This makes the serialization of events synchronous (and it no
longer access the database), but we must manually calculate and
provide the bundled aggregations.
Overall this should cause no change in behavior, but is prep work
for other improvements.
Due to updates to MSC2675 this includes a few fixes:
* Include bundled aggregations for /sync.
* Do not include bundled aggregations for /initialSync and /events.
* Do not bundle aggregations for state events.
* Clarifies comments and variable names.
Adds validation to the Client-Server API to ensure that
the potential thread head does not relate to another event
already. This results in not allowing a thread to "fork" into
other threads.
If the target event is unknown for some reason (maybe it isn't
visible to your homeserver), but is the target of other events
it is assumed that the thread can be created from it. Otherwise,
it is rejected as an unknown event.
Resolve and share `state_groups` for all historical events in batch. This also helps for showing the appropriate avatar/displayname in Element and will work whenever `/messages` has one of the historical messages as the first message in the batch.
This does have the flaw where if you just insert a single historical event somewhere, it probably won't resolve the state correctly from `/messages` or `/context` since it will grab a non historical event above or below with resolved state which never included the historical state back then. For the same reasions, this also does not work in Element between the transition from actual messages to historical messages. In the Gitter case, this isn't really a problem since all of the historical messages are in one big lump at the beginning of the room.
For a future iteration, might be good to look at `/messages` and `/context` to additionally add the `state` for any historical messages in that batch.
---
How are the `state_groups` shared? To illustrate the `state_group` sharing, see this example:
**Before** (new `state_group` for every event 😬, very inefficient):
```
# Tests from https://github.com/matrix-org/complement/pull/206
$ COMPLEMENT_ALWAYS_PRINT_SERVER_LOGS=1 COMPLEMENT_DIR=../complement ./scripts-dev/complement.sh TestBackfillingHistory/parallel/should_resolve_member_state_events_for_historical_events
create_new_client_event m.room.member event=$_JXfwUDIWS6xKGG4SmZXjSFrizhARM7QblhATVWWUcA state_group=None
create_new_client_event org.matrix.msc2716.insertion event=$1ZBfmBKEjg94d-vGYymKrVYeghwBOuGJ3wubU1-I9y0 state_group=9
create_new_client_event org.matrix.msc2716.insertion event=$Mq2JvRetTyclPuozRI682SAjYp3GqRuPc8_cH5-ezPY state_group=10
create_new_client_event m.room.message event=$MfmY4rBQkxrIp8jVwVMTJ4PKnxSigpG9E2cn7S0AtTo state_group=11
create_new_client_event m.room.message event=$uYOv6V8wiF7xHwOMt-60d1AoOIbqLgrDLz6ZIQDdWUI state_group=12
create_new_client_event m.room.message event=$PAbkJRMxb0bX4A6av463faiAhxkE3FEObM1xB4D0UG4 state_group=13
create_new_client_event org.matrix.msc2716.batch event=$Oy_S7AWN7rJQe_MYwGPEy6RtbYklrI-tAhmfiLrCaKI state_group=14
```
**After** (all events in batch sharing `state_group=10`) (the base insertion event has `state_group=8` which matches the `prev_event` we're inserting next to):
```
# Tests from https://github.com/matrix-org/complement/pull/206
$ COMPLEMENT_ALWAYS_PRINT_SERVER_LOGS=1 COMPLEMENT_DIR=../complement ./scripts-dev/complement.sh TestBackfillingHistory/parallel/should_resolve_member_state_events_for_historical_events
create_new_client_event m.room.member event=$PWomJ8PwENYEYuVNoG30gqtybuQQSZ55eldBUSs0i0U state_group=None
create_new_client_event org.matrix.msc2716.insertion event=$e_mCU7Eah9ABF6nQU7lu4E1RxIWccNF05AKaTT5m3lw state_group=9
create_new_client_event org.matrix.msc2716.insertion event=$ui7A3_GdXIcJq0C8GpyrF8X7B3DTjMd_WGCjogax7xU state_group=10
create_new_client_event m.room.message event=$EnTIM5rEGVezQJiYl62uFBl6kJ7B-sMxWqe2D_4FX1I state_group=10
create_new_client_event m.room.message event=$LGx5jGONnBPuNhAuZqHeEoXChd9ryVkuTZatGisOPjk state_group=10
create_new_client_event m.room.message event=$wW0zwoN50lbLu1KoKbybVMxLbKUj7GV_olozIc5i3M0 state_group=10
create_new_client_event org.matrix.msc2716.batch event=$5ZB6dtzqFBCEuMRgpkU201Qhx3WtXZGTz_YgldL6JrQ state_group=10
```
The shared ratelimit function was replaced with a dedicated
RequestRatelimiter class (accessible from the HomeServer
object).
