Reproducible on a federated homeserver when there is a membership auth event as a floating outlier. Then when we try to backfill one of that persons messages, it has missing membership auth to fetch which caused us to mistakenly replace the `context` for the message with that of the floating membership `outlier` event. Since `outliers` have no `state` or `state_group`, the error bubbles up when we continue down the persisting route: `sqlite3.IntegrityError: NOT NULL constraint failed: event_to_state_groups.state_group`
Call stack:
```
backfill
_auth_and_persist_event
_check_event_auth
_update_auth_events_and_context_for_auth
```
The idea here is to stop people sending things that aren't joins/leaves/knocks through these endpoints: previously you could send anything you liked through them. I wasn't able to find any security holes from doing so, but it doesn't sound like a good thing.
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>`
- 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
Replaces the `federation_ip_range_blacklist` configuration setting with an
`ip_range_blacklist` setting with wider scope. It now applies to:
* Federation
* Identity servers
* Push notifications
* Checking key validitity for third-party invite events
The old `federation_ip_range_blacklist` setting is still honored if present, but
with reduced scope (it only applies to federation and identity servers).
* Consistently use room_id from federation request body
Some federation APIs have a redundant `room_id` path param (see
https://github.com/matrix-org/matrix-doc/issues/2330). We should make sure we
consistently use either the path param or the body param, and the body param is
easier.
* Kill off some references to "context"
Once upon a time, "rooms" were known as "contexts". I think this kills of the
last references to "contexts".
Fixes a bug where rejected events were persisted with the wrong state group.
Also fixes an occasional internal-server-error when receiving events over
federation which are rejected and (possibly because they are
backwards-extremities) have no prev_group.
Fixes#6289.
