util/rsm.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2017 Matthew Wild
   3 -- Copyright (C) 2008-2017 Waqas Hussain
   4 -- Copyright (C) 2011-2017 Kim Alvefur
   5 --
   6 -- This project is MIT/X11 licensed. Please see the
   7 -- COPYING file in the source package for more information.
   8 --
   9 -- XEP-0313: Message Archive Management for Prosody
  10 --
  11
  12 local stanza = require"util.stanza".stanza;
  13 local tostring, tonumber = tostring, tonumber;
  14 local type = type;
  15 local pairs = pairs;
  16
  17 local xmlns_rsm = 'http://jabber.org/protocol/rsm';
  18
  19 local element_parsers = {};
  20
  21 do
  22         local parsers = element_parsers;
  23         local function xs_int(st)
  24                 return tonumber((st:get_text()));
  25         end
  26         local function xs_string(st)
  27                 return st:get_text();
  28         end
  29
  30         parsers.after = xs_string;
  31         parsers.before = function(st)
  32                         local text = st:get_text();
  33                         return text == "" or text;
  34                 end;
  35         parsers.max = xs_int;
  36         parsers.index = xs_int;
  37
  38         parsers.first = function(st)
  39                         return { index = tonumber(st.attr.index); st:get_text() };
  40                 end;
  41         parsers.last = xs_string;
  42         parsers.count = xs_int;
  43 end
  44
  45 local element_generators = setmetatable({
  46         first = function(st, data)
  47                 if type(data) == "table" then
  48                         st:tag("first", { index = data.index }):text(data[1]):up();
  49                 else
  50                         st:tag("first"):text(tostring(data)):up();
  51                 end
  52         end;
  53         before = function(st, data)
  54                 if data == true then
  55                         st:tag("before"):up();
  56                 else
  57                         st:tag("before"):text(tostring(data)):up();
  58                 end
  59         end
  60 }, {
  61         __index = function(_, name)
  62                 return function(st, data)
  63                         st:tag(name):text(tostring(data)):up();
  64                 end
  65         end;
  66 });
  67
  68
  69 local function parse(set)
  70         local rs = {};
  71         for tag in set:childtags() do
  72                 local name = tag.name;
  73                 local parser = name and element_parsers[name];
  74                 if parser then
  75                         rs[name] = parser(tag);
  76                 end
  77         end
  78         return rs;
  79 end
  80
  81 local function generate(t)
  82         local st = stanza("set", { xmlns = xmlns_rsm });
  83         for k,v in pairs(t) do
  84                 if element_parsers[k] then
  85                         element_generators[k](st, v);
  86                 end
  87         end
  88         return st;
  89 end
  90
  91 local function get(st)
  92         local set = st:get_child("set", xmlns_rsm);
  93         if set and #set.tags > 0 then
  94                 return parse(set);
  95         end
  96 end
  97
  98 return { parse = parse, generate = generate, get = get };