need to do it later.

tests/app/celery/test_letters_pdf_tasks.py

@@ -203,7 +203,7 @@ def test_create_letters_gets_the_right_logo_when_service_has_dvla_logo(
 def test_create_letters_gets_the_right_logo_when_service_has_letter_branding_logo(
         notify_api, mocker, sample_letter_notification
 ):
-    letter_branding = create_letter_branding(name='test brand', filename='test-brand', platform_default=False)
+    letter_branding = create_letter_branding(name='test brand', filename='test-brand')
     sample_letter_notification.service.letter_branding = letter_branding
     mock_get_letters_pdf = mocker.patch('app.celery.letters_pdf_tasks.get_letters_pdf', return_value=(b'\x00\x01', 1))
     mocker.patch('app.letters.utils.s3upload')

tests/app/dao/test_letter_branding_dao.py

@@ -1,5 +1,5 @@
 from app.dao.letter_branding_dao import (
-    dao_get_letter_branding_or_platform_default,
+    dao_get_letter_branding_by_domain,
     dao_get_all_letter_branding,
     dao_create_letter_branding,
     dao_update_letter_branding
@@ -8,36 +8,29 @@ from app.models import LetterBranding
 from tests.app.db import create_letter_branding
 
 
-def test_dao_get_letter_branding_or_platform_default_returns_platform_default_if_domain_is_none(notify_db_session):
-    create_letter_branding()
-    result = dao_get_letter_branding_or_platform_default(domain=None)
-    assert result.filename == 'hm-government'
+def test_dao_get_letter_branding_by_domain_returns_none_if_no_matching_domains(notify_db_session):
+    result = dao_get_letter_branding_by_domain(domain="test.domain")
+    assert not result
 
 
-def test_dao_get_letter_branding_or_platform_default_if_domain_is_not_associated_with_a_brand(notify_db_session):
-    create_letter_branding()
-    result = dao_get_letter_branding_or_platform_default(domain="foo.bar")
-    assert result.filename == 'hm-government'
-
-
-def test_dao_get_letter_branding_or_platform_default_returns_correct_brand_for_domain(notify_db_session):
-    create_letter_branding()
+def test_dao_get_letter_branding_by_domain_returns_correct_brand_for_domain(notify_db_session):
+    create_letter_branding(domain='gov.uk')
     test_domain_branding = create_letter_branding(
-        name='test domain', filename='test-domain', domain='test.domain', platform_default=False
+        name='test domain', filename='test-domain', domain='test.domain'
     )
-    result = dao_get_letter_branding_or_platform_default(domain='test.domain')
+    result = dao_get_letter_branding_by_domain(domain='test.domain')
     result == test_domain_branding
 
 
 def test_dao_get_all_letter_branding(notify_db_session):
-    platform_default = create_letter_branding()
+    hm_gov = create_letter_branding()
     test_domain = create_letter_branding(
-        name='test domain', filename='test-domain', domain='test.domain', platform_default=False
+        name='test domain', filename='test-domain', domain='test.domain'
     )
 
     results = dao_get_all_letter_branding()
 
-    assert platform_default in results
+    assert hm_gov in results
     assert test_domain in results
     assert len(results) == 2
 
@@ -61,7 +54,6 @@ def test_dao_create_letter_branding(notify_db_session):
     assert new_letter_branding.name == data['name']
     assert new_letter_branding.domain == data['domain']
     assert new_letter_branding.filename == data['name']
-    assert not new_letter_branding.platform_default
 
 
 def test_dao_update_letter_branding(notify_db_session):

tests/app/dao/test_services_dao.py

@@ -106,7 +106,7 @@ def test_create_service_with_letter_branding(notify_db_session):
     user = create_user()
     create_letter_branding()
     letter_branding = create_letter_branding(
-        name='test domain', filename='test-domain', domain='test.domain', platform_default=False
+        name='test domain', filename='test-domain', domain='test.domain'
     )
     assert Service.query.count() == 0
     service = Service(name="service_name",

tests/app/db.py

@@ -727,11 +727,10 @@ def create_template_folder(service, name='foo', parent=None):
     return tf
 
