Implement MSC2414: Make reason and score parameters optional for reporting content

[anoadragon453]

MSC2414 made the reason and score parameters for the POST /_matrix/client/r0/rooms/{roomId}/report/{eventId} endpoint.

That endpoint is implemented in Synapse here:

synapse/synapse/rest/client/v2_alpha/report_event.py

Lines 31 to 46 in 8a4a418

	class ReportEventRestServlet(RestServlet):
	PATTERNS = client_patterns("/rooms/(?P<room_id>[^/]*)/report/(?P<event_id>[^/]*)$")
	def __init__(self, hs):
	super().__init__()
	self.hs = hs
	self.auth = hs.get_auth()
	self.clock = hs.get_clock()
	self.store = hs.get_datastore()
	async def on_POST(self, request, room_id, event_id):
	requester = await self.auth.get_user_by_req(request)
	user_id = requester.user.to_string()
	body = parse_json_object_from_request(request)
	assert_params_in_dict(body, ("reason", "score"))

The Event Reports Admin API should also be updated to state that the reason and content fields may be both blank and null, and the Admin API endpoint should be updated to expect None values for these keys as well:

synapse/synapse/storage/databases/main/room.py

Lines 1388 to 1389 in cbabb31

	er.reason,
	er.content,

(that function may not actually need updating, but it would be good to check that the API still behaves as expected).

Some tests for clients sending reports without reason and score would be great as well.

This will need to be implemented in order to eventually advertise support for the next Client-Server API version.

[clokep]

Should this be optional for all "versions" of the endpoint or only if accessed via /vNext/rooms/....? Not sure how we usually do that?

[anoadragon453]

@clokep The MSC states that it is a change to the existing endpoint (however clients should check whether CS versions the homeserver advertises before potentially omitting a parameter).

As long as we don't advertise support for $next_cs_version before making this change, all should be fine.

[lukasdenk]

@anoadragon453 Is this issue still relevant? Or should it be closed?