Add support for Move activity

app/activitypub.py

@@ -277,6 +277,13 @@ async def get_object(activity: RawObject) -> RawObject:
         raise ValueError(f"Unexpected object {raw_activity_object}")
 
 
+def get_object_id(activity: RawObject) -> str:
+    if "object" not in activity:
+        raise ValueError(f"No object in {activity}")
+
+    return get_id(activity["object"])
+
+
 def wrap_object(activity: RawObject) -> RawObject:
     # TODO(tsileo): improve Create VS Update with a `update=True` flag
     if "updated" in activity:

app/boxes.py

@@ -208,6 +208,11 @@ async def send_announce(db_session: AsyncSession, ap_object_id: str) -> None:
 
 
 async def send_follow(db_session: AsyncSession, ap_actor_id: str) -> None:
+    await _send_follow(db_session, ap_actor_id)
+    await db_session.commit()
+
+
+async def _send_follow(db_session: AsyncSession, ap_actor_id: str) -> None:
     actor = await fetch_actor(db_session, ap_actor_id)
 
     follow_id = allocate_outbox_id()
@@ -226,10 +231,16 @@ async def send_follow(db_session: AsyncSession, ap_actor_id: str) -> None:
         raise ValueError("Should never happen")
 
     await new_outgoing_activity(db_session, actor.inbox_url, outbox_object.id)
-    await db_session.commit()
+
+    # Caller should commit
 
 
 async def send_undo(db_session: AsyncSession, ap_object_id: str) -> None:
+    await _send_undo(db_session, ap_object_id)
+    await db_session.commit()
+
+
+async def _send_undo(db_session: AsyncSession, ap_object_id: str) -> None:
     outbox_object_to_undo = await get_outbox_object_by_ap_id(db_session, ap_object_id)
     if not outbox_object_to_undo:
         raise ValueError(f"{ap_object_id} not found in the outbox")
@@ -309,7 +320,7 @@ async def send_undo(db_session: AsyncSession, ap_object_id: str) -> None:
     else:
         raise ValueError("Should never happen")
 
-    await db_session.commit()
+    # called should commit
 
 
 async def fetch_conversation_root(
@@ -1139,6 +1150,54 @@ async def _handle_undo_activity(
     # commit will be perfomed in save_to_inbox
 
 
+async def _handle_move_activity(
+    db_session: AsyncSession,
+    from_actor: models.Actor,
+    move_activity: models.InboxObject,
+) -> None:
+    logger.info("Processing Move activity")
+
+    # Ensure the object matches the actor
+    old_actor_id = ap.get_object_id(move_activity.ap_object)
+    if old_actor_id != from_actor.ap_id:
+        logger.warning(
+            f"Object does not match the actor: {old_actor_id}/{from_actor.ap_id}"
+        )
+        return None
+
+    # Fetch the target account
+    new_actor_id = move_activity.ap_object.get("target")
+    if not new_actor_id:
+        logger.warning("Missing target")
+        return None
+
+    new_actor = await fetch_actor(db_session, new_actor_id)
+
+    # Ensure the target account references the old account
+    if old_actor_id not in (aks := new_actor.ap_actor.get("alsoKnownAs", [])):
+        logger.warning(
+            f"New account does not have have an alias for the old account: {aks}"
+        )
+        return None
+
+    # Unfollow the old account
+    following = (
+        await db_session.execute(
+            select(models.Following)
+            .where(models.Following.ap_actor_id == old_actor_id)
+            .options(joinedload(models.Following.outbox_object))
+        )
+    ).scalar_one_or_none()
+    if not following:
+        logger.warning("Not following the Move actor")
+        return
+
+    await _send_undo(db_session, following.outbox_object.ap_id)
+
+    # Follow the new one
+    await _send_follow(db_session, new_actor_id)
+
+
 async def _handle_update_activity(
     db_session: AsyncSession,
     from_actor: models.Actor,
@@ -1576,6 +1635,8 @@ async def save_to_inbox(
         await _handle_read_activity(db_session, actor, inbox_object)
     elif activity_ro.ap_type == "Update":
         await _handle_update_activity(db_session, actor, inbox_object)
+    elif activity_ro.ap_type == "Move":
+        await _handle_move_activity(db_session, actor, inbox_object)
     elif activity_ro.ap_type == "Delete":
         await _handle_delete_activity(
             db_session,

app/main.py

@@ -76,8 +76,8 @@ _RESIZED_CACHE: MutableMapping[tuple[str, int], tuple[bytes, str, Any]] = LFUCac
 # TODO(ts):
 #
 # Next:
-# - empty recipients for Share on "was not in the inbox" object
+# - fix issue with followers from a blocked server (skip it?)
-# - support Move
+# - CORS webfinger endpoint
 # - support actor delete
 # - allow to share old notes
 # - allow to interact with object not in anybox (i.e. like from a lookup)

tests/factories.py

@@ -68,6 +68,21 @@ def build_accept_activity(
     }
 
 
+def build_move_activity(
+    from_remote_actor: actor.RemoteActor,
+    for_remote_object: actor.RemoteActor,
+    outbox_public_id: str | None = None,
+) -> ap.RawObject:
+    return {
+        "@context": ap.AS_CTX,
+        "type": "Move",
+        "id": from_remote_actor.ap_id + "/move/" + (outbox_public_id or uuid4().hex),
+        "actor": from_remote_actor.ap_id,
+        "object": from_remote_actor.ap_id,
+        "target": for_remote_object.ap_id,
+    }
+
+
 def build_note_object(
     from_remote_actor: actor.RemoteActor,
     outbox_public_id: str | None = None,
@@ -123,11 +138,13 @@ class RemoteActorFactory(factory.Factory):
             "base_url",
             "username",
             "public_key",
+            "also_known_as",
         )
 
     class Params:
         icon_url = None
         summary = "I like unit tests"
+        also_known_as: list[str] = []
 
     ap_actor = factory.LazyAttribute(
         lambda o: {
@@ -152,6 +169,7 @@ class RemoteActorFactory(factory.Factory):
                 "owner": o.base_url,
                 "publicKeyPem": o.public_key,
             },
+            "alsoKnownAs": o.also_known_as,
         }
     )
 
