Skip to content

feat: support for room v11 #858

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
FrenchGithubUser wants to merge 2 commits into
base: main
Choose a base branch
from
+35 −10
Open

feat: support for room v11 #858

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
1feb361
feat: support for room v11
FrenchGithubUser Apr 1, 2026
177f831
apply more suggestions
FrenchGithubUser Apr 20, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
23 changes: 14 additions & 9 deletions federation/server_room.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -333,15 +333,20 @@ func InitialRoomEvents(roomVer gomatrixserverlib.RoomVersion, creator string) []
Type: "m.room.create",
StateKey: b.Ptr(""),
Sender: creator,
Content: map[string]interface{}{
"creator": creator,
"room_version": roomVer,
// We have to add randomness to the create event, else if you create 2x v12+ rooms in the same millisecond
// they will get the same room ID, clobbering internal data structures and causing extremely confusing
// behaviour. By adding this entropy, we ensure that even if rooms are created in the same millisecond, their
// hashes will not be the same.
"complement_entropy": util.RandomString(18),
},
Content: func() map[string]interface{} {
content := map[string]interface{}{
"room_version": roomVer,
// We have to add randomness to the create event, else if you create 2x v12+ rooms in the same millisecond
// they will get the same room ID, clobbering internal data structures and causing extremely confusing
// behaviour. By adding this entropy, we ensure that even if rooms are created in the same millisecond, their
// hashes will not be the same.
"complement_entropy": util.RandomString(18),
}
if gomatrixserverlib.MustGetRoomVersion(gomatrixserverlib.RoomVersion(roomVer)).CreatorInCreateEvent() {
Copy link
Copy Markdown
Collaborator

@MadLittleMods MadLittleMods Apr 17, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

TODO: Wait for matrix-org/gomatrixserverlib#465 to merge and update the gomatrixserverlib version in this PR

content["creator"] = creator
}
return content
}(),
},
{
Type: "m.room.member",
Expand Down
7 changes: 6 additions & 1 deletion tests/csapi/rooms_state_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -15,6 +15,7 @@ import (
"github.com/matrix-org/complement/helpers"
"github.com/matrix-org/complement/match"
"github.com/matrix-org/complement/must"
"github.com/matrix-org/gomatrixserverlib"
)

func TestRoomCreationReportsEventsToMyself(t *testing.T) {
Expand All @@ -26,6 +27,7 @@ func TestRoomCreationReportsEventsToMyself(t *testing.T) {
LocalpartSuffix: "bob",
Password: "bobpassword",
})
defaultVer := alice.GetDefaultRoomVersion(t)
roomID := alice.MustCreateRoom(t, map[string]interface{}{})

t.Run("parallel", func(t *testing.T) {
Expand All @@ -38,7 +40,10 @@ func TestRoomCreationReportsEventsToMyself(t *testing.T) {
return false
}
must.Equal(t, ev.Get("sender").Str, alice.UserID, "wrong sender")
must.Equal(t, ev.Get("content").Get("creator").Str, alice.UserID, "wrong content.creator")
// The creator field was removed in room version 11 (MSC4239).
if gomatrixserverlib.MustGetRoomVersion(defaultVer).CreatorInCreateEvent() {
must.Equal(t, ev.Get("content").Get("creator").Str, alice.UserID, "wrong content.creator")
}
Comment on lines +43 to +46
Copy link
Copy Markdown
Collaborator

@MadLittleMods MadLittleMods Apr 17, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Looks like we can use the same CreatorInCreateEvent check in this other spot as well

Copy link
Copy Markdown
Contributor Author

@FrenchGithubUser FrenchGithubUser Apr 20, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

yes indeed, done!

return true
}))
})
Expand Down
15 changes: 15 additions & 0 deletions tests/federation_room_get_missing_events_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -497,6 +497,21 @@ func TestOutboundFederationEventSizeGetMissingEvents(t *testing.T) {
}).Methods("POST")

ver := alice.GetDefaultRoomVersion(t)
// This test crafts a "bad" event which state_key is 280 bytes but only 70
// codepoints.
//
// Room version 11 in Synapse switched from using codepoints to using
// bytes. Which means the 280-byte state_key would be rejected immediately.
// Use room version 10 in that case so the codepoint-based limit is in effect.
//
// Since upgrading a room (for example from v10 to v11) won't carry the event
// (a new room is created), we don't have to worry about v10 room events in a v11
// room.
//
// So this test is essentially skipped for any default room v11 or higher.
if gomatrixserverlib.MustGetRoomVersion(ver).StrictEventByteLimits() {
ver = gomatrixserverlib.RoomVersion("10")
}
Comment on lines 499 to +514
Copy link
Copy Markdown
Collaborator

@MadLittleMods MadLittleMods Apr 17, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This seems like yet another case that we should handle with a new assert iRoomVer.StrictEventByteLimits() check

You can see how we do this in Synapse synapse/event_auth.py#L487-L499

Copy link
Copy Markdown
Contributor Author

@FrenchGithubUser FrenchGithubUser Apr 20, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

yes indeed, done!

Comment on lines 499 to +514
Copy link
Copy Markdown
Collaborator

@MadLittleMods MadLittleMods Apr 17, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Seems like this test would be better if we just always used room version 10 🤔 . The current setup is only better if we're trying to support homeservers that don't support room version 10 yet (do we care about that?)

Suggested change
ver := alice.GetDefaultRoomVersion(t)
// This test crafts a "bad" event which state_key is 280 bytes but only 70
// codepoints.
//
// Room version 11 in Synapse switched from using codepoints to using
// bytes. Which means the 280-byte state_key would be rejected immediately.
// Use room version 10 in that case so the codepoint-based limit is in effect.
//
// Since upgrading a room (for example from v10 to v11) won't carry the event
// (a new room is created), we don't have to worry about v10 room events in a v11
// room.
//
// So this test is essentially skipped for any default room v11 or higher.
verNum, _ := strconv.Atoi(string(ver))
if verNum >= 11 {
ver = gomatrixserverlib.RoomVersion("10")
}
// This test crafts a "bad" event which state_key is 280 bytes but only 70
// codepoints.
//
// Room version 11 in Synapse switched from using codepoints to using
// bytes. Which means the 280-byte state_key would be rejected immediately.
// Use room version 10 in that case so the codepoint-based limit is in effect.
//
// Since upgrading a room (for example from v10 to v11) won't carry the event
// (a new room is created), we don't have to worry about v10 room events in a v11
// room.
//
// So this test is essentially skipped for any default room v11 or higher.
ver = gomatrixserverlib.RoomVersion("10")

Copy link
Copy Markdown
Contributor Author

@FrenchGithubUser FrenchGithubUser Apr 20, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

yea I thought it's better to be flexible (since it's not a big change in the test code), but I can apply your suggestion if you think it's better

Copy link
Copy Markdown
Collaborator

@MadLittleMods MadLittleMods Apr 20, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Probably simplest to converge on room version 10.

If there is a use case for the alternative, we can go that route but the comment should better explain the intention.

charlie := srv.UserID("charlie")
room := srv.MustMakeRoom(t, ver, federation.InitialRoomEvents(ver, charlie))
roomAlias := srv.MakeAliasMapping("flibble", room.RoomID)
Expand Down