Support room version 11 (#15912)

And fix a bug in the implementation of the updated redaction
format (MSC2174) where the top-level redacts field was not
properly added for backwards-compatibility.

3 files changed, 20 insertions, 15 deletions

diff --git a/synapse/events/__init__.py b/synapse/events/__init__.py
index 75b62adb33..35257a3b1b 100644
--- a/synapse/events/__init__.py
+++ b/synapse/events/__init__.py
@@ -346,7 +346,7 @@ class EventBase(metaclass=abc.ABCMeta):
     @property
     def redacts(self) -> Optional[str]:
         """MSC2176 moved the redacts field into the content."""
-        if self.room_version.msc2176_redaction_rules:
+        if self.room_version.updated_redaction_rules:
             return self.content.get("redacts")
         return self.get("redacts")
 
diff --git a/synapse/events/builder.py b/synapse/events/builder.py
index a254548c6c..14ea0e6640 100644
--- a/synapse/events/builder.py
+++ b/synapse/events/builder.py
@@ -175,7 +175,7 @@ class EventBuilder:
 
         # MSC2174 moves the redacts property to the content, it is invalid to
         # provide it as a top-level property.
-        if self._redacts is not None and not self.room_version.msc2176_redaction_rules:
+        if self._redacts is not None and not self.room_version.updated_redaction_rules:
             event_dict["redacts"] = self._redacts
 
         if self._origin_server_ts is not None:
diff --git a/synapse/events/utils.py b/synapse/events/utils.py
index a55efcca56..ecfc5c0568 100644
--- a/synapse/events/utils.py
+++ b/synapse/events/utils.py
@@ -108,13 +108,9 @@ def prune_event_dict(room_version: RoomVersion, event_dict: JsonDict) -> JsonDic
         "origin_server_ts",
     ]
 
-    # Room versions from before MSC2176 had additional allowed keys.
-    if not room_version.msc2176_redaction_rules:
-        allowed_keys.extend(["prev_state", "membership"])
-
-    # Room versions before MSC3989 kept the origin field.
-    if not room_version.msc3989_redaction_rules:
-        allowed_keys.append("origin")
+    # Earlier room versions from had additional allowed keys.
+    if not room_version.updated_redaction_rules:
+        allowed_keys.extend(["prev_state", "membership", "origin"])
 
     event_type = event_dict["type"]
 
@@ -127,9 +123,9 @@ def prune_event_dict(room_version: RoomVersion, event_dict: JsonDict) -> JsonDic
 
     if event_type == EventTypes.Member:
         add_fields("membership")
-        if room_version.msc3375_redaction_rules:
+        if room_version.restricted_join_rule_fix:
             add_fields(EventContentFields.AUTHORISING_USER)
-        if room_version.msc3821_redaction_rules:
+        if room_version.updated_redaction_rules:
             # Preserve the signed field under third_party_invite.
             third_party_invite = event_dict["content"].get("third_party_invite")
             if isinstance(third_party_invite, collections.abc.Mapping):
@@ -141,13 +137,13 @@ def prune_event_dict(room_version: RoomVersion, event_dict: JsonDict) -> JsonDic
 
     elif event_type == EventTypes.Create:
         # MSC2176 rules state that create events cannot be redacted.
-        if room_version.msc2176_redaction_rules:
+        if room_version.updated_redaction_rules:
             return event_dict
 
         add_fields("creator")
     elif event_type == EventTypes.JoinRules:
         add_fields("join_rule")
-        if room_version.msc3083_join_rules:
+        if room_version.restricted_join_rule:
             add_fields("allow")
     elif event_type == EventTypes.PowerLevels:
         add_fields(
@@ -161,14 +157,14 @@ def prune_event_dict(room_version: RoomVersion, event_dict: JsonDict) -> JsonDic
             "redact",
         )
 
-        if room_version.msc2176_redaction_rules:
+        if room_version.updated_redaction_rules:
             add_fields("invite")
 
     elif event_type == EventTypes.Aliases and room_version.special_case_aliases_auth:
         add_fields("aliases")
     elif event_type == EventTypes.RoomHistoryVisibility:
         add_fields("history_visibility")
-    elif event_type == EventTypes.Redaction and room_version.msc2176_redaction_rules:
+    elif event_type == EventTypes.Redaction and room_version.updated_redaction_rules:
         add_fields("redacts")
 
     # Protect the rel_type and event_id fields under the m.relates_to field.
@@ -477,6 +473,15 @@ def serialize_event(
     if config.as_client_event:
         d = config.event_format(d)
 
+    # If the event is a redaction, copy the redacts field from the content to
+    # top-level for backwards compatibility.
+    if (
+        e.type == EventTypes.Redaction
+        and e.room_version.updated_redaction_rules
+        and e.redacts is not None
+    ):
+        d["redacts"] = e.redacts
+
     only_event_fields = config.only_event_fields
     if only_event_fields:
         if not isinstance(only_event_fields, list) or not all(