mod_blocklist: Drop blocked messages without error, option to restore compliant behavior
From XEP-0191:
> For message stanzas, the server SHOULD return an error, which SHOULD
> be <service-unavailable/>.
Following this may leak to a blocked JID that they have been blocked,
which seems contrary to the goal of pretending to be perpetually
offline.
-- XEP-0307: Unique Room Names for Multi-User Chat
local st = require "util.stanza";
local unique_name = require "util.id".medium;
module:add_feature "http://jabber.org/protocol/muc#unique"
module:hook("iq-get/host/http://jabber.org/protocol/muc#unique:unique", function(event)
local origin, stanza = event.origin, event.stanza;
origin.send(st.reply(stanza)
:tag("unique", {xmlns = "http://jabber.org/protocol/muc#unique"})
:text(unique_name():lower())
);
return true;
end,-1);