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, max_history_length = 20, math.huge;
  15
  16 local function set_max_history_length(_max_history_length)
  17         max_history_length = _max_history_length or math.huge;
  18 end
  19
  20 local function get_historylength(room)
  21         return math.min(room._data.history_length or default_history_length, max_history_length);
  22 end
  23
  24 local function set_historylength(room, length)
  25         length = assert(tonumber(length), "Length not a valid number");
  26         if length == default_history_length then length = nil; end
  27         room._data.history_length = length;
  28         return true;
  29 end
  30
  31 module:hook("muc-config-form", function(event)
  32         table.insert(event.form, {
  33                 name = "muc#roomconfig_historylength";
  34                 type = "text-single";
  35                 label = "Maximum Number of History Messages Returned by Room";
  36                 value = tostring(get_historylength(event.room));
  37         });
  38 end);
  39
  40 module:hook("muc-config-submitted", function(event)
  41         local new = event.fields["muc#roomconfig_historylength"];
  42         if new ~= nil and set_historylength(event.room, new) then
  43                 event.status_codes["104"] = true;
  44         end
  45 end);
  46
  47 local function parse_history(stanza)
  48         local x_tag = stanza:get_child("x", "http://jabber.org/protocol/muc");
  49         local history_tag = x_tag and x_tag:get_child("history", "http://jabber.org/protocol/muc");
  50         if not history_tag then
  51                 return nil, default_history_length, nil;
  52         end
  53
  54         local maxchars = tonumber(history_tag.attr.maxchars);
  55
  56         local maxstanzas = tonumber(history_tag.attr.maxstanzas);
  57
  58         -- messages received since the UTC datetime specified
  59         local since = history_tag.attr.since;
  60         if since then
  61                 since = datetime.parse(since);
  62         end
  63
  64         -- messages received in the last "X" seconds.
  65         local seconds = tonumber(history_tag.attr.seconds);
  66         if seconds then
  67                 seconds = gettime() - seconds;
  68                 if since then
  69                         since = math.max(since, seconds);
  70                 else
  71                         since = seconds;
  72                 end
  73         end
  74
  75         return maxchars, maxstanzas, since;
  76 end
  77
  78 module:hook("muc-get-history", function(event)
  79         local room = event.room;
  80         local history = room._data["history"]; -- send discussion history
  81         if not history then return nil end
  82         local history_len = #history;
  83
  84         local to = event.to;
  85         local maxchars = event.maxchars;
  86         local maxstanzas = event.maxstanzas or history_len;
  87         local since = event.since;
  88         local n = 0;
  89         local charcount = 0;
  90         for i=history_len,1,-1 do
  91                 local entry = history[i];
  92                 if maxchars then
  93                         if not entry.chars then
  94                                 entry.stanza.attr.to = "";
  95                                 entry.chars = #tostring(entry.stanza);
  96                         end
  97                         charcount = charcount + entry.chars + #to;
  98                         if charcount > maxchars then break; end
  99                 end
 100                 if since and since > entry.timestamp then break; end
 101                 if n + 1 > maxstanzas then break; end
 102                 n = n + 1;
 103         end
 104
 105         local i = history_len-n+1
 106         function event:next_stanza()
 107                 if i > history_len then return nil end
 108                 local entry = history[i];
 109                 local msg = entry.stanza;
 110                 msg.attr.to = to;
 111                 i = i + 1;
 112                 return msg;
 113         end
 114         return true;
 115 end);
 116
 117 local function send_history(room, stanza)
 118         local maxchars, maxstanzas, since = parse_history(stanza);
 119         local event = {
 120                 room = room;
 121                 to = stanza.attr.from; -- `to` is required to calculate the character count for `maxchars`
 122                 maxchars = maxchars, maxstanzas = maxstanzas, since = since;
 123                 next_stanza = function() end; -- events should define this iterator
 124         };
 125         module:fire_event("muc-get-history", event);
 126         for msg in event.next_stanza, event do
 127                 room:route_stanza(msg);
 128         end
 129 end
 130
 131 -- Send history on join
 132 module:hook("muc-occupant-joined", function(event)
 133         send_history(event.room, event.stanza);
 134 end, 50); -- Before subject(20)
 135
 136 -- add to history
 137 module:hook("muc-broadcast-message", function(event)
 138         local historic = event.stanza:get_child("body");
 139         if historic then
 140                 local room = event.room
 141                 local history = room._data["history"];
 142                 if not history then history = {}; room._data["history"] = history; end
 143                 local stanza = st.clone(event.stanza);
 144                 stanza.attr.to = "";
 145                 local ts = gettime();
 146                 local stamp = datetime.datetime(ts);
 147                 stanza:tag("delay", {xmlns = "urn:xmpp:delay", from = module.host, stamp = stamp}):up(); -- XEP-0203
 148                 stanza:tag("x", {xmlns = "jabber:x:delay", from = module.host, stamp = datetime.legacy()}):up(); -- XEP-0091 (deprecated)
 149                 local entry = { stanza = stanza, timestamp = ts };
 150                 table.insert(history, entry);
 151                 while #history > get_historylength(room) do table.remove(history, 1) end
 152         end
 153 end);
 154
 155 return {
 156         set_max_length = set_max_history_length;
 157         parse_history = parse_history;
 158         send = send_history;
 159         get_length = get_historylength;
 160         set_length = set_historylength;
 161 };