Fixes: #19661
Part of: MSC4354
First introduced some helpers for querying a sharded stream, which were moved to
https://github.com/element-hq/synapse/pull/20108.
- SQL builder for 'give me rows between two sharded tokens'
- a function to return the 'new' from_token after a limited read
Then make the sticky events portions of both oldschool and sliding sync use
sharded tokens.
This prevents a 'torn sync' problem where, because the events and sticky
events streams are both sharded with the same writers:
1. persisting a sticky event leads to an event row and a `sticky_events`
row being created for event `e` (on writer `W`).
2. Suppose another writer is still persisting, so the position of the
stream for writer W advances, but the global
['linear'](https://element-hq.github.io/synapse/latest/development/synapse_architecture/streams.html?highlight=%E2%80%9Clinear%E2%80%9D#current-stream-id)
(I have been calling this 'baseline') position does not advance yet.
3. sync is sharding-aware for the regular events stream, so `e` appears
as a real-time timeline event, thus coming down sync
4. since sticky events were not sharding-aware, `e` is not detected as a
sticky event in this sync response. The sticky event position doesn't
advance in the sync token, either.
5. (assume the position advances because other writers have finished
writing and so the 'linear' position advances for the sticky events
stream)
6. the client then syncs again, using the new sync token. This time, `e`
appears in the sticky event section.
If we make sticky events sharding-aware in sync, then `e` would appear
for consideration in both the timeline section **and** the sticky event
section in the first sync.
It then gets deduplicated out of the sticky section since it is
appearing in the timeline section in the same sync.
---------
Signed-off-by: Olivier 'reivilibre <oliverw@matrix.org>
Co-authored-by: Eric Eastwood <erice@element.io>
This pull request fixes a few issues with the profile update stream,
when a user leaves a room. This is basically just mimicking what we
already had for when someone leaves a room, and they no longer share any
rooms, but in reverse - ie when we leave a room, and no longer share
rooms with some users. This was missed in the implementation when adding
the profile update stream for legacy and sliding sync.
[Fix missing profile update stream rows on user leaving
room](https://github.com/element-hq/synapse/commit/e953322226731a99718ebe13139b9c5f05ae4b62)
When a user leaves a room, profile update stream rows are generated with
the `LEFT_ROOM` action for each user in the room that no longer shares a
room with the user who left the room.
This also needs to happen in reverse. The user who left the room needs
to have a profile update stream row for each user they no longer share a
room with.
If we don't do this, clients may keep stale data around even after they
don't share a room with a user, which may mean they don't know when to
refetch profiles after re-joining a room with the stale profile data
user.
[Clear out old profile update stream rows when leaving a
room](https://github.com/element-hq/synapse/commit/e7642bf141b098c1eefaf74655e5e7e18415500b)
When we leave a room, ensure profile update stream rows are cleared out
for every user we no longer share a room with. This is the same as what
happens when someone else leaves a room, but in reverse. The only
remaining profile update stream row should be the `LEFT_ROOM` action.
### Pull Request Checklist
<!-- Please read
https://element-hq.github.io/synapse/latest/development/contributing_guide.html
before submitting your pull request -->
* [x] Pull request is based on the develop branch
* [x] Pull request includes a [changelog
file](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#changelog).
The entry should:
- Be a short description of your change which makes sense to users.
"Fixed a bug that prevented receiving messages from other servers."
instead of "Moved X method from `EventStore` to `EventWorkerStore`.".
- Use markdown where necessary, mostly for `code blocks`.
- End with either a period (.) or an exclamation mark (!).
- Start with a capital letter.
- Feel free to credit yourself, by adding a sentence "Contributed by
@github_username." or "Contributed by [Your Name]." to the end of the
entry.
* [x] [Code
style](https://element-hq.github.io/synapse/latest/code_style.html) is
correct (run the
[linters](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#run-the-linters))
Instead, treat them as absent fields as they feel like they should be.
The database implementation detail that these fields have a dedicated
column with `NULL`
when unset is kept to the storage layer.
The goal here is to reduce the amount of special casing needed for these
two original profile fields and treat them a little bit more like
regular profile fields.
