Proof of concept for auto-accepting invites

This is for demonstration purposes only. In practice this would actually look up the right profile and use the right thing, not to mention be in a more reasonable location.

synapse/handlers/federation.py

@@ -56,7 +56,7 @@ from synapse.replication.http.federation import (
 )
 from synapse.replication.http.membership import ReplicationUserJoinedLeftRoomRestServlet
 from synapse.state import StateResolutionStore, resolve_events_with_store
-from synapse.types import UserID, create_requester, get_domain_from_id
+from synapse.types import UserID, get_domain_from_id, create_requester
 from synapse.util import logcontext, unwrapFirstError
 from synapse.util.async_helpers import Linearizer
 from synapse.util.distributor import user_joined_room
@@ -1409,8 +1409,37 @@ class FederationHandler(BaseHandler):
         context = yield self.state_handler.compute_event_context(event)
         yield self.persist_events_and_notify([(event, context)])
 
+        sender = UserID.from_string(event.sender)
+        target = UserID.from_string(event.state_key)
+        if (sender.localpart == target.localpart):
+            logcontext.run_in_background(
+                self._auto_accept_invite,
+                sender, target, event.room_id,
+            )
+
         defer.returnValue(event)
 
+    @defer.inlineCallbacks
+    def _auto_accept_invite(self, sender, target, room_id):
+        joined = False
+        for attempt in range(0, 10):
+            try:
+                yield self.hs.get_room_member_handler().update_membership(
+                    requester=create_requester(target.to_string()),
+                    target=target,
+                    room_id=room_id,
+                    action="join",
+                )
+                joined = True
+                break
+            except Exception:
+                # We're going to retry, but we should log the error
+                logger.exception("Error auto-accepting invite on attempt %d" % attempt)
+                yield self.hs.get_clock().sleep(1)
+        if not joined:
+            logger.error("Giving up on trying to auto-accept invite: too many attempts")
+
+
     @defer.inlineCallbacks
     def do_remotely_reject_invite(self, target_hosts, room_id, user_id):
         origin, event = yield self._make_and_verify_event(

synapse/handlers/room_member.py

@@ -29,7 +29,7 @@ import synapse.server
 import synapse.types
 from synapse.api.constants import EventTypes, Membership
 from synapse.api.errors import AuthError, Codes, SynapseError
-from synapse.types import RoomID, UserID
+from synapse.types import RoomID, UserID, RoomAlias
 from synapse.util.async_helpers import Linearizer
 from synapse.util.distributor import user_joined_room, user_left_room
 
@@ -416,6 +416,7 @@ class RoomMemberHandler(object):
                 ret = yield self._remote_join(
                     requester, remote_room_hosts, room_id, target, content
                 )
+                self._send_merged_user_invites(requester, room_id)
                 defer.returnValue(ret)
 
         elif effective_membership_state == Membership.LEAVE:
@@ -450,8 +451,34 @@ class RoomMemberHandler(object):
             prev_events_and_hashes=prev_events_and_hashes,
             content=content,
         )
+        self._send_merged_user_invites(requester, room_id)
         defer.returnValue(res)
 
+    @defer.inlineCallbacks
+    def _send_merged_user_invites(self, requester, room_id):
+        profile_alias = "#_profile_" + requester.user.localpart + ":" + self.hs.hostname
+        profile_alias = RoomAlias.from_string(profile_alias)
+        profile_room_id, remote_room_hosts = yield self.lookup_room_alias(profile_alias)
+        if profile_room_id:
+            linked_accounts = yield self.state_handler.get_current_state(
+                room_id=profile_room_id.to_string(),
+                event_type="m.linked_accounts",
+                state_key="",
+            )
+            if not linked_accounts or not linked_accounts.content['all_children']:
+                return
+            for child_id in linked_accounts.content['all_children']:
+                child = UserID.from_string(child_id)
+                if self.hs.is_mine(child) or child_id == requester.user.to_string():
+                    # TODO: Handle auto-invite for local users (not a priority)
+                    continue
+                self.update_membership(
+                    requester=requester,
+                    target=child,
+                    room_id=room_id,
+                    action="invite",
+                )
+
     @defer.inlineCallbacks
     def send_membership_event(
             self,