Other properties were copied to each sub-class that inherited
from BaseHandler.
==============================
Bugfixes
--------
- Fix a bug introduced in v1.44.0rc1 which caused the experimental [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716) `/batch_send` endpoint to return a 500 error. ([\#10938](https://github.com/matrix-org/synapse/issues/10938))
- Fix a bug introduced in v1.44.0rc1 which prevented sending presence events to application services. ([\#10944](https://github.com/matrix-org/synapse/issues/10944))
Improved Documentation
----------------------
- Minor updates to the installation instructions. ([\#10919](https://github.com/matrix-org/synapse/issues/10919))
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Merge tag 'v1.44.0rc2' into develop
Synapse 1.44.0rc2 (2021-09-30)
==============================
Bugfixes
--------
- Fix a bug introduced in v1.44.0rc1 which caused the experimental [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716) `/batch_send` endpoint to return a 500 error. ([\#10938](https://github.com/matrix-org/synapse/issues/10938))
- Fix a bug introduced in v1.44.0rc1 which prevented sending presence events to application services. ([\#10944](https://github.com/matrix-org/synapse/issues/10944))
Improved Documentation
----------------------
- Minor updates to the installation instructions. ([\#10919](https://github.com/matrix-org/synapse/issues/10919))
Fix event context for outlier causing failures in all of the MSC2716
Complement tests.
The `EventContext.for_outlier` refactor happened in
https://github.com/matrix-org/synapse/pull/10883
and this spot was left out.
Broadly, the existing `event_auth.check` function has two parts:
* a validation section: checks that the event isn't too big, that it has the rught signatures, etc.
This bit is independent of the rest of the state in the room, and so need only be done once
for each event.
* an auth section: ensures that the event is allowed, given the rest of the state in the room.
This gets done multiple times, against various sets of room state, because it forms part of
the state res algorithm.
Currently, this is implemented with `do_sig_check` and `do_size_check` parameters, but I think
that makes everything hard to follow. Instead, we split the function in two and call each part
separately where it is needed.
This avoids the overhead of searching through the various
configuration classes by directly referencing the class that
the attributes are in.
It also improves type hints since mypy can now resolve the
types of the configuration variables.
Adds missing type hints to methods in the synapse.handlers
module and requires all methods to have type hints there.
This also removes the unused construct_auth_difference method
from the FederationHandler.
This is part of my ongoing war against BaseHandler. I've moved kick_guest_users into RoomMemberHandler (since it calls out to that handler anyway), and split maybe_kick_guest_users into the two places it is called.
* Allow room creator to send MSC2716 related events in existing room versions
Discussed at https://github.com/matrix-org/matrix-doc/pull/2716/#discussion_r682474869
Restoring `get_create_event_for_room_txn` from,
44bb3f0cf5
* Add changelog
* Stop people from trying to redact MSC2716 events in unsupported room versions
* Populate rooms.creator column for easy lookup
> From some [out of band discussion](https://matrix.to/#/!UytJQHLQYfvYWsGrGY:jki.re/$p2fKESoFst038x6pOOmsY0C49S2gLKMr0jhNMz_JJz0?via=jki.re&via=matrix.org), my plan is to use `rooms.creator`. But currently, we don't fill in `creator` for remote rooms when a user is invited to a room for example. So we need to add some code to fill in `creator` wherever we add to the `rooms` table. And also add a background update to fill in the rows missing `creator` (we can use the same logic that `get_create_event_for_room_txn` is doing by looking in the state events to get the `creator`).
>
> https://github.com/matrix-org/synapse/pull/10566#issuecomment-901616642
* Remove and switch away from get_create_event_for_room_txn
* Fix no create event being found because no state events persisted yet
* Fix and add tests for rooms creator bg update
* Populate rooms.creator field for easy lookup
Part of https://github.com/matrix-org/synapse/pull/10566
- Fill in creator whenever we insert into the rooms table
- Add background update to backfill any missing creator values
* Add changelog
* Fix usage
* Remove extra delta already included in #10697
* Don't worry about setting creator for invite
* Only iterate over rows missing the creator
See https://github.com/matrix-org/synapse/pull/10697#discussion_r695940898
* Use constant to fetch room creator field
See https://github.com/matrix-org/synapse/pull/10697#discussion_r696803029
* More protection from other random types
See https://github.com/matrix-org/synapse/pull/10697#discussion_r696806853
* Move new background update to end of list
See https://github.com/matrix-org/synapse/pull/10697#discussion_r696814181
* Fix query casing
* Fix ambiguity iterating over cursor instead of list
Fix `psycopg2.ProgrammingError: no results to fetch` error
when tests run with Postgres.
