File

plugins/muc/subject.lib.lua @ 11245:43b43e7156b8

MUC: Add support for presence probes (fixes #1535) The following patch allows Prosody to respond to `probe` presences and send out the probed occupant's current presence. This is based on line 17.3 in XEP-0045: A MUC service MAY handle presence probes sent to the room JID <room@service> or an occupant JID <room@service/nick> (e.g, these might be sent by an occupant's home server to determine if the room is still online or to synchronize presence information if the user or the user's server has gone offline temporarily or has started sharing presence again, as for instance when Stanza Interception and Filtering Technology (XEP-0273) is used).
author JC Brand <jc@opkode.com>
date Sun, 19 Apr 2020 21:49:45 +0200
parent 11141:a5acd6354845
child 12977:74b9e05af71e
line wrap: on
line source

-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
-- Copyright (C) 2014 Daurnimator
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

local st = require "util.stanza";
local dt = require "util.datetime";

local muc_util = module:require "muc/util";
local valid_roles = muc_util.valid_roles;

local function create_subject_message(from, subject)
	return st.message({from = from; type = "groupchat"})
		:tag("subject"):text(subject or ""):up();
end

local function get_changesubject(room)
	return room._data.changesubject;
end

local function set_changesubject(room, changesubject)
	changesubject = changesubject and true or nil;
	if get_changesubject(room) == changesubject then return false; end
	room._data.changesubject = changesubject;
	return true;
end

module:hook("muc-disco#info", function (event)
	table.insert(event.form, {
		name = "muc#roomconfig_changesubject";
		type = "boolean";
	});
	event.formdata["muc#roomconfig_changesubject"] = get_changesubject(event.room);
end);

module:hook("muc-config-form", function(event)
	table.insert(event.form, {
		name = "muc#roomconfig_changesubject";
		type = "boolean";
		label = "Allow anyone to set the room's subject";
		desc = "Choose whether anyone, or only moderators, may set the room's subject";
		value = get_changesubject(event.room);
	});
end, 80-1);

module:hook("muc-config-submitted/muc#roomconfig_changesubject", function(event)
	if set_changesubject(event.room, event.value) then
		event.status_codes["104"] = true;
	end
end);

local function get_subject(room)
	-- a <message/> stanza from the room JID (or from the occupant JID of the entity that set the subject)
	return room._data.subject_from or room.jid, room._data.subject;
end

local function send_subject(room, to, time)
	local msg = create_subject_message(get_subject(room));
	msg.attr.to = to;
	if time then
		msg:tag("delay", {
			xmlns = "urn:xmpp:delay",
			from = room.jid,
			stamp = dt.datetime(time);
		}):up();
	end
	room:route_stanza(msg);
end

local function set_subject(room, from, subject)
	if subject == "" then subject = nil; end
	local old_from, old_subject = get_subject(room);
	if old_subject == subject and old_from == from then return false; end
	room._data.subject_from = from;
	room._data.subject = subject;
	room._data.subject_time = os.time();
	local msg = create_subject_message(from, subject);
	room:broadcast_message(msg);
	return true;
end

-- Send subject to joining user
module:hook("muc-occupant-session-new", function(event)
	send_subject(event.room, event.stanza.attr.from, event.room._data.subject_time);
end, 20);

-- Prosody has made the decision that messages with <subject/> are exclusively subject changes
-- e.g. body will be ignored; even if the subject change was not allowed
module:hook("muc-occupant-groupchat", function(event)
	local stanza = event.stanza;
	local subject = stanza:get_child("subject");
	if subject then
		if stanza:get_child("body") or stanza:get_child("thread") then
			-- Note: A message with a <subject/> and a <body/> or a <subject/> and
			-- a <thread/> is a legitimate message, but it SHALL NOT be interpreted
			-- as a subject change.
			return;
		end
		local room = event.room;
		local occupant = event.occupant;
		-- Role check for subject changes
		local role_rank = valid_roles[occupant and occupant.role or "none"];
		if role_rank >= valid_roles.moderator or
			( role_rank >= valid_roles.participant and get_changesubject(room) ) then -- and participant
			set_subject(room, occupant.nick, subject:get_text());
			room:save();
			return true;
		else
			event.origin.send(st.error_reply(stanza, "auth", "forbidden", "You are not allowed to change the subject"));
			return true;
		end
	end
end, 20);

return {
	get_changesubject = get_changesubject;
	set_changesubject = set_changesubject;
	get = get_subject;
	set = set_subject;
	send = send_subject;
};