From ee42a5513e020424daa736962fee7fb69bd2373a Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <richard@matrix.org>
Date: Tue, 28 Jan 2020 11:02:55 +0000
Subject: Factor out a `copy_power_levels_contents` method

I'm going to need another copy (hah!) of this.
---
 synapse/events/utils.py | 37 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

(limited to 'synapse/events/utils.py')

diff --git a/synapse/events/utils.py b/synapse/events/utils.py
index 07d1c5bcf0..be57c6d9be 100644
--- a/synapse/events/utils.py
+++ b/synapse/events/utils.py
@@ -12,8 +12,9 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-
+import collections
 import re
+from typing import Mapping, Union
 
 from six import string_types
 
@@ -422,3 +423,37 @@ class EventClientSerializer(object):
         return yieldable_gather_results(
             self.serialize_event, events, time_now=time_now, **kwargs
         )
+
+
+def copy_power_levels_contents(
+    old_power_levels: Mapping[str, Union[int, Mapping[str, int]]]
+):
+    """Copy the content of a power_levels event, unfreezing frozendicts along the way
+
+    Raises:
+        TypeError if the input does not look like a valid power levels event content
+    """
+    if not isinstance(old_power_levels, collections.Mapping):
+        raise TypeError("Not a valid power-levels content: %r" % (old_power_levels,))
+
+    power_levels = {}
+    for k, v in old_power_levels.items():
+
+        if isinstance(v, int):
+            power_levels[k] = v
+            continue
+
+        if isinstance(v, collections.Mapping):
+            power_levels[k] = h = {}
+            for k1, v1 in v.items():
+                # we should only have one level of nesting
+                if not isinstance(v1, int):
+                    raise TypeError(
+                        "Invalid power_levels value for %s.%s: %r" % (k, k1, v)
+                    )
+                h[k1] = v1
+            continue
+
+        raise TypeError("Invalid power_levels value for %s: %r" % (k, v))
+
+    return power_levels
-- 
cgit 1.4.1


From b36095ae5cd88d95802ecf01f8b0f541593ea773 Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <richard@matrix.org>
Date: Tue, 28 Jan 2020 11:08:38 +0000
Subject: Set the PL for aliases events to 0.

---
 synapse/events/utils.py  |  2 +-
 synapse/handlers/room.py | 17 +++++++++++++++--
 2 files changed, 16 insertions(+), 3 deletions(-)

(limited to 'synapse/events/utils.py')

diff --git a/synapse/events/utils.py b/synapse/events/utils.py
index be57c6d9be..f70f5032fb 100644
--- a/synapse/events/utils.py
+++ b/synapse/events/utils.py
@@ -449,7 +449,7 @@ def copy_power_levels_contents(
                 # we should only have one level of nesting
                 if not isinstance(v1, int):
                     raise TypeError(
-                        "Invalid power_levels value for %s.%s: %r" % (k, k1, v)
+                        "Invalid power_levels value for %s.%s: %r" % (k, k1, v1)
                     )
                 h[k1] = v1
             continue
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index 532ee22fa4..a95b45d791 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -287,7 +287,16 @@ class RoomCreationHandler(BaseHandler):
             except AuthError as e:
                 logger.warning("Unable to update PLs in old room: %s", e)
 
-        logger.info("Setting correct PLs in new room to %s", old_room_pl_state.content)
+        new_pl_content = copy_power_levels_contents(old_room_pl_state.content)
+
+        # pre-msc2260 rooms may not have the right setting for aliases. If no other
+        # value is set, set it now.
+        events_default = new_pl_content.get("events_default", 0)
+        new_pl_content.setdefault("events", {}).setdefault(
+            EventTypes.Aliases, events_default
+        )
+
+        logger.info("Setting correct PLs in new room to %s", new_pl_content)
         yield self.event_creation_handler.create_and_send_nonmember_event(
             requester,
             {
@@ -295,7 +304,7 @@ class RoomCreationHandler(BaseHandler):
                 "state_key": "",
                 "room_id": new_room_id,
                 "sender": requester.user.to_string(),
-                "content": old_room_pl_state.content,
+                "content": new_pl_content,
             },
             ratelimit=False,
         )
@@ -812,6 +821,10 @@ class RoomCreationHandler(BaseHandler):
                     EventTypes.RoomHistoryVisibility: 100,
                     EventTypes.CanonicalAlias: 50,
                     EventTypes.RoomAvatar: 50,
+                    # MSC2260: Allow everybody to send alias events by default
+                    # This will be reudundant on pre-MSC2260 rooms, since the
+                    # aliases event is special-cased.
+                    EventTypes.Aliases: 0,
                 },
                 "events_default": 0,
                 "state_default": 50,
-- 
cgit 1.4.1