AP: always generate an actor for every outbound activity

for #279

common.py

@@ -14,7 +14,7 @@ from oauth_dropins.webutil.flask_util import error
 import requests
 from werkzeug.exceptions import BadGateway
 
-from models import Activity
+from models import Activity, Domain
 
 logger = logging.getLogger(__name__)
 
@@ -242,22 +242,23 @@ def send_webmentions(activity_wrapped, proxy=None, **activity_props):
         error(msg, status=int(errors[0][0] or 502))
 
 
-def postprocess_as2(activity, target=None, domain=None):
+def postprocess_as2(activity, domain=None, target=None):
     """Prepare an AS2 object to be served or sent via ActivityPub.
 
     Args:
       activity: dict, AS2 object or activity
+      domain: :class:`Domain`, required. populated into actor.id and
+        publicKey fields if needed.
       target: dict, AS2 object, optional. The target of activity's inReplyTo or
         Like/Announce/etc object, if any.
-      domain: :class:`models.Domain`, optional. populated into publicKey field
-        if provided.
     """
+    assert domain
     type = activity.get('type')
 
     # actor objects
     if type == 'Person':
-        postprocess_as2_actor(activity)
+        postprocess_as2_actor(activity, domain)
-        if not activity.get('publicKey') and domain:
+        if not activity.get('publicKey'):
             # underspecified, inferred from this issue and Mastodon's implementation:
             # https://github.com/w3c/activitypub/issues/203#issuecomment-297553229
             # https://github.com/tootsuite/mastodon/blob/bc2c263504e584e154384ecc2d804aeb1afb1ba3/app/services/activitypub/process_account_service.rb#L77
@@ -275,7 +276,7 @@ def postprocess_as2(activity, target=None, domain=None):
 
     for actor in (util.get_list(activity, 'attributedTo') +
                   util.get_list(activity, 'actor')):
-        postprocess_as2_actor(actor)
+        postprocess_as2_actor(actor, domain)
 
     # inReplyTo: singly valued, prefer id over url
     target_id = target.get('id') if target else None
@@ -344,7 +345,9 @@ def postprocess_as2(activity, target=None, domain=None):
     # to public, since Mastodon interprets to public as public, cc public as unlisted:
     # https://socialhub.activitypub.rocks/t/visibility-to-cc-mapping/284
     # https://wordsmith.social/falkreon/securing-activitypub
-    activity.setdefault('to', []).append(AS2_PUBLIC_AUDIENCE)
+    to = activity.setdefault('to', [])
+    if AS2_PUBLIC_AUDIENCE not in to:
+        to.append(AS2_PUBLIC_AUDIENCE)
 
     # wrap articles and notes in a Create activity
     if type in ('Article', 'Note'):
@@ -352,29 +355,37 @@ def postprocess_as2(activity, target=None, domain=None):
             '@context': as2.CONTEXT,
             'type': 'Create',
             'id': f'{activity["id"]}#bridgy-fed-create',
+            'actor': postprocess_as2_actor({}, domain),
             'object': activity,
         }
 
     return util.trim_nulls(activity)
 
 
-def postprocess_as2_actor(actor):
+def postprocess_as2_actor(actor, domain=None):
     """Prepare an AS2 actor object to be served or sent via ActivityPub.
 
+    Modifies actor in place.
+
     Args:
       actor: dict, AS2 actor object
+      domain: :class:`Domain`
+
+    Returns:
+      actor dict
     """
-    url = actor.get('url')
+    url = actor.get('url') or f'https://{domain.key.id()}/'
-    if url:
+    domain_str = urllib.parse.urlparse(url).netloc
-        domain = urllib.parse.urlparse(url).netloc
+
-        actor.update({
+    actor.setdefault('id', request.host_url + domain_str)
-            'id': request.host_url + domain,
+    actor.update({
-            'url': redirect_wrap(url),
+        'url': redirect_wrap(url),
-            'preferredUsername': domain,
+        'preferredUsername': domain_str,
-        })
+    })
 
     # required by pixelfed. https://github.com/snarfed/bridgy-fed/issues/39
     actor.setdefault('summary', '')
+    return actor
 
 
 def redirect_wrap(url):

redirect.py

@@ -51,9 +51,11 @@ def redir(to):
                    util.domain_from_link(to, minimize=False),
                    urllib.parse.urlparse(to).hostname))
     for domain in domains:
-        if domain and Domain.get_by_id(domain):
+        if domain:
-            logger.info(f'Found Domain for domain {domain}')
+            entity = Domain.get_by_id(domain)
-            break
+            if entity:
+                logger.info(f'Found Domain for domain {domain}')
+                break
     else:
         logger.info(f'No user found for any of {domains}; returning 404')
         abort(404)
@@ -62,24 +64,29 @@ def redir(to):
     # priorities.
     if request.headers.get('Accept') in (common.CONTENT_TYPE_AS2,
                                          common.CONTENT_TYPE_AS2_LD):
-        return convert_to_as2(to)
+        return convert_to_as2(to, entity)
 
     # redirect
     logger.info(f'redirecting to {to}')
     return redirect(to, code=301)
 
 
-def convert_to_as2(url):
+def convert_to_as2(url, domain):
     """Fetch a URL as HTML, convert it to AS2, and return it.
 
