view mod_muc_bot/mod_muc_bot.lua @ 6398:9c9889ad4302

mod_unsubscriber: Add MUC support This catches XEP-0045 Join stanzas and replies with an error telling the prospective participant that the supposed MUC is gone. The user or their client can then take action to remove any bookmark or at least disable autojoin.
author Kim Alvefur <zash@zash.se>
date Sat, 07 Feb 2026 12:25:52 +0100
parents 205b9d06fe6b
children
line wrap: on
line source

local st = require "util.stanza";
local jid = require "util.jid";

local bots = module:get_option_set("known_bots", {});

module:hook("muc-occupant-groupchat", function(event)
	if event.occupant then return end -- skip messages from actual occupants
	local room = event.room;

	if bots:contains(jid.bare(event.from)) or bots:contains(jid.host(event.from)) then

		local nick = room:get_registered_nick(jid);

		if not nick then
			-- Allow bot to specify its own nick, but we're appending '[bot]' to it.
			-- FIXME HATS!!!
			nick = event.stanza:get_child_text("nick", "http://jabber.org/protocol/nick");
			nick = (nick or jid.bare(event.from)) .. "[bot]";
		end

		local virtual_occupant_jid = jid.prep(room.jid .. "/" .. nick, true);
		if not virtual_occupant_jid then
			module:send(st.error_reply(event.stanza, "modify", "jid-malformed", "Nickname must pass strict validation", room.jid));
			return true;
		end

		local occupant = room:new_occupant(jid.bare(event.from), virtual_occupant_jid);
		local join = st.presence({from = event.from; to = virtual_occupant_jid});
		local dest_x = st.stanza("x", {xmlns = "http://jabber.org/protocol/muc#user"});
		occupant:set_session(event.from, join, true);
		room:save_occupant(occupant);
		room:publicise_occupant_status(occupant, dest_x);
		-- Inject virtual occupant to trick all the other hooks on this event that
		-- this is an actual legitimate participant.
		event.occupant = occupant;

	end
end, 66);

module:hook("muc-occupant-pre-join", function(event)
	local room = event.room;
	local nick = jid.resource(event.occupant.nick);
	if nick:sub(-5, -1) == "[bot]" then
		event.origin.send(st.error_reply(event.stanza, "modify", "policy-violation", "Only known bots may use the [bot] suffix", room.jid));
		return true;
	end
end, 3);

module:hook("muc-occupant-pre-change", function(event)
	local room = event.room;
	local nick = jid.resource(event.dest_occupant.nick);
	if nick:sub(-5, -1) == "[bot]" then
		event.origin.send(st.error_reply(event.stanza, "modify", "policy-violation", "Only known bots may use the [bot] suffix", room.jid));
		return true;
	end
end, 3);

if not module:get_option_boolean("bots_get_messages", true) then
	module:hook("muc-broadcast-message", function (event)
		event.room:broadcast(event.stanza, function (nick, occupant)
			if nick:sub(-5, -1) == "[bot]" or bots:contains(occupant.bare_jid) or bots:contains(jid.host(occupant.bare_jid)) then
				return false;
			else
				return true;
			end
		end);
		return true;
	end, -100);
end

if module:get_option_boolean("ignore_bot_errors", true) then
	module:hook("message/full", function (event)
		local stanza = event.stanza;
		if stanza.attr.type == "error" then
			if bots:contains(jid.bare(stanza.attr.from)) or bots:contains(jid.host(stanza.attr.from)) then
				module:log("debug", "Ignoring error from known bot");
				return true;
			end
		end
	end, 1);
end

assert(string.sub("foo[bot]", -5, -1) == "[bot]", "substring indicies, how do they work?");