```
SYNAPSE_POSTGRES=1 SYNAPSE_TEST_LOG_LEVEL=INFO python -m twisted.trial tests.storage.databases.main.test_room
```
---
We use `txn.fetchall` because it will return the results as a
list or an empty list when there are no results.
Docs:
> `cursor` objects are iterable, so, instead of calling explicitly fetchone() in a loop, the object itself can be used:
>
> https://www.psycopg.org/docs/cursor.html#cursor-iterable
And I'm guessing iterating over a raw cursor does something weird when there are no results.
---
Test CI failure: https://github.com/matrix-org/synapse/pull/10697/checks?check_run_id=3468916530
```
tests.test_visibility.FilterEventsForServerTestCase.test_large_room
===============================================================================
[FAIL]
Traceback (most recent call last):
File "/home/runner/work/synapse/synapse/tests/storage/databases/main/test_room.py", line 85, in test_background_populate_rooms_creator_column
self.get_success(
File "/home/runner/work/synapse/synapse/tests/unittest.py", line 500, in get_success
return self.successResultOf(d)
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/trial/_synctest.py", line 700, in successResultOf
self.fail(
twisted.trial.unittest.FailTest: Success result expected on <Deferred at 0x7f4022f3eb50 current result: None>, found failure result instead:
Traceback (most recent call last):
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/internet/defer.py", line 701, in errback
self._startRunCallbacks(fail)
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/internet/defer.py", line 764, in _startRunCallbacks
self._runCallbacks()
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/internet/defer.py", line 858, in _runCallbacks
current.result = callback( # type: ignore[misc]
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/internet/defer.py", line 1751, in gotResult
current_context.run(_inlineCallbacks, r, gen, status)
--- <exception caught here> ---
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/internet/defer.py", line 1657, in _inlineCallbacks
result = current_context.run(
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/python/failure.py", line 500, in throwExceptionIntoGenerator
return g.throw(self.type, self.value, self.tb)
File "/home/runner/work/synapse/synapse/synapse/storage/background_updates.py", line 224, in do_next_background_update
await self._do_background_update(desired_duration_ms)
File "/home/runner/work/synapse/synapse/synapse/storage/background_updates.py", line 261, in _do_background_update
items_updated = await update_handler(progress, batch_size)
File "/home/runner/work/synapse/synapse/synapse/storage/databases/main/room.py", line 1399, in _background_populate_rooms_creator_column
end = await self.db_pool.runInteraction(
File "/home/runner/work/synapse/synapse/synapse/storage/database.py", line 686, in runInteraction
result = await self.runWithConnection(
File "/home/runner/work/synapse/synapse/synapse/storage/database.py", line 791, in runWithConnection
return await make_deferred_yieldable(
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/internet/defer.py", line 858, in _runCallbacks
current.result = callback( # type: ignore[misc]
File "/home/runner/work/synapse/synapse/tests/server.py", line 425, in <lambda>
d.addCallback(lambda x: function(*args, **kwargs))
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/enterprise/adbapi.py", line 293, in _runWithConnection
compat.reraise(excValue, excTraceback)
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/python/deprecate.py", line 298, in deprecatedFunction
return function(*args, **kwargs)
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/python/compat.py", line 404, in reraise
raise exception.with_traceback(traceback)
File "/home/runner/work/synapse/synapse/.tox/py/lib/python3.9/site-packages/twisted/enterprise/adbapi.py", line 284, in _runWithConnection
result = func(conn, *args, **kw)
File "/home/runner/work/synapse/synapse/synapse/storage/database.py", line 786, in inner_func
return func(db_conn, *args, **kwargs)
File "/home/runner/work/synapse/synapse/synapse/storage/database.py", line 554, in new_transaction
r = func(cursor, *args, **kwargs)
File "/home/runner/work/synapse/synapse/synapse/storage/databases/main/room.py", line 1375, in _background_populate_rooms_creator_column_txn
for room_id, event_json in txn:
psycopg2.ProgrammingError: no results to fetch
```
* Move code not under the MSC2716 room version underneath an experimental config option
See https://github.com/matrix-org/synapse/pull/10566#issuecomment-906437909
* Add ordering to rooms creator background update
See https://github.com/matrix-org/synapse/pull/10697#discussion_r696815277
* Add comment to better document constant
See https://github.com/matrix-org/synapse/pull/10697#discussion_r699674458
* Use constant field
* Add some tests to characterise the problem
Some failing. Current states:
RoomsMemberListTestCase
test_get_member_list ...
