Add another bash script to the contrib directory. It creates multiple stream writers and also prints out the example configuration for homeserver.yaml.

Signed-off-by: Ville Petteri Huh.

Signed-off-by: Jörg Behrmann <behrmann@physik.fu-berlin.de>

Fix race conditions in the async cache invalidation logic, by separating
the async & local invalidation calls and ensuring any async call i
executed first.

Signed off by Nick @ Beeper (@Fizzadar).

Signed-off-by: Sean Quah <seanq@matrix.org>

Co-authored-by: David Robertson <davidr@element.io>

This reverts commit 5d4028f2.

To close: #10294.

Signed off by Nick @ Beeper.

More prep work for asyncronous caching, also makes all process_replication_rows methods consistent (presence handler already is so).

Signed off by Nick @ Beeper (@Fizzadar)

Fix https://github.com/matrix-org/synapse/issues/13016

## New error code and status

### Before

Previously, we returned a `404` for `/thumbnail` which isn't even in the spec.

```json
{
  "errcode": "M_NOT_FOUND",
  "error": "Not found [b'hs1', b'tefQeZhmVxoiBfuFQUKRzJxc']"
}
```

### After

What does the spec say?

> 400: The request does not make sense to the server, or the server cannot thumbnail the content. For example, the client requested non-integer dimensions or asked for negatively-sized images.
>
> *-- https://spec.matrix.org/v1.1/client-server-api/#get_matrixmediav3thumbnailservernamemediaid*

Now with this PR, we respond with a `400` when we don't have thumbnails to serve and we explain why we might not have any thumbnails.

```json
{
    "errcode": "M_UNKNOWN",
    "error": "Cannot find any thumbnails for the requested media ([b'example.com', b'12345']). This might mean the media is not a supported_media_format=(image/jpeg, image/jpg, image/webp, image/gif, image/png) or that thumbnailing failed for some other reason. (Dynamic thumbnails are disabled on this server.)",
}
```

> Cannot find any thumbnails for the requested media ([b'example.com', b'12345']). This might mean the media is not a supported_media_format=(image/jpeg, image/jpg, image/webp, image/gif, image/png) or that thumbnailing failed for some other reason. (Dynamic thumbnails are disabled on this server.)


---

We still respond with a 404 in many other places. But we can iterate on those later and maybe keep some in some specific places after spec updates/clarification: https://github.com/matrix-org/matrix-spec/issues/1122

We can also iterate on the bugs where Synapse doesn't thumbnail when it should in other issues/PRs.

Instead of manually inserting fake data. This fixes some issues with
having to manually calculate stream orderings and other oddities.

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

`frozendict` 2.3.2 includes a fix for a memory leak in
`frozendict.__hash__`. This likely has no impact outside of the
deprecated `/initialSync` endpoint, which uses `StreamToken`s,
containing `RoomStreamToken`s, containing `frozendict`s, as cache keys.

Signed-off-by: Sean Quah <seanq@matrix.org>

These columns were added back in Synapse 1.52, and have been populated for new
events since then. It's now (beyond) time to back-populate them for existing
events.

There are two fixes here:
1. A long-standing bug where we incorrectly calculated `delta_ids`; and
2. A bug introduced in #13267 where we got current state incorrect.

When building the docker images for complement testing, copy a preinstalled
complement over from a base image, rather than apt installing it. This avoids
network traffic and is much faster.

Some experimental prep work to enable external event caching based on #9379 & #12955. Doesn't actually move the cache at all, just lays the groundwork for async implemented caches.

Signed off by Nick @ Beeper (@Fizzadar)

* Replace `get_new_events_for_appservice` with `get_all_new_events_stream`

The functions were near identical and this brings the AS worker closer
to the way federation senders work which can allow for multiple workers
to handle AS traffic.

* Pull received TS alongside events when processing the stream

This avoids an extra query -per event- when both federation sender
and appservice pusher process events.

There is a corner in `_check_event_auth` (long known as "the weird corner") where, if we get an event with auth_events which don't match those we were expecting, we attempt to resolve the diffence between our state and the remote's with a state resolution.

This isn't specced, and there's general agreement we shouldn't be doing it.

However, it turns out that the faster-joins code was relying on it, so we need to introduce something similar (but rather simpler) for that.

Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>

* Drop support for v1 unbind

Signed-off-by: Jacek Kusnierz <jacek.kusnierz@tum.de>

* Add changelog

Signed-off-by: Jacek Kusnierz <jacek.kusnierz@tum.de>

* Update changelog.d/13240.misc