authorization: pass and accept authed_as in receive task handler

for #566

atproto.py

@@ -432,6 +432,7 @@ def poll_notifications():
             common.create_task(queue='receive', obj=obj.key.urlsafe(),
                                # TODO: should this be the receiving user?
                                # or the sending user?
-                               user=user.key.urlsafe())
+                               user=user.key.urlsafe(),
+                               authed_as=notif['author']['did'])
 
     return 'OK'

protocol.py

@@ -1134,10 +1134,13 @@ class Protocol:
 def receive_task():
     """Task handler for a newly received :class:`models.Object`.
 
+    Calls :meth:`Protocol.receive` with the form parameters.
+
     Parameters:
       obj (google.cloud.ndb.key.Key): :class:`models.Object` to handle
       user (google.cloud.ndb.key.Key): :class:`models.User` this activity is on
         behalf of. This user will be loaded into ``g.user``
+      authed_as (str): passed to :meth:`Protocol.receive`
 
     TODO: migrate incoming webmentions and AP inbox deliveries to this. The
     difficulty is that parts of :meth:`protocol.Protocol.receive` depend on
@@ -1146,15 +1149,16 @@ def receive_task():
     :meth:`Protocol.receive` now loads), HTTP request details, etc. See stash
     for attempt at this for :class:`web.Web`.
     """
-    logger.info(f'Params: {list(request.form.items())}')
+    form = request.form.to_dict()
+    logger.info(f'Params: {list(form.items())}')
 
-    obj = ndb.Key(urlsafe=request.form['obj']).get()
+    obj = ndb.Key(urlsafe=form.pop('obj')).get()
     assert obj
-    if user_key := request.form.get('user'):
+    if user_key := form.pop('user', None):
         g.user = ndb.Key(urlsafe=user_key).get()
 
     try:
-        return PROTOCOLS[obj.source_protocol].receive(obj)
+        return PROTOCOLS[obj.source_protocol].receive(obj, **form)
     except ValueError as e:
         logger.warning(e, exc_info=True)
         error(e, status=304)

tests/test_atproto.py

@@ -577,14 +577,17 @@ class ATProtoTest(TestCase):
         like_obj = Object.get_by_id('at://did:plc:d/app.bsky.feed.like/123')
         self.assertEqual(like, like_obj.bsky)
         self.assert_task(mock_create_task, 'receive', '/queue/receive',
-                         obj=like_obj.key.urlsafe(), user=user_a.key.urlsafe())
+                         obj=like_obj.key.urlsafe(), user=user_a.key.urlsafe(),
+                         authed_as='did:plc:eve')
 
         reply_obj = Object.get_by_id('at://did:plc:d/app.bsky.feed.post/456')
         self.assertEqual(reply, reply_obj.bsky)
         self.assert_task(mock_create_task, 'receive', '/queue/receive',
-                         obj=reply_obj.key.urlsafe(), user=user_a.key.urlsafe())
+                         obj=reply_obj.key.urlsafe(), user=user_a.key.urlsafe(),
+                         authed_as='did:plc:eve')
 
         follow_obj = Object.get_by_id('at://did:plc:d/app.bsky.graph.follow/789')
         self.assertEqual(follow, follow_obj.bsky)
         self.assert_task(mock_create_task, 'receive', '/queue/receive',
-                         obj=follow_obj.key.urlsafe(), user=user_c.key.urlsafe())
+                         obj=follow_obj.key.urlsafe(), user=user_c.key.urlsafe(),
+                         authed_as='did:plc:a')

tests/test_protocol.py

@@ -1386,7 +1386,7 @@ class ProtocolReceiveTest(TestCase):
                            )
         self.assertEqual(2, Follower.query().count())
 
-    def test_task_handler(self):
+    def test_receive_task_handler(self):
         note = {
             'id': 'fake:post',
             'objectType': 'note',
@@ -1399,6 +1399,25 @@ class ProtocolReceiveTest(TestCase):
         obj = Object.get_by_id('fake:post#bridgy-fed-create')
         self.assertEqual('ignored', obj.status)
 
+    def test_receive_task_handler_authed_as(self):
+        note = {
+            'id': 'fake:post',
+            'objectType': 'note',
+            'author': 'fake:other',
+        }
+        obj = self.store_object(id='fake:post', our_as1=note,
+                                source_protocol='fake')
+
+        with self.assertLogs() as logs:
+            self.client.post('/queue/receive', data={
+                'obj': obj.key.urlsafe(),
+                'authed_as': 'fake:eve',
+            })
+
+        self.assertIn(
+            "WARNING:protocol:actor fake:other isn't authed user fake:eve",
+            logs.output)
+
     def test_g_user_opted_out(self):
         self.make_followers()
         g.user.obj.our_as1 = {'summary': '#nobot'}