[OK]
test_get_member_list_mixed_memberships ...
[OK]
test_get_member_list_no_permission ...
[OK]
test_get_member_list_no_permission_former_member ...
[OK]
test_get_member_list_no_permission_former_member_with_at_token ...
[FAIL]
test_get_member_list_no_room ...
[OK]
test_get_member_list_no_permission_with_at_token ...
[FAIL]
* Correct the tests
* Check user is/was member before divulging room membership
* Pull out only the 1 membership event we want.
* Update tests/rest/client/v1/test_rooms.py
Co-authored-by: Erik Johnston <erik@matrix.org>
* Fixup tests (following apply review suggestion)
Co-authored-by: Erik Johnston <erik@matrix.org>
* Add base starting insertion point when no chunk ID is provided
This is so we can have the marker event point to this initial
insertion event and be able to traverse the events in the first chunk.
Because modules might send extra state events when processing an event (e.g. matrix-org/synapse-dinsic#100), and in some cases these extra events might get dropped if we don't recalculate the initial event's auth.
Part of #9744
Removes all redundant `# -*- coding: utf-8 -*-` lines from files, as python 3 automatically reads source code as utf-8 now.
`Signed-off-by: Jonathan de Jong <jonathan@automatia.nl>`
`room_invite_state_types` was inconvenient as a configuration setting, because
anyone that ever set it would not receive any new types that were added to the
defaults. Here, we deprecate the old setting, and replace it with a couple of
new settings under `room_prejoin_state`.
Add off-by-default configuration settings to:
- disable putting an invitee's profile info in invite events
- disable profile lookup via federation
Signed-off-by: Andrew Ferrazzutti <fair@miscworks.net>
- Update black version to the latest
- Run black auto formatting over the codebase
- Run autoformatting according to [`docs/code_style.md
`](80d6dc9783/docs/code_style.md)
- Update `code_style.md` docs around installing black to use the correct version
This could arguably replace the existing admin API for `/members`, however that is out of scope of this change.
This sort of endpoint is ideal for moderation use cases as well as other applications, such as needing to retrieve various bits of information about a room to perform a task (like syncing power levels between two places). This endpoint exposes nothing more than an admin would be able to access with a `select *` query on their database.
Not being able to serialise `frozendicts` is fragile, and it's annoying to have
to think about which serialiser you want. There's no real downside to
supporting frozendicts, so let's just have one json encoder.
This is a requirement for [knocking](https://github.com/matrix-org/synapse/pull/6739), and is abstracting some code that was originally used by the invite flow. I'm separating it out into this PR as it's a fairly contained change.
For a bit of context: when you invite a user to a room, you send them [stripped state events](https://matrix.org/docs/spec/server_server/unstable#put-matrix-federation-v2-invite-roomid-eventid) as part of `invite_room_state`. This is so that their client can display useful information such as the room name and avatar. The same requirement applies to knocking, as it would be nice for clients to be able to display a list of rooms you've knocked on - room name and avatar included.
The reason we're sending membership events down as well is in the case that you are invited to a room that does not have an avatar or name set. In that case, the client should use the displayname/avatar of the inviter. That information is located in the inviter's membership event.
This is optional as knocks don't really have any user in the room to link up to. When you knock on a room, your knock is sent by you and inserted into the room. It wouldn't *really* make sense to show the avatar of a random user - plus it'd be a data leak. So I've opted not to send membership events to the client here. The UX on the client for when you knock on a room without a name/avatar is a separate problem.
In essence this is just moving some inline code to a reusable store method.
This PR allows Synapse modules making use of the `ModuleApi` to create and send non-membership events into a room. This can useful to have modules send messages, or change power levels in a room etc. Note that they must send event through a user that's already in the room.
The non-membership event limitation is currently arbitrary, as it's another chunk of work and not necessary at the moment.
There's no need for it to be in the dict as well as the events table. Instead,
we store it in a separate attribute in the EventInternalMetadata object, and
populate that on load.
This means that we can rely on it being correctly populated for any event which
has been persited to the database.
The idea is to remove some of the places we pass around `int`, where it can represent one of two things:
1. the position of an event in the stream; or
2. a token that partitions the stream, used as part of the stream tokens.
The valid operations are then:
1. did a position happen before or after a token;
2. get all events that happened before or after a token; and
3. get all events between two tokens.
(Note that we don't want to allow other operations as we want to change the tokens to be vector clocks rather than simple ints)
This is *not* ready for production yet. Caveats:
1. We should write some tests...
2. The stream token that we use for events can get stalled at the minimum position of all writers. This means that new events may not be processed and e.g. sent down sync streams if a writer isn't writing or is slow.