@@ -240,3 +258,8 @@ class InboxObjectFactory(factory.alchemy.SQLAlchemyModelFactory):
 class FollowerFactory(factory.alchemy.SQLAlchemyModelFactory):
     class Meta(BaseModelMeta):
         model = models.Follower
+
+
+class FollowingFactory(factory.alchemy.SQLAlchemyModelFactory):
+    class Meta(BaseModelMeta):
+        model = models.Following

tests/test_inbox.py

@@ -21,6 +21,7 @@ from tests.utils import run_async
 from tests.utils import setup_inbox_delete
 from tests.utils import setup_remote_actor
 from tests.utils import setup_remote_actor_as_follower
+from tests.utils import setup_remote_actor_as_following
 
 
 async def _process_next_incoming_activity(db_session: AsyncSession) -> None:
@@ -353,3 +354,72 @@ def test_inbox__actor_is_blocked(
         )
         == 0
     )
+
+
+def test_inbox__move_activity(
+    db: Session,
+    client: TestClient,
+    respx_mock: respx.MockRouter,
+) -> None:
+    # Given a remote actor
+    ra = setup_remote_actor(respx_mock)
+
+    # Which is followed by the local actor
+    following = setup_remote_actor_as_following(ra)
+    old_actor = following.actor
+    assert old_actor
+    assert following.outbox_object
+    follow_id = following.outbox_object.ap_id
+
+    # When receiving a Move activity
+    new_ra = setup_remote_actor(
+        respx_mock,
+        base_url="https://new-account.com",
+        also_known_as=[ra.ap_id],
+    )
+    move_activity = RemoteObject(
+        factories.build_move_activity(ra, new_ra),
+        ra,
+    )
+
+    with mock_httpsig_checker(ra):
+        response = client.post(
+            "/inbox",
+            headers={"Content-Type": ap.AS_CTX},
+            json=move_activity.ap_object,
+        )
+
+    # Then the server returns a 204
+    assert response.status_code == 202
+
+    run_async(_process_next_incoming_activity)
+
+    # And the Move activity was saved in the inbox
+    inbox_activity = db.execute(select(models.InboxObject)).scalar_one()
+    assert inbox_activity.ap_type == "Move"
+    assert inbox_activity.actor_id == old_actor.id
+
+    # And the following actor was deleted
+    assert db.scalar(select(func.count(models.Following.id))) == 0
+
+    # And the follow was undone
+    assert (
+        db.scalar(
+            select(func.count(models.OutboxObject.id)).where(
+                models.OutboxObject.ap_type == "Undo",
+                models.OutboxObject.activity_object_ap_id == follow_id,
+            )
+        )
+        == 1
+    )
+
+    # And the new account was followed
+    assert (
+        db.scalar(
+            select(func.count(models.OutboxObject.id)).where(
+                models.OutboxObject.ap_type == "Follow",
+                models.OutboxObject.activity_object_ap_id == new_ra.ap_id,
+            )
+        )
+        == 1
+    )

tests/utils.py

@@ -40,11 +40,16 @@ def generate_admin_session_cookies() -> dict[str, Any]:
     return {"session": session_serializer.dumps({"is_logged_in": True})}
 
 
-def setup_remote_actor(respx_mock: respx.MockRouter) -> actor.RemoteActor:
+def setup_remote_actor(
+    respx_mock: respx.MockRouter,
+    base_url="https://example.com",
+    also_known_as=None,
+) -> actor.RemoteActor:
     ra = factories.RemoteActorFactory(
-        base_url="https://example.com",
+        base_url=base_url,
         username="toto",
         public_key="pk",
+        also_known_as=also_known_as if also_known_as else [],
     )
     respx_mock.get(ra.ap_id + "/outbox").mock(
         return_value=httpx.Response(
@@ -86,6 +91,30 @@ def setup_remote_actor_as_follower(ra: actor.RemoteActor) -> models.Follower:
     return follower
 
 
+def setup_remote_actor_as_following(ra: actor.RemoteActor) -> models.Following:
+    actor = factories.ActorFactory.from_remote_actor(ra)
+
+    follow_id = uuid4().hex
+    follow_from_outbox = RemoteObject(
+        factories.build_follow_activity(
+            from_remote_actor=LOCAL_ACTOR,
+            for_remote_actor=ra,
+            outbox_public_id=follow_id,
+        ),
+        LOCAL_ACTOR,
+    )
+    outbox_object = factories.OutboxObjectFactory.from_remote_object(
+        follow_id, follow_from_outbox
+    )
+
+    following = factories.FollowingFactory(
+        outbox_object_id=outbox_object.id,
+        actor_id=actor.id,
+        ap_actor_id=actor.ap_id,
+    )
+    return following
+
+
 def setup_inbox_delete(
     actor: models.Actor, deleted_object_ap_id: str
 ) -> models.InboxObject: