Add knocking support (#81)

Implement knocking as defined by https://github.com/matrix-org/matrix-doc/pull/2403

This is the base knocking stuff, taken from https://github.com/matrix-org/synapse/pull/6739
and does not include any public room directory changes.

While knocking hasn't merged yet on mainline due to waiting on getting Complement
into Synapse's CI, the code has been well-tested.

1 files changed, 3 insertions, 1 deletions

diff --git a/docs/sample_config.yaml b/docs/sample_config.yaml

index c84a61e539..4e6945901c 100644
--- a/docs/sample_config.yaml
+++ b/docs/sample_config.yaml
@@ -1565,7 +1565,9 @@ metrics_flags:
 
 ## API Configuration ##
 
-# A list of event types that will be included in the room_invite_state
+# A list of event types from a room that will be given to users when they
+# are invited to a room. This allows clients to display information about the
+# room that they've been invited to, without actually being in the room yet.
 #
 #room_invite_state_types:
 #  - "m.room.join_rules"