Opening on Kegan's behalf
[MSC4284](https://github.com/matrix-org/matrix-spec-proposals/pull/4284)
has already been opened accordingly.
---------
Co-authored-by: Kegan Dougal <7190048+kegsay@users.noreply.github.com>
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
Roughly reviewable commit-by-commit.
This is the first part of adding policy server support to Synapse. Other
parts (unordered), which may or may not be bundled into fewer PRs,
include:
* Implementation of a bulk API
* Supporting a moderation server config (the `fallback_*` options of
https://github.com/element-hq/policyserv_spam_checker )
* Adding an "early event hook" for appservices to receive federation
transactions *before* events are processed formally
* Performance and stability improvements
### 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: turt2live <1190097+turt2live@users.noreply.github.com>
Co-authored-by: Devon Hudson <devon.dmytro@gmail.com>