Follows: #20003
Follows: #20147 (needed as a bugfix to continue sending them down
oldschool sync when they get deleted. Without #20147, this PR would
break that — which matches how custom profile fields were broken too.)
---------
Signed-off-by: Olivier 'reivilibre <oliverw@matrix.org>
This PR implements support for profile updates over Sliding Sync:
https://github.com/matrix-org/matrix-spec-proposals/pull/4262. This pr
may be easier to review as a whole than commit by commit.
This builds on the legacy sync profile updates feature
https://github.com/element-hq/synapse/pull/19556, specifically the
profile updates stream it added.
Submitting for early review to get consensus on implementation. There
are some things we would like to add still, from spec, mainly:
* > Homeservers should only consider a profile field update "accepted"
by a client
> once the client returns with a new /sync request with the next /sync
token,
> NOT just after sending down the profile update. The client may never
receive
> response due to network conditions, or a bug in the client
implementation.
* > When a room enters this subset in this connection for the first
time, all requested
> fields from profiles of users in that room MAY be sent down. This
gives the client
> a base set of information for which future field updates can be
applied on top of.
> The homeserver MAY omit some fields and profiles if it believes that
the client has
> already received them, likewise repeat profiles MAY be sent down based
on homeserver
> implementation.
* > Finally, if the list of fields expands to cover a new field ID,
those fields should
> be sent down for all users that are within the current room subset.
Future incremental
> updates will then include changes to this field.
* Additionally, we would need to implement a lazy loading cache similar
to the legacy sync. (not part of MSC as such)
Depending on review these could either be added to this pr, or to keep
this pr from not growing too much, be added in a follow-up pr, as they
are more enhancement to this base sliding sync profile updates
functionality than a part of the core functionality.
### Pull Request Checklist
<!-- Please read
https://element-hq.github.io/synapse/latest/development/contributing_guide.html
before submitting your pull request -->
* [x] Pull request is based on the develop branch
* [x] Pull request includes a [changelog
file](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#changelog).
The entry should:
- Be a short description of your change which makes sense to users.
"Fixed a bug that prevented receiving messages from other servers."
instead of "Moved X method from `EventStore` to `EventWorkerStore`.".
- Use markdown where necessary, mostly for `code blocks`.
- End with either a period (.) or an exclamation mark (!).
- Start with a capital letter.
- Feel free to credit yourself, by adding a sentence "Contributed by
@github_username." or "Contributed by [Your Name]." to the end of the
entry.
* [x] [Code
style](https://element-hq.github.io/synapse/latest/code_style.html) is
correct (run the
[linters](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#run-the-linters))
---------
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Olivier 'reivilibre' <olivier@librepush.net>
Co-authored-by: Olivier 'reivilibre <oliverw@element.io>
Follows: #19487
Part of: MSC4354 whose experimental feature tracking issue is #19409
This PR implements the Sliding Sync (MSC4186) extension described in
MSC4354, allowing sliding sync clients
to receive sticky events in a reliable way.
The logic is much the same as for oldschool sync (implementation in
#19487),
although in the sliding sync extension, the client can choose their own
limit
and must control their own pagination through an extra token in the
extension request/response bodies.
Note this does not yet send down existing sticky events in the
room when the room has been newly-joined.
This newly-discovered gap is tracked at #19662 and will be addressed for
both current sync and MSC4186 SSS soon.
---------
Signed-off-by: Olivier 'reivilibre <oliverw@matrix.org>
Co-authored-by: Eric Eastwood <erice@element.io>
As per the spec, a room with m.room.name value that is absent, null or
empty should be treated as if there is no m.room.name event at all:
https://spec.matrix.org/v1.17/client-server-api/#mroomname
This fetches the full m.room.name event and checks the content.name
instead of only checking the existence of the m.room.name event. This
results in correctly sending heroes for those rooms.
Fixes: https://github.com/element-hq/synapse/issues/19447
Signed-off-by: Joe Groocock <me@frebib.net>
When we port the `Event` class to Rust, the constructor will check for
the existence of required fields. To support that, we tidy up the test
code where we construct fake events to add all the required fields.
There should be no behavioural changes.
Review commit-by-commit.
