util/pubsub.lua

   1 module("pubsub", package.seeall);
   2
   3 local service = {};
   4 local service_mt = { __index = service };
   5
   6 local default_config = {
   7         broadcaster = function () end;
   8         get_affiliation = function () end;
   9         capabilities = {};
  10 };
  11
  12 function new(config)
  13         config = config or {};
  14         return setmetatable({
  15                 config = setmetatable(config, { __index = default_config });
  16                 affiliations = {};
  17                 nodes = {};
  18         }, service_mt);
  19 end
  20
  21 function service:add_subscription(node, actor, jid)
  22         local node_obj = self.nodes[node];
  23         if not node_obj then
  24                 return false, "item-not-found";
  25         end
  26         node_obj.subscribers[jid] = true;
  27         return true;
  28 end
  29
  30 function service:remove_subscription(node, actor, jid)
  31         local node_obj = self.nodes[node];
  32         if not node_obj then
  33                 return false, "item-not-found";
  34         end
  35         if not node_obj.subscribers[jid] then
  36                 return false, "not-subscribed";
  37         end
  38         node_obj.subscribers[jid] = nil;
  39         return true;
  40 end
  41
  42 function service:get_subscription(node, actor, jid)
  43         local node_obj = self.nodes[node];
  44         if node_obj then
  45                 return node_obj.subscribers[jid];
  46         end
  47 end
  48
  49 function service:create(node, actor)
  50         if not self.nodes[node] then
  51                 self.nodes[node] = { name = node, subscribers = {}, config = {}, data = {} };
  52                 return true;
  53         end
  54         return false, "conflict";
  55 end
  56
  57 function service:publish(node, actor, id, item)
  58         local node_obj = self.nodes[node];
  59         if not node_obj then
  60                 node_obj = { name = node, subscribers = {}, config = {}, data = {} };
  61                 self.nodes[node] = node_obj;
  62         end
  63         node_obj.data[id] = item;
  64         self.cb.broadcaster(node, node_obj.subscribers, item);
  65         return true;
  66 end
  67
  68 function service:retract(node, actor, id, retract)
  69         local node_obj = self.nodes[node];
  70         if (not node_obj) or (not node_obj.data[id]) then
  71                 return false, "item-not-found";
  72         end
  73         node_obj.data[id] = nil;
  74         if retract then
  75                 self.cb.broadcaster(node, node_obj.subscribers, retract);
  76         end
  77         return true
  78 end
  79
  80 function service:get(node, actor, id)
  81         local node_obj = self.nodes[node];
  82         if node_obj then
  83                 if id then
  84                         return { node_obj.data[id] };
  85                 else
  86                         return node_obj.data;
  87                 end
  88         end
  89 end
  90
  91 function service:get_nodes(actor)
  92         return true, self.nodes;
  93 end
  94
  95 return _M;