     Currently mainly for Pixelfed.
     https://github.com/snarfed/bridgy-fed/issues/39
+
+    Args:
+      url: str
+      domain: :class:`Domain`
     """
     mf2 = util.fetch_mf2(url)
     entry = mf2util.find_first_entry(mf2, ['h-entry'])
     logger.info(f"Parsed mf2 for {mf2['url']}: {json_dumps(entry, indent=2)}")
 
-    obj = common.postprocess_as2(as2.from_as1(microformats2.json_to_object(entry)))
+    obj = common.postprocess_as2(as2.from_as1(microformats2.json_to_object(entry)),
+                                 domain)
     logger.info(f'Returning: {json_dumps(obj, indent=2)}')
 
     return obj, {

tests/test_common.py

@@ -9,6 +9,7 @@ from werkzeug.exceptions import BadGateway
 
 from app import app
 import common
+from models import Domain
 from . import testutil
 
 HTML = requests_response('<html></html>', headers={
@@ -67,11 +68,56 @@ class CommonTest(testutil.TestCase):
 
     def test_postprocess_as2_multiple_in_reply_tos(self):
         with app.test_request_context('/'):
-            self.assertEqual({
+            self.assert_equals({
                 'id': 'http://localhost/r/xyz',
                 'inReplyTo': 'foo',
                 'to': [common.AS2_PUBLIC_AUDIENCE],
             }, common.postprocess_as2({
                 'id': 'xyz',
                 'inReplyTo': ['foo', 'bar'],
-            }))
+            }, domain=Domain(id='foo.com')))
+
+    def test_postprocess_as2_actor_attributedTo(self):
+        with app.test_request_context('/'):
+            self.assert_equals({
+                'actor': {
+                    'id': 'baj',
+                    'preferredUsername': 'foo.com',
+                    'url': 'http://localhost/r/https://foo.com/',
+                },
+                'attributedTo': [{
+                    'id': 'bar',
+                    'preferredUsername': 'foo.com',
+                    'url': 'http://localhost/r/https://foo.com/',
+                }, {
+                    'id': 'baz',
+                    'preferredUsername': 'foo.com',
+                    'url': 'http://localhost/r/https://foo.com/',
+                }],
+                'to': [common.AS2_PUBLIC_AUDIENCE],
+            }, common.postprocess_as2({
+                'attributedTo': [{'id': 'bar'}, {'id': 'baz'}],
+                'actor': {'id': 'baj'},
+            }, domain=Domain(id='foo.com')))
+
+    def test_postprocess_as2_note(self):
+        with app.test_request_context('/'):
+            self.assert_equals({
+                '@context': 'https://www.w3.org/ns/activitystreams',
+                'id': 'http://localhost/r/xyz#bridgy-fed-create',
+                'type': 'Create',
+                'actor': {
+                    'id': 'http://localhost/foo.com',
+                    'url': 'http://localhost/r/https://foo.com/',
+                    'preferredUsername': 'foo.com'
+                },
+                'object': {
+                    'id': 'http://localhost/r/xyz',
+                    'type': 'Note',
+                    'to': [common.AS2_PUBLIC_AUDIENCE],
+                },
+            }, common.postprocess_as2({
+                'id': 'xyz',
+                'type': 'Note',
+            }, domain=Domain(id='foo.com')))
+

tests/test_webmention.py

@@ -158,6 +158,11 @@ class WebmentionTest(testutil.TestCase):
             '@context': 'https://www.w3.org/ns/activitystreams',
             'type': 'Create',
             'id': 'http://localhost/r/http://a/reply#bridgy-fed-create',
+            'actor': {
+                'id': 'http://localhost/a',
+                'url': 'http://localhost/r/https://a/',
+                'preferredUsername': 'a',
+            },
             'object': {
                 '@context': 'https://www.w3.org/ns/activitystreams',
                 'type': 'Note',
@@ -240,6 +245,11 @@ class WebmentionTest(testutil.TestCase):
             '@context': 'https://www.w3.org/ns/activitystreams',
             'type': 'Create',
             'id': 'http://localhost/r/http://orig/post#bridgy-fed-create',
+            'actor': {
+                'id': 'http://localhost/orig',
+                'url': 'http://localhost/r/https://orig/',
+                'preferredUsername': 'orig',
+            },
             'object': {
                 '@context': 'https://www.w3.org/ns/activitystreams',
                 'type': 'Note',