 
-def create_letter_branding(name='HM Government', filename='hm-government', domain=None, platform_default=True):
+def create_letter_branding(name='HM Government', filename='hm-government', domain=None):
     test_domain_branding = LetterBranding(name=name,
                                           filename=filename,
                                           domain=domain,
-                                          platform_default=platform_default
                                           )
     db.session.add(test_domain_branding)
     db.session.commit()

tests/app/letter_branding/test_letter_branding_rest.py

@@ -1,6 +1,5 @@
 import json
 
-import pytest
 
 from app.models import LetterBranding
 from tests import create_authorization_header
@@ -8,19 +7,21 @@ from tests.app.db import create_letter_branding
 
 
 def test_get_all_letter_brands(client, notify_db_session):
-    platform_default = create_letter_branding()
+    hm_gov = create_letter_branding()
     test_domain_branding = create_letter_branding(
-        name='test domain', filename='test-domain', domain='test.domain', platform_default=False
+        name='test domain', filename='test-domain', domain='test.domain'
     )
     response = client.get('/letter-branding', headers=[create_authorization_header()])
     assert response.status_code == 200
     json_response = json.loads(response.get_data(as_text=True))
     assert len(json_response) == 2
     for brand in json_response:
-        if brand['id'] == platform_default:
-            platform_default.serialize() == brand
+        if brand['id'] == str(hm_gov.id):
+            assert hm_gov.serialize() == brand
+        elif brand['id'] == str(test_domain_branding.id):
+            assert test_domain_branding.serialize() == brand
         else:
-            test_domain_branding.serialize() == brand
+            assert False
 
 
 def test_create_letter_branding(client, notify_db_session):
@@ -42,26 +43,6 @@ def test_create_letter_branding(client, notify_db_session):
     assert letter_brand.name == form['name']
     assert letter_brand.domain == form['domain']
     assert letter_brand.filename == form['filename']
-    assert not letter_brand.platform_default
-
-
-def test_create_letter_branding_returns_400_if_platform_default_is_passed_in_the_form(client, notify_db_session):
-    form = {
-        'name': 'super brand',
-        'domain': 'super.brand',
-        'filename': 'super-brand',
-        'platform_default': True
-    }
-
-    response = client.post(
-        '/letter-branding',
-        data=json.dumps(form),
-        headers=[('Content-Type', 'application/json'), create_authorization_header()],
-    )
-    assert response.status_code == 400
-    json_resp = json.loads(response.get_data(as_text=True))
-    assert json_resp['errors'][0]['message'] == \
-        "Additional properties are not allowed (platform_default was unexpected)"
 
 
 def test_create_letter_branding_returns_400_if_name_already_exists(client, notify_db_session):
@@ -102,5 +83,4 @@ def test_update_letter_branding_returns_400_when_integrity_error_is_thrown(
 
     assert response.status_code == 400
     json_resp = json.loads(response.get_data(as_text=True))
-    # Why is this name and not domain? copied this pattern from email_branding
     assert json_resp['message'] == {"name": ["Duplicate domain 'duplicate'"]}

tests/app/service/test_rest.py

@@ -219,7 +219,6 @@ def test_get_service_by_id_should_404_if_no_service_for_user(notify_api, sample_
 
 
 def test_create_service(client, sample_user):
-    platform_default = create_letter_branding()
     data = {
         'name': 'created service',
         'user_id': str(sample_user.id),
@@ -243,6 +242,7 @@ def test_create_service(client, sample_user):
     assert not json_resp['data']['research_mode']
     assert json_resp['data']['dvla_organisation'] == '001'
     assert json_resp['data']['rate_limit'] == 3000
+    assert json_resp['data']['letter_branding'] is None
 