This fixes the bug described in #19713 (and double-checked against the
SDK integration test, which now passes with this change). A sync
response must be returned immediately if a room subscription
configuration change caused a new non-empty response (checked with `if
response` in the code) to be produced.
Fixes#19713.
Fixes#18844.
---------
Co-authored-by: Erik Johnston <erik@matrix.org>
Follows: #19365
Part of: MSC4354 Sticky Events (experimental feature #19409)
This PR introduces a `spam_checker_spammy` flag, analogous to
`policy_server_spammy`, as an explicit flag
that an event was decided to be spammy by a spam-checker module.
The original Sticky Events PR (#18968) just reused
`policy_server_spammy`, but it didn't sit right with me
because we (at least appear to be experimenting with features that)
allow users to opt-in to seeing
`policy_server_spammy` events (presumably for moderation purposes).
Keeping these flags separate felt best, therefore.
As for why we need this flag: soon soft-failed status won't be
permanent, at least for sticky events.
The spam checker modules currently work by making events soft-failed.
We want to prevent spammy events from getting
reconsidered/un-soft-failed, so it seems like we need
a flag to track spam-checker spamminess *separately* from soft-failed.
Should be commit-by-commit friendly, but is also small.
---------
Signed-off-by: Olivier 'reivilibre <oliverw@matrix.org>
Fixes https://github.com/element-hq/synapse/issues/19175
This PR moves tracking of what lazy loaded membership we've sent to each
room out of the required state table. This avoids that table from
continuously growing, which massively helps performance as we pull out
all matching rows for the connection when we receive a request.
The new table is only read when we have data in a room to send, so we
end up reading a lot fewer rows from the DB. Though we now read from
that table for every room we have events to return in, rather than once
at the start of the request.
For an explanation of how the new table works, see the
[comment](https://github.com/element-hq/synapse/blob/erikj/sss_better_membership_storage2/synapse/storage/schema/main/delta/93/02_sliding_sync_members.sql#L15-L38)
on the table schema.
The table is designed so that we can later prune old entries if we wish,
but that is not implemented in this PR.
Reviewable commit-by-commit.
---------
Co-authored-by: Eric Eastwood <erice@element.io>
We have various constants to try and avoid mistyping of durations, e.g.
`ONE_HOUR_SECONDS * MILLISECONDS_PER_SECOND`, however this can get a
little verbose and doesn't help with typing.
Instead, let's move towards a dedicated `Duration` class (basically a
[`timedelta`](https://docs.python.org/3/library/datetime.html#timedelta-objects)
with helper methods).
This PR introduces the new types and converts all usages of the existing
constants with it. Future PRs may work to move the clock methods to also
use it (e.g. `call_later` and `looping_call`).
Reviewable commit-by-commit.
We add some logic to expire sliding sync connections if they get old or
if there is too much pending data to return.
The values of the constants are picked fairly arbitrarily, these are
currently:
1. More than 100 rooms with pending events if the connection hasn't been
used in over an hour
2. The connection hasn't been used for over a week
Reviewable commit-by-commit
---------
Co-authored-by: Eric Eastwood <erice@element.io>
Introduce `Clock.call_when_running(...)` to wrap startup code in a
logcontext, ensuring we can identify which server generated the logs.
Background:
> Ideally, nothing from the Synapse homeserver would be logged against the `sentinel`
> logcontext as we want to know which server the logs came from. In practice, this is not
> always the case yet especially outside of request handling.
>
> Global things outside of Synapse (e.g. Twisted reactor code) should run in the
> `sentinel` logcontext. It's only when it calls into application code that a logcontext
> gets activated. This means the reactor should be started in the `sentinel` logcontext,
> and any time an awaitable yields control back to the reactor, it should reset the
> logcontext to be the `sentinel` logcontext. This is important to avoid leaking the
> current logcontext to the reactor (which would then get picked up and associated with
> the next thing the reactor does).
>
> *-- `docs/log_contexts.md`
Also adds a lint to prefer `Clock.call_when_running(...)` over
`reactor.callWhenRunning(...)`
Part of https://github.com/element-hq/synapse/issues/18905
This was correctly handled for the "fallback" case where the background
updates hadn't finished
---------
Co-authored-by: Eric Eastwood <erice@element.io>
This is particularly a problem in a state reset scenario where the membership
might change without a corresponding event.
