Blocking invites

To use policy lists for blocking incoming invites, install the synapse-http-antispam module, then configure it with the ID of the management room you want to use plus the antispam API token from the Meowlnir config file:

modules:
  - module: synapse_http_antispam.HTTPAntispam
    config:
      base_url: http://localhost:29339/_meowlnir/antispam/<management room ID>
      authorization: <value of antispam.secret>
      enabled_callbacks:
      - user_may_invite
      - user_may_join_room
      async:
        user_may_join_room: true

The user_may_invite callback is used to block invites from users who are banned on any of the policy lists that the management room is subscribed to.

The user_may_join_room callback is used to track whether non-blocked invites have been accepted. If auto_reject_invites_token is set in the config, Meowlnir will automatically reject pending invites to rooms from banned users. Even if this callback is not enabled, Meowlnir will still check whether the invites are pending to avoid rejecting already-accepted invites.