Follows: #19365
Part of: MSC4354 Sticky Events (experimental feature #19409)
This PR introduces a `spam_checker_spammy` flag, analogous to
`policy_server_spammy`, as an explicit flag
that an event was decided to be spammy by a spam-checker module.
The original Sticky Events PR (#18968) just reused
`policy_server_spammy`, but it didn't sit right with me
because we (at least appear to be experimenting with features that)
allow users to opt-in to seeing
`policy_server_spammy` events (presumably for moderation purposes).
Keeping these flags separate felt best, therefore.
As for why we need this flag: soon soft-failed status won't be
permanent, at least for sticky events.
The spam checker modules currently work by making events soft-failed.
We want to prevent spammy events from getting
reconsidered/un-soft-failed, so it seems like we need
a flag to track spam-checker spamminess *separately* from soft-failed.
Should be commit-by-commit friendly, but is also small.
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Signed-off-by: Olivier 'reivilibre <oliverw@matrix.org>
Part of: MSC4354 whose experimental feature tracking issue is
https://github.com/element-hq/synapse/issues/19409
Follows: #19340 (a necessary bugfix for `/event/` to set this metadata)
Partially supersedes: #18968
This PR implements the first batch of work to support MSC4354 Sticky
Events.
Sticky events are events that have been configured with a finite
'stickiness' duration,
capped to 1 hour per current MSC draft.
Whilst an event is sticky, we provide stronger delivery guarantees for
the event, both to
our clients and to remote homeservers, essentially making it reliable
delivery as long as we
have a functional connection to the client/server and until the
stickiness expires.
This PR merely supports creating sticky events and receiving the sticky
TTL metadata in clients.
It is not suitable for trialling sticky events since none of the other
semantics are implemented.
Contains a temporary SQLite workaround due to a bug in our supported
version enforcement: https://github.com/element-hq/synapse/issues/19452
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Signed-off-by: Olivier 'reivilibre <oliverw@matrix.org>
Co-authored-by: Eric Eastwood <erice@element.io>
Olivier 'reivilibre