From 30106aaaacf6c2e2c10bcd95963202466a7a1b3b Mon Sep 17 00:00:00 2001 From: Tulir Asokan Date: Mon, 4 Nov 2019 21:14:18 +0200 Subject: [PATCH] Add section about backwards compatibility Signed-off-by: Tulir Asokan --- proposals/2244-mass-redactions.md | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/proposals/2244-mass-redactions.md b/proposals/2244-mass-redactions.md index b2d35dff..4f410356 100644 --- a/proposals/2244-mass-redactions.md +++ b/proposals/2244-mass-redactions.md @@ -17,6 +17,17 @@ It would be easiest to do this before MSC2174 is written into the spec, as then only one migration would be needed: from an event-level redacts string to a content-level redacts array. +### Backwards compatibility +There is no easy way to stay fully compatible with *older* clients, so the +proposed solution is to not support them. In order to not break old clients +completely, servers should still add a `redacts` string containing one of the +redacted event IDs to the top level of `m.room.redaction` events in *newer* +room versions when serving such events over the Client-Server API. + +Like MSC2174, for improved compatibility with *newer* clients, servers should +add a `redacts` array to the `content` of `m.room.redaction` events in *older* +room versions when serving such events over the Client-Server API. + ### Number of redactions Room v4+ event IDs are 44 bytes long, which means the federation event size limit would cap a single redaction event at a bit less than 1500 targets.