This is the first tranche of support for room versioning. It includes:
* setting the default room version in the config file
* new room_version param on the createRoom API
* storing the version of newly-created rooms in the m.room.create event
* fishing the version of existing rooms out of the m.room.create event
Make sure that the user has permission to view the requeseted event for
/event/{eventId} and /room/{roomId}/event/{eventId} requests.
Also check that the event is in the given room for
/room/{roomId}/event/{eventId}, for sanity.
When we get a federation request which refers to an event id, make sure that
said event is in the room the caller claims it is in.
(patch supplied by @turt2live)
This code brings the SimpleHttpClient into line with the
MatrixFederationHttpClient by having it raise HttpResponseExceptions when a
request fails (rather than trying to parse for matrix errors and maybe raising
MatrixCodeMessageException).
Then, whenever we were checking for MatrixCodeMessageException and turning them
into SynapseErrors, we now need to check for HttpResponseExceptions and call
to_synapse_error.
* attempt at deduplicating lazy-loaded members
as per the proposal; we can deduplicate redundant lazy-loaded members
which are sent in the same sync sequence. we do this heuristically
rather than requiring the client to somehow tell us which members it
has chosen to cache, by instead caching the last N members sent to
a client, and not sending them again. For now we hardcode N to 100.
Each cache for a given (user,device) tuple is in turn cached for up to
X minutes (to avoid the caches building up). For now we hardcode X to 30.
* add include_redundant_members filter option & make it work
* remove stale todo
* add tests for _get_some_state_from_cache
* incorporate review
It turns out that looping_call does check the deferred returned by its
callback, and (at least in the case of client_ips), we were relying on this,
and I broke it in #3604.
Update run_as_background_process to return the deferred, and make sure we
return it to clock.looping_call.