The idea here is that we pass the `max_stream_id` to everything, and only use the stream ID of the particular event to figure out *when* the max stream position has caught up to the event and we can notify people about it.
This is to maintain the distinction between the position of an item in the stream (i.e. event A has stream ID 513) and a token that can be used to partition the stream (i.e. give me all events after stream ID 352). This distinction becomes important when the tokens are more complicated than a single number, which they will be once we start tracking the position of multiple writers in the tokens.
The valid operations here are:
1. Is a position before or after a token
2. Fetching all events between two tokens
3. Merging multiple tokens to get the "max", i.e. `C = max(A, B)` means that for all positions P where P is before A *or* before B, then P is before C.
Future PR will change the token type to a dedicated type.
`pusher_pool.on_new_notifications` expected a min and max stream ID, however that was not what we were passing in. Instead, let's just pass it the current max stream ID and have it track the last stream ID it got passed.
I believe that it mostly worked as we called the function for every event. However, it would break for events that got persisted out of order, i.e, that were persisted but the max stream ID wasn't incremented as not all preceding events had finished persisting, and push for that event would be delayed until another event got pushed to the effected users.
This is *not* ready for production yet. Caveats:
1. We should write some tests...
2. The stream token that we use for events can get stalled at the minimum position of all writers. This means that new events may not be processed and e.g. sent down sync streams if a writer isn't writing or is slow.
Small cleanup PR.
* Removed the unused `is_guest` argument
* Added a safeguard to a (currently) impossible code path, fixing static checking at the same time.
If we got an error persisting an event, we would try to remove the push actions
asynchronously, which would lead to a 'Re-starting finished log context'
warning.
I don't think there's any need for this to be asynchronous.
Fixes#2181.
The basic premise is that, when we
fail to reject an invite via the remote server, we can generate our own
out-of-band leave event and persist it as an outlier, so that we have something
to send to the client.
While working on https://github.com/matrix-org/synapse/issues/5665 I found myself digging into the `Ratelimiter` class and seeing that it was both:
* Rather undocumented, and
* causing a *lot* of config checks
This PR attempts to refactor and comment the `Ratelimiter` class, as well as encourage config file accesses to only be done at instantiation.
Best to be reviewed commit-by-commit.
The idea here is that if an instance persists an event via the replication HTTP API it can return before we receive that event over replication, which can lead to races where code assumes that persisting an event immediately updates various caches (e.g. current state of the room).
Most of Synapse doesn't hit such races, so we don't do the waiting automagically, instead we do so where necessary to avoid unnecessary delays. We may decide to change our minds here if it turns out there are a lot of subtle races going on.
People probably want to look at this commit by commit.
... and set it everywhere it's called.
while we're here, rename it for consistency with `check_user_in_room` (and to
help check that I haven't missed any instances)
These are easier to work with than the strings and we normally have one around.
This fixes `FederationHander._persist_auth_tree` which was passing a
RoomVersion object into event_auth.check instead of a string.
Implement part [MSC2228](https://github.com/matrix-org/matrix-doc/pull/2228). The parts that differ are:
* the feature is hidden behind a configuration flag (`enable_ephemeral_messages`)
* self-destruction doesn't happen for state events
* only implement support for the `m.self_destruct_after` field (not the `m.self_destruct` one)
* doesn't send synthetic redactions to clients because for this specific case we consider the clients to be able to destroy an event themselves, instead we just censor it (by pruning its JSON) in the database
Purge jobs don't delete the latest event in a room in order to keep the forward extremity and not break the room. On the other hand, get_state_events, when given an at_token argument calls filter_events_for_client to know if the user can see the event that matches that (sync) token. That function uses the retention policies of the events it's given to filter out those that are too old from a client's view.
Some clients, such as Riot, when loading a room, request the list of members for the latest sync token it knows about, and get confused to the point of refusing to send any message if the server tells it that it can't get that information. This can happen very easily with the message retention feature turned on and a room with low activity so that the last event sent becomes too old according to the room's retention policy.
An easy and clean fix for that issue is to discard the room's retention policies when retrieving state.
`None` is not a valid event id, so queuing up a database fetch for it seems
like a silly thing to do.
I considered making `get_event` return `None` if `event_id is None`, but then
its interaction with `allow_none` seemed uninituitive, and strong typing ftw.
Adds new config option `cleanup_extremities_with_dummy_events` which
periodically sends dummy events to rooms with more than 10 extremities.
THIS IS REALLY EXPERIMENTAL.
