3 files changed, 30 insertions, 1 deletions
diff --git a/synapse/handlers/_base.py b/synapse/handlers/_base.py
index 5613bd2059..bdade98bf7 100644
--- a/synapse/handlers/_base.py
+++ b/synapse/handlers/_base.py
@@ -293,6 +293,12 @@ class BaseHandler(object):
 
         if event.type == EventTypes.Member:
             if event.content["membership"] == Membership.INVITE:
+                def is_inviter_member_event(e):
+                    return (
+                        e.type == EventTypes.Member and
+                        e.sender == event.sender
+                    )
+
                 event.unsigned["invite_room_state"] = [
                     {
                         "type": e.type,
@@ -306,7 +312,7 @@ class BaseHandler(object):
                         EventTypes.CanonicalAlias,
                         EventTypes.RoomAvatar,
                         EventTypes.Name,
-                    )
+                    ) or is_inviter_member_event(e)
                 ]
 
                 invitee = UserID.from_string(event.state_key)
diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index f8959e5d82..6d155d57e7 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -349,3 +349,18 @@ class RegistrationHandler(BaseHandler):
 
     def auth_handler(self):
         return self.hs.get_handlers().auth_handler
+
+    @defer.inlineCallbacks
+    def guest_access_token_for(self, medium, address, inviter_user_id):
+        access_token = yield self.store.get_3pid_guest_access_token(medium, address)
+        if access_token:
+            defer.returnValue(access_token)
+
+        _, access_token = yield self.register(
+            generate_token=True,
+            make_guest=True
+        )
+        access_token = yield self.store.save_or_get_3pid_guest_access_token(
+            medium, address, access_token, inviter_user_id
+        )
+        defer.returnValue(access_token)
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index eb9700a35b..d2de23a6cc 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -848,6 +848,13 @@ class RoomMemberHandler(BaseHandler):
                 user.
         """
 
+        registration_handler = self.hs.get_handlers().registration_handler
+        guest_access_token = yield registration_handler.guest_access_token_for(
+            medium=medium,
+            address=address,
+            inviter_user_id=inviter_user_id,
+        )
+
         is_url = "%s%s/_matrix/identity/api/v1/store-invite" % (
             id_server_scheme, id_server,
         )
@@ -864,6 +871,7 @@ class RoomMemberHandler(BaseHandler):
                 "sender": inviter_user_id,
                 "sender_display_name": inviter_display_name,
                 "sender_avatar_url": inviter_avatar_url,
+                "guest_access_token": guest_access_token,
             }
         )
         # TODO: Check for success