Fixes#19347
This deprecates MSC2697 which has been closed since May 2024. As per
#19347 this seems to be a thing we can just rip out. The crypto team
have moved onto MSC3814 and are suggesting that developers who rely on
MSC2697 should use MSC3814 instead.
MSC2697 implementation originally introduced by https://github.com/matrix-org/synapse/pull/8380
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
This is an implementation of MSC4190, which allows appservices to manage
their user's devices without /login & /logout.
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Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>
During the migration the automated script to update the copyright
headers accidentally got rid of some of the existing copyright lines.
Reinstate them.
