Spawning from adding some logcontext debug logs in
https://github.com/element-hq/synapse/pull/18966 and since we're not
logging at the `set_current_context(...)` level (see reasoning there),
this removes some usage of `set_current_context(...)`.
Specifically, `MockClock.call_later(...)` doesn't handle logcontexts
correctly. It uses the calling logcontext as the callback context
(wrong, as the logcontext could finish before the callback finishes) and
it didn't reset back to the sentinel context before handing back to the
reactor. It was like this since it was [introduced 10+ years
ago](38da9884e7).
Instead of fixing the implementation which would just be a copy of our
normal `Clock`, we can just remove `MockClock`
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
You can now configure how much media can be uploaded by a user in a
given time period.
Note the first commit here is a refactor of create/upload content
function
This PR makes a few radical changes to media. This now stores the SHA256
hash of each file stored in the database (excluding thumbnails, more on
that later). If a set of media is quarantined, any additional uploads of
the same file contents or any other files with the same hash will be
quarantined at the same time.
Currently this does NOT:
- De-duplicate media, although a future extension could be to do that.
- Run any background jobs to identify the hashes of older files. This
could also be a future extension, though the value of doing so is
limited to combat the abuse of recent media.
- Hash thumbnails. It's assumed that thumbnails are parented to some
form of media, so you'd likely be wanting to quarantine the media and
the thumbnail at the same time.
During the migration the automated script to update the copyright
headers accidentally got rid of some of the existing copyright lines.
Reinstate them.