     service_db = Service.query.get(json_resp['data']['id'])
     assert service_db.name == 'created service'
@@ -261,12 +261,11 @@ def test_create_service(client, sample_user):
     service_sms_senders = ServiceSmsSender.query.filter_by(service_id=service_db.id).all()
     assert len(service_sms_senders) == 1
     assert service_sms_senders[0].sms_sender == current_app.config['FROM_NUMBER']
-    assert json_resp['data']['letter_branding'] == str(platform_default.id)
 
 
 def test_create_service_with_domain_sets_letter_branding(client, sample_user):
     letter_branding = create_letter_branding(
-        name='test domain', filename='test-domain', domain='test.domain', platform_default=False
+        name='test domain', filename='test-domain', domain='test.domain'
     )
     data = {
         'name': 'created service',
@@ -286,6 +285,7 @@ def test_create_service_with_domain_sets_letter_branding(client, sample_user):
         headers=headers)
     json_resp = resp.json
     assert resp.status_code == 201
+    assert json_resp['data']['dvla_organisation'] == '001'
     assert json_resp['data']['letter_branding'] == str(letter_branding.id)
     assert json_resp['data']['letter_logo_filename'] == str(letter_branding.filename)
 
@@ -310,7 +310,7 @@ def test_create_service_when_letter_branding_is_empty(client, sample_user):
         headers=headers)
     json_resp = resp.json
     assert resp.status_code == 201
-    assert not json_resp['data']['letter_branding']
+    assert json_resp['data']['letter_branding'] is None
     assert json_resp['data']['letter_logo_filename'] == 'hm-government'
 
 
@@ -318,7 +318,7 @@ def test_get_service_by_id_returns_letter_branding_not_dvla_organisation(
         client, sample_service
 ):
     letter_branding = create_letter_branding(
-        name='test domain', filename='test-domain', domain='test.domain', platform_default=False
+        name='test domain', filename='test-domain', domain='test.domain'
     )
     data = {
         'letter_branding': str(letter_branding.id)
@@ -334,6 +334,7 @@ def test_get_service_by_id_returns_letter_branding_not_dvla_organisation(
     assert json_resp['data']['name'] == sample_service.name
     assert json_resp['data']['id'] == str(sample_service.id)
     assert json_resp['data']['dvla_organisation'] == '001'
+    assert json_resp['data']['letter_branding'] == str(letter_branding.id)
     assert json_resp['data']['letter_logo_filename'] == 'test-domain'
 
 
@@ -515,7 +516,7 @@ def test_update_service(client, notify_db, sample_service):
 
 
 def test_update_service_letter_branding(client, notify_db, sample_service):
-    letter_branding = create_letter_branding(name='test brand', filename='test-brand', platform_default=False)
+    letter_branding = create_letter_branding(name='test brand', filename='test-brand')
     data = {
         'letter_branding': str(letter_branding.id)
     }
@@ -532,6 +533,35 @@ def test_update_service_letter_branding(client, notify_db, sample_service):
     assert result['data']['letter_branding'] == str(letter_branding.id)
 
 
+def test_update_service_remove_letter_branding(client, notify_db, sample_service):
+    letter_branding = create_letter_branding(name='test brand', filename='test-brand')
+    sample_service
+    data = {
+        'letter_branding': str(letter_branding.id)
+    }
+
+    auth_header = create_authorization_header()
+
+    client.post(
+        '/service/{}'.format(sample_service.id),
+        data=json.dumps(data),
+        headers=[('Content-Type', 'application/json'), auth_header]
+    )
+
+    data = {
+        'letter_branding': None
+    }
+    resp = client.post(
+        '/service/{}'.format(sample_service.id),
+        data=json.dumps(data),
+        headers=[('Content-Type', 'application/json'), auth_header]
+    )
+
+    result = resp.json
+    assert resp.status_code == 200
+    assert result['data']['letter_branding'] is None
+
+
 def test_update_service_remove_email_branding(admin_request, notify_db, sample_service):
     brand = EmailBranding(colour='#000000', logo='justice-league.png', name='Justice League')
     sample_service.email_branding = brand