Send a Blinker signal when someone's subscription status changes

This is very close to the 'roles changed' signal, with the difference that
it is sent only once for multiple role changes.

pillar/api/blender_cloud/subscription.py

@@ -1,6 +1,7 @@
 import logging
 import typing
 
+import blinker
 from flask import Blueprint, Response
 import requests
 from requests.adapters import HTTPAdapter
@@ -21,6 +22,10 @@ ROLES_BID_TO_PILLAR = {
     'cloud_has_subscription': 'has_subscription',
 }
 
+user_subscription_updated = blinker.NamedSignal(
+    'user_subscription_updated',
+    'The sender is a UserClass instance, kwargs includes "revoke_roles" and "grant_roles".')
+
 
 @blueprint.route('/update-subscription')
 @authorization.require_login()
@@ -157,6 +162,14 @@ def do_update_subscription(local_user: auth.UserClass, bid_user: dict):
                         user_id, email, ', '.join(sorted(revoke_roles)))
         service.do_badger('revoke', roles=revoke_roles, user_id=user_id)
 
+    # Let the world know this user's subscription was updated.
+    final_roles = (plr_roles - revoke_roles).union(grant_roles)
+    local_user.roles = list(final_roles)
+    local_user.collect_capabilities()
+    user_subscription_updated.send(local_user,
+                                   grant_roles=grant_roles,
+                                   revoke_roles=revoke_roles)
+
     # Re-index the user in the search database.
     from pillar.api.users import hooks
     hooks.push_updated_user_to_algolia({'_id': user_id}, {})

tests/test_api/test_subscriptions.py

@@ -17,6 +17,13 @@ class RoleUpdatingTest(AbstractPillarTest):
         with self.app.test_request_context():
             self.create_standard_groups()
 
+        from pillar.api.blender_cloud import subscription as sub
+        self.user_subs_signal_calls = []
+        sub.user_subscription_updated.connect(self._user_subs_signal)
+
+    def _user_subs_signal(self, sender, **kwargs):
+        self.user_subs_signal_calls.append((sender, kwargs))
+
     def _setup_testcase(self, mocked_fetch_blenderid_user, *,
                         bid_roles: typing.Set[str]):
         import urllib.parse
@@ -54,6 +61,12 @@ class RoleUpdatingTest(AbstractPillarTest):
         user_info = self.get('/api/users/me', auth_token='my-happy-token').json()
         self.assertEqual({'subscriber', 'has_subscription'}, set(user_info['roles']))
 
+        # Check the signals
+        self.assertEqual(1, len(self.user_subs_signal_calls))
+        sender, kwargs = self.user_subs_signal_calls[0]
+        self.assertEqual({'revoke_roles': set(), 'grant_roles': {'subscriber', 'has_subscription'}},
+                         kwargs)
+
     @responses.activate
     @mock.patch('pillar.api.blender_id.fetch_blenderid_user')
     def test_store_api_role_revoke_subscriber(self, mocked_fetch_blenderid_user):
@@ -61,9 +74,9 @@ class RoleUpdatingTest(AbstractPillarTest):
                              bid_roles={'conference_speaker'})
 
         # Make sure this user is currently known as a subcriber.
-        self.create_user(roles={'subscriber'}, token='my-happy-token')
+        self.create_user(roles={'subscriber', 'has_subscription'}, token='my-happy-token')
         user_info = self.get('/api/users/me', auth_token='my-happy-token').json()
-        self.assertEqual(['subscriber'], user_info['roles'])
+        self.assertEqual({'subscriber', 'has_subscription'}, set(user_info['roles']))
 
         # And after updating, it shouldn't be.
         self.get('/api/bcloud/update-subscription', auth_token='my-happy-token',
@@ -71,6 +84,11 @@ class RoleUpdatingTest(AbstractPillarTest):
         user_info = self.get('/api/users/me', auth_token='my-happy-token').json()
         self.assertEqual([], user_info['roles'])
 
+        self.assertEqual(1, len(self.user_subs_signal_calls))
+        sender, kwargs = self.user_subs_signal_calls[0]
+        self.assertEqual({'revoke_roles': {'subscriber', 'has_subscription'}, 'grant_roles': set()},
+                         kwargs)
+
     @responses.activate
     @mock.patch('pillar.api.blender_id.fetch_blenderid_user')
     def test_bid_api_grant_demo(self, mocked_fetch_blenderid_user):
@@ -83,6 +101,10 @@ class RoleUpdatingTest(AbstractPillarTest):
         user_info = self.get('/api/users/me', auth_token='my-happy-token').json()
         self.assertEqual(['demo'], user_info['roles'])
 
+        self.assertEqual(1, len(self.user_subs_signal_calls))
+        sender, kwargs = self.user_subs_signal_calls[0]
+        self.assertEqual({'revoke_roles': set(), 'grant_roles': {'demo'}}, kwargs)
+
     @responses.activate
     @mock.patch('pillar.api.blender_id.fetch_blenderid_user')
     def test_bid_api_role_revoke_demo(self, mocked_fetch_blenderid_user):
@@ -99,3 +121,7 @@ class RoleUpdatingTest(AbstractPillarTest):
                  expected_status=204)
         user_info = self.get('/api/users/me', auth_token='my-happy-token').json()
         self.assertEqual([], user_info['roles'])
+
+        self.assertEqual(1, len(self.user_subs_signal_calls))
+        sender, kwargs = self.user_subs_signal_calls[0]
+        self.assertEqual({'revoke_roles': {'demo'}, 'grant_roles': set()}, kwargs)