Previously we were mashing everything together as RoomAccountDataEvent,
even the global events. This technically worked, because of the hidden
custom fields on the ruma event types, but it's confusing and easy to
mess up. Separate methods with appropriate types are preferable.
This became a problem because #foundation-office:matrix.org has a
malformed create event with its `predecessor` set to a string instead of
a map.
The solution to this is, unfortunately, to do more shotgun parsing to
extract only the desired fields rather than trying to parse the entire
content every time. To prevent this kind of problem from happening
again, `RoomCreateEventContent` must only be used for creating new PDUs,
existing PDUs must be shotgun-parsed.
This gets rid of 3 instances of re-parsing the room version.
There's one place where we need the event ID of the room create event to
verify federation responses, so now we just look up the event ID at that
point instead.
Fixes a set of bugs introduced by 00b77144c1,
where we replaced explicit `RoomVersionId` matches with `version < V11`
comparisons. The `Ord` impl on `RoomVersionId` does not work like that,
and is in fact a lexicographic string comparison[1]. The most visible
effect of these bugs is that incoming redaction events would sometimes
be ignored.
Instead of reverting to the explicit matches, which were quite verbose,
I implemented a `RoomVersion` struct that has flags for each property
that we care about. This is similar to the approach used by ruma[2] and
synapse[3].
[1]: 7cfa3be0c6/crates/ruma-common/src/identifiers/room_version_id.rs (L136)
[2]: 7cfa3be0c6/crates/ruma-state-res/src/room_version.rs
[3]: c856ae4724/synapse/api/room_versions.py
It's possible for a server to have multiple associated public keys. This can happen when a Matrix server is set up on a particular domain, its key is lost, and the server continues running on the domain. Now there will be two keys associated to the domain. The old logic wouldn't fetch the new key if we already had the old key cached. The new logic will fetch any keys we don't have that we need, rather than just fetching one key per server.
Previous behavior was causing us to error out of the entire
state_cache::update_membership function when it saw an invalid m.direct,
making it impossible for affected users to join upgraded rooms. This bug
is especially bad if an affected user attempts to upgrade a room,
because we will fail to create their join event in the new room, leaving
both rooms permanently bricked.
The new behavior should never prevent users from joining a room based on
the contents of their account data, and should migrate the `m.direct`
event in a reasonable way even if it is partially corrupted by the
element bug.
This also fixes a bug where the previous implementation will
unintentionally remove any keys that aren't part of the expected
m.direct schema. I don't know of any cases where this came up in
practice.
Fixes: #46