Tweak and add test for OrganisationsClient.remove_user_from_organisation

This stops adding the current user to the data sent to the API when
removing a user from an organisation. API only needs to know the
organisation_id and the id of the user we want to remove from
the organisation, so we don't need to pass through the id of the
current user too.

The other change made is to clear the user cache of the user who has
been removed from the org. We don't need to clear any of the organisation
caches, since these values don't contain lists of users for the orgs.

app/notify_client/organisations_api_client.py

@@ -3,7 +3,7 @@ from itertools import chain
 from notifications_python_client.errors import HTTPError
 
 from app.extensions import redis_client
-from app.notify_client import NotifyAdminAPIClient, _attach_current_user, cache
+from app.notify_client import NotifyAdminAPIClient, cache
 
 
 class OrganisationsClient(NotifyAdminAPIClient):
@@ -76,10 +76,9 @@ class OrganisationsClient(NotifyAdminAPIClient):
     def get_organisation_services(self, org_id):
         return self.get(url="/organisations/{}/services".format(org_id))
 
+    @cache.delete('user-{user_id}')
     def remove_user_from_organisation(self, org_id, user_id):
-        endpoint = '/organisations/{}/users/{}'.format(org_id, user_id)
-        data = _attach_current_user({})
-        return self.delete(endpoint, data)
+        return self.delete(f'/organisations/{org_id}/users/{user_id}')
 
     def get_services_and_usage(self, org_id, year):
         return self.get(

tests/app/notify_client/test_organisation_client.py

@@ -229,3 +229,19 @@ def test_update_service_organisation_deletes_cache(mocker, fake_uuid):
         url='/organisations/{}/service'.format(fake_uuid),
         data=ANY
     )
+
+
+def test_remove_user_from_organisation_deletes_user_cache(mocker):
+    mock_redis_delete = mocker.patch('app.extensions.RedisClient.delete')
+    mock_delete = mocker.patch('app.notify_client.organisations_api_client.OrganisationsClient.delete')
+
+    org_id = 'abcd-1234'
+    user_id = 'efgh-5678'
+
+    organisations_client.remove_user_from_organisation(
+        org_id=org_id,
+        user_id=user_id,
+    )
+
+    assert mock_redis_delete.call_args_list == [call(f'user-{user_id}')]
+    mock_delete.assert_called_with(f'/organisations/{org_id}/users/{user_id}')