util/broadcast.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2010 Matthew Wild
   3 -- Copyright (C) 2008-2010 Waqas Hussain
   4 --
   5 -- This project is MIT/X11 licensed. Please see the
   6 -- COPYING file in the source package for more information.
   7 --
   8
   9
  10 local ipairs, pairs, setmetatable, type =
  11       ipairs, pairs, setmetatable, type;
  12
  13 module "pubsub"
  14
  15 local pubsub_node_mt = { __index = _M };
  16
  17 function new_node(name)
  18         return setmetatable({ name = name, subscribers = {} }, pubsub_node_mt);
  19 end
  20
  21 function set_subscribers(node, subscribers_list, list_type)
  22         local subscribers = node.subscribers;
  23
  24         if list_type == "array" then
  25                 for _, jid in ipairs(subscribers_list) do
  26                         if not subscribers[jid] then
  27                                 node:add_subscriber(jid);
  28                         end
  29                 end
  30         elseif (not list_type) or list_type == "set" then
  31                 for jid in pairs(subscribers_list) do
  32                         if type(jid) == "string" then
  33                                 node:add_subscriber(jid);
  34                         end
  35                 end
  36         end
  37 end
  38
  39 function get_subscribers(node)
  40         return node.subscribers;
  41 end
  42
  43 function publish(node, item, dispatcher, data)
  44         local subscribers = node.subscribers;
  45         for i = 1,#subscribers do
  46                 item.attr.to = subscribers[i];
  47                 dispatcher(data, item);
  48         end
  49 end
  50
  51 function add_subscriber(node, jid)
  52         local subscribers = node.subscribers;
  53         if not subscribers[jid] then
  54                 local space = #subscribers;
  55                 subscribers[space] = jid;
  56                 subscribers[jid] = space;
  57         end
  58 end
  59
  60 function remove_subscriber(node, jid)
  61         local subscribers = node.subscribers;
  62         if subscribers[jid] then
  63                 subscribers[subscribers[jid]] = nil;
  64                 subscribers[jid] = nil;
  65         end
  66 end
  67
  68 return _M;