plugins/muc/history.lib.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2010 Matthew Wild
   3 -- Copyright (C) 2008-2010 Waqas Hussain
   4 -- Copyright (C) 2014 Daurnimator
   5 --
   6 -- This project is MIT/X11 licensed. Please see the
   7 -- COPYING file in the source package for more information.
   8 --
   9
  10 local gettime = os.time;
  11 local datetime = require "util.datetime";
  12 local st = require "util.stanza";
  13
  14 local default_history_length = 20;
  15 local max_history_length = module:get_option_number("max_history_messages", math.huge);
  16
  17 local function set_max_history_length(_max_history_length)
  18         max_history_length = _max_history_length or math.huge;
  19 end
  20
  21 local function get_historylength(room)
  22         return math.min(room._data.history_length or default_history_length, max_history_length);
  23 end
  24
  25 local function set_historylength(room, length)
  26         if length then
  27                 length = assert(tonumber(length), "Length not a valid number");
  28         end
  29         if length == default_history_length then length = nil; end
  30         room._data.history_length = length;
  31         return true;
  32 end
  33
  34 -- Fix for clients who don't support XEP-0045 correctly
  35 -- Default number of history messages the room returns
  36 local function get_defaulthistorymessages(room)
  37         return room._data.default_history_messages or default_history_length;
  38 end
  39 local function set_defaulthistorymessages(room, number)
  40         number = math.min(tonumber(number) or default_history_length, room._data.history_length or default_history_length);
  41         if number == default_history_length then
  42                 number = nil;
  43         end
  44         room._data.default_history_messages = number;
  45 end
  46
  47 module:hook("muc-config-form", function(event)
  48         table.insert(event.form, {
  49                 name = "muc#roomconfig_historylength";
  50                 type = "text-single";
  51                 label = "Maximum number of history messages returned by room";
  52                 desc = "Specify the maximum number of previous messages that should be sent to users when they join the room";
  53                 value = tostring(get_historylength(event.room));
  54         });
  55         table.insert(event.form, {
  56                 name = 'muc#roomconfig_defaulthistorymessages',
  57                 type = 'text-single',
  58                 label = 'Default number of history messages returned by room',
  59                 desc = "Specify the number of previous messages sent to new users when they join the room";
  60                 value = tostring(get_defaulthistorymessages(event.room))
  61         });
  62 end, 70-5);
  63
  64 module:hook("muc-config-submitted/muc#roomconfig_historylength", function(event)
  65         if set_historylength(event.room, event.value) then
  66                 event.status_codes["104"] = true;
  67         end
  68 end);
  69
  70 module:hook("muc-config-submitted/muc#roomconfig_defaulthistorymessages", function(event)
  71         if set_defaulthistorymessages(event.room, event.value) then
  72                 event.status_codes["104"] = true;
  73         end
  74 end);
  75
  76 local function parse_history(stanza)
  77         local x_tag = stanza:get_child("x", "http://jabber.org/protocol/muc");
  78         local history_tag = x_tag and x_tag:get_child("history", "http://jabber.org/protocol/muc");
  79         if not history_tag then
  80                 return nil, nil, nil;
  81         end
  82
  83         local maxchars = tonumber(history_tag.attr.maxchars);
  84
  85         local maxstanzas = tonumber(history_tag.attr.maxstanzas);
  86
  87         -- messages received since the UTC datetime specified
  88         local since = history_tag.attr.since;
  89         if since then
  90                 since = datetime.parse(since);
  91         end
  92
  93         -- messages received in the last "X" seconds.
  94         local seconds = tonumber(history_tag.attr.seconds);
  95         if seconds then
  96                 seconds = gettime() - seconds;
  97                 if since then
  98                         since = math.max(since, seconds);
  99                 else
 100                         since = seconds;
 101                 end
 102         end
 103
 104         return maxchars, maxstanzas, since;
 105 end
 106
 107 module:hook("muc-get-history", function(event)
 108         local room = event.room;
 109         local history = room._history; -- send discussion history
 110         if not history then return nil end
 111         local history_len = #history;
 112
 113         local to = event.to;
 114         local maxchars = event.maxchars;
 115         local maxstanzas = event.maxstanzas or history_len;
 116         local since = event.since;
 117         local n = 0;
 118         local charcount = 0;
 119         for i=history_len,1,-1 do
 120                 local entry = history[i];
 121                 if maxchars then
 122                         if not entry.chars then
 123                                 entry.stanza.attr.to = "";
 124                                 entry.chars = #tostring(entry.stanza);
 125                         end
 126                         charcount = charcount + entry.chars + #to;
 127                         if charcount > maxchars then break; end
 128                 end
 129                 if since and since > entry.timestamp then break; end
 130                 if n + 1 > maxstanzas then break; end
 131                 n = n + 1;
 132         end
 133
 134         local i = history_len-n+1
 135         function event.next_stanza()
 136                 if i > history_len then return nil end
 137                 local entry = history[i];
 138                 local msg = entry.stanza;
 139                 msg.attr.to = to;
 140                 i = i + 1;
 141                 return msg;
 142         end
 143         return true;
 144 end, -1);
 145
 146 local function send_history(room, stanza)
 147         local maxchars, maxstanzas, since = parse_history(stanza);
 148         if not(maxchars or maxstanzas or since) then
 149                 maxstanzas = get_defaulthistorymessages(room);
 150         end
 151         local event = {
 152                 room = room;
 153                 stanza = stanza;
 154                 to = stanza.attr.from; -- `to` is required to calculate the character count for `maxchars`
 155                 maxchars = maxchars,
 156                 maxstanzas = maxstanzas,
 157                 since = since;
 158                 next_stanza = function() end; -- events should define this iterator
 159         };
 160         module:fire_event("muc-get-history", event);
 161         for msg in event.next_stanza, event do
 162                 room:route_stanza(msg);
 163         end
 164 end
 165
 166 -- Send history on join
 167 module:hook("muc-occupant-session-new", function(event)
 168         send_history(event.room, event.stanza);
 169 end, 50); -- Before subject(20)
 170
 171 -- add to history
 172 module:hook("muc-add-history", function(event)
 173         local room = event.room
 174         local history = room._history;
 175         if not history then history = {}; room._history = history; end
 176         local stanza = st.clone(event.stanza);
 177         stanza.attr.to = "";
 178         local ts = gettime();
 179         local stamp = datetime.datetime(ts);
 180         stanza:tag("delay", { -- XEP-0203
 181                 xmlns = "urn:xmpp:delay", from = module.host, stamp = stamp
 182         }):up();
 183         stanza:tag("x", { -- XEP-0091 (deprecated)
 184                 xmlns = "jabber:x:delay", from = module.host, stamp = datetime.legacy()
 185         }):up();
 186         local entry = { stanza = stanza, timestamp = ts };
 187         table.insert(history, entry);
 188         while #history > get_historylength(room) do table.remove(history, 1) end
 189         return true;
 190 end, -1);
 191
 192 -- Have a single muc-add-history event, so that plugins can mark it
 193 -- as handled without stopping other muc-broadcast-message handlers
 194 module:hook("muc-broadcast-message", function(event)
 195         if module:fire_event("muc-message-is-historic", event) then
 196                 module:fire_event("muc-add-history", event);
 197         end
 198 end);
 199
 200 module:hook("muc-message-is-historic", function (event)
 201         return event.stanza:get_child("body");
 202 end, -1);
 203
 204 return {
 205         set_max_length = set_max_history_length;
 206         parse_history = parse_history;
 207         send = send_history;
 208         get_length = get_historylength;
 209         set_length = set_historylength;
 210 };