This PR is targeting a scenario where a state reset happens which causes
room membership to change. Previously, the cache would just hold onto
stale data and now we properly bust the cache in this scenario.
We have a few tests for these scenarios which you can see are now fixed
because we can remove the `FIXME` where we were previously manually
busting the cache in the test itself.
This is a general Synapse thing so by it's nature it helps out Sliding
Sync.
Fix https://github.com/element-hq/synapse/issues/17368
Prerequisite for https://github.com/element-hq/synapse/issues/17929
---
Match when are busting `_curr_state_delta_stream_cache`
Reset `sliding_sync_membership_snapshots` -> `forgotten` status when
membership changes (like rejoining a room).
Fix https://github.com/element-hq/synapse/issues/17781
### What was the problem before?
Previously, if someone used `/forget` on one of their rooms, it would
update `sliding_sync_membership_snapshots` as expected but when someone
rejoined the room (or had any membership change), the upsert didn't
overwrite and reset the `forgotten` status so it remained `forgotten`
and invisible down the Sliding Sync endpoint.
Fixes https://github.com/element-hq/synapse/issues/17698
This handles `required_state` changes by checking if new state has been
added to the config, and if so fetching and returning that from the
current state.
This also takes care to ensure that given a state entry S that is added,
removed and then re-added that we do *not* send S down a second time if
there have been no changes to S in the current state. This is fine for
Rust SDK (as it just remembers all state), but we might decide not to do
this behaviour in the MSC. If we decide to always send down S then its
easy enough to rip out all the code.
---------
Co-authored-by: Eric Eastwood <eric.eastwood@beta.gouv.fr>
This is basically exactly the same logic as for receipts. Essentially we
just need to track which room account data we have and haven't sent down
to clients, and use that when we pull stuff out.
I think this just needs a couple of extra tests written
---------
Co-authored-by: Eric Eastwood <eric.eastwood@beta.gouv.fr>
Performance optimization: We can avoid fetching rooms that the user has
left themselves (which could be a significant amount), then only add
back rooms that the user has `newly_left` (left in the token range of an
incremental sync). It's a lot faster to fetch less rooms than fetch them
all and throw them away in most cases. Since the user only leaves a room
(or is state reset out) once in a blue moon, we can avoid a lot of work.
Based on @erikjohnston's branch, erikj/ss_perf
---------
Co-authored-by: Erik Johnston <erik@matrix.org>
No need to sort if the range is large enough to cover all of the rooms
in the list. Previously, we would only do this optimization if the range
was exactly large enough.
Follow-up to https://github.com/element-hq/synapse/pull/17672
This appears to be enough to make Element Web work (or at least move it
on to the next hurdle)
---------
Co-authored-by: Eric Eastwood <eric.eastwood@beta.gouv.fr>
Move filters tests to rest layer in order to test the new (with sliding
sync tables) and fallback paths that Sliding Sync can use.
Also found a bug in the new path because it's not being tested which is
also fixed in this PR. We now take into account `has_known_state` when
filtering.
Spawning from
https://github.com/element-hq/synapse/pull/17662#discussion_r1755574791.
This should have been done when we started using the new sliding sync
tables in https://github.com/element-hq/synapse/pull/17630
We need to bust the `get_sliding_sync_rooms_for_user`
cache when the room encryption is updated and any
other field that is used in the query.
Follow-up to https://github.com/element-hq/synapse/pull/17630
- Bust cache for membership change (cross-reference
`get_rooms_for_user`)
- Bust cache for room `encryption` (cross-reference
`get_room_encryption`)
- Bust cache for `forgotten` (cross-reference
`did_forget`/`get_forgotten_rooms_for_user`)
For rooms with a name we can skip fetching a full room summary, as we
don't need to calculate heroes, and instead just fetch the room counts
directly.
This also changes things to not return counts and heroes for non-joined
rooms. For left/banned rooms we were returning zero values anyway, and
for invite/knock rooms we don't really want to leak such information
(even if some of is included in the stripped state).
Speed up incremental sync by avoiding extra work. We first look at the
state delta changes and only fetch and calculate further derived things
if they have changed.
Olivier 'reivilibre