This should hopefully speed up `get_auth_chain_difference` a bit in the case of repeated state res on the same rooms.

`get_auth_chain_difference` does a breadth first walk of the auth graphs by repeatedly looking up events' auth events. Different state resolutions on the same room will end up doing a lot of the same event to auth events lookups, so by caching them we should speed things up in cases of repeated state resolutions on the same room.

`adbapi.ConnectionPool` let's you turn on auto reconnect of DB connections. This is off by default.
As far as I can tell if its not enabled dead connections never get removed from the pool.

Maybe helps #8574

Fixes #8618

* Check support room has only two users

* Create 8728.bugfix

* Update synapse/server_notices/server_notices_manager.py

Co-authored-by: Erik Johnston <erik@matrix.org>

Co-authored-by: Erik Johnston <erik@matrix.org>

Signed-off-by: Nicolai Søborg <git@xn--sb-lka.org>

If SSO login is used (e.g. SAML) in a multi worker setup, it should be mentioned that currently all SAML logins must run on the same worker, see https://github.com/matrix-org/synapse/issues/7530

Also, if you are using different ports (for example 443 and 8448) in a reverse proxy for client and federation, the path `/_matrix/media` on the client and federation port must point to the listener of the `media_repository` worker, otherwise you'll get a 404 on the federation port for the path `/_matrix/media`, if a remote server is trying to get the media object on federation port, see https://github.com/matrix-org/synapse/issues/8695

This PR adds some documentation that:

* Describes who the audience for the `docs/`, `docs/dev/` and `docs/admin/` directories are, as well as Synapse's wiki page.
* Stresses that we'd like all documentation to be down in markdown.

Fixes:

```
builtins.TypeError: _reload_logging_config() takes 1 positional argument but 2 were given
```

Add `GET /_synapse/admin/v1/statistics/users/media` to get statisics about local media usage by users.
Related to #6094
It is the first API for statistics.
Goal is to avoid/reduce usage of sql queries like [Wiki analyzing Synapse](https://github.com/matrix-org/synapse/wiki/SQL-for-analyzing-Synapse-PostgreSQL-database-stats

)

Signed-off-by: Dirk Klimpel <dirk@klimpel.org>

Add `displayname` to Shared-Secret Registration for admins to `POST /_synapse/admin/v1/register`

I idly noticed that these lists were out of sync with each other, causing us to miss a table in a test case (`local_invites`). Let's consolidate this list instead to prevent this from happening in the future.

Fixes #8550

Fixes #4042

This PR fixes two things:

* Corrects the copy/paste error of telling the client their displayname is wrong when they are submitting an `avatar_url`.
* Returns a `M_INVALID_PARAM` instead of `M_UNKNOWN` for non-str type parameters.

Reported by @t3chguy.

This could be customised to trigger a different kind of notification in the future, but for now it's a normal non-highlight one.

This bumps us closer to current Python without going all the way to 3.9.

Fixes #8674

Signed-off-by: Dan Callahan <danc@element.io>

We do a `SELECT MAX(stream_id) FROM e2e_cross_signing_keys` on startup.

Fix serialisation errors when using third-party event rules.

* Tie together matches_user_in_member_list and get_users_in_room

* changelog

* Remove type to fix mypy

* Add `on_invalidate` to the function signature in the hopes that may make things work well

* Remove **kwargs

* Update 8676.bugfix

We don't always need the full power of a DeferredCache.

Fixes #6755

Missed in #8671.

* Fix unit tests

* Newsfile

* Tie together matches_user_in_member_list and get_users_in_room

* changelog

* Remove type to fix mypy

* Add `on_invalidate` to the function signature in the hopes that may make things work well

* Remove **kwargs

* Update 8676.bugfix

We do it this way round so that only the "owner" can delete the access token (i.e. `/logout/all` by the "owner" also deletes that token, but `/logout/all` by the "target user" doesn't).

A future PR will add an API for creating such a token.

When the target user and authenticated entity are different the `Processed request` log line will be logged with a: `{@admin:server as @bob:server} ...`. I'm not convinced by that format (especially since it adds spaces in there, making it harder to use `cut -d ' '` to chop off the start of log lines). Suggestions welcome.

Cached functions accept an `on_invalidate` function, which we failed to add to the type signature. It's rarely used in the files that we have typed, which is why we haven't noticed it before.

otherwise non-state events get written as `<FrozenEvent ... state_key='None'>`
which is indistinguishable from state events with the actual state_key `None`.

By not dropping the membership lock between invites, we can stop joins from
grabbing the lock when we're half-done and slowing the whole thing down.

This modifies the configuration of structured logging to be usable from
the standard Python logging configuration.

This also separates the formatting of logs from the transport allowing
JSON logs to files or standard logs to sockets.

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.