Clean mod_caps.erl from DB specific code

src/mod_caps_sql.erl

@@ -0,0 +1,71 @@
+%%%-------------------------------------------------------------------
+%%% @author Evgeny Khramtsov <ekhramtsov@process-one.net>
+%%% @copyright (C) 2016, Evgeny Khramtsov
+%%% @doc
+%%%
+%%% @end
+%%% Created : 13 Apr 2016 by Evgeny Khramtsov <ekhramtsov@process-one.net>
+%%%-------------------------------------------------------------------
+-module(mod_caps_sql).
+-behaviour(mod_caps).
+
+%% API
+-export([init/2, caps_read/2, caps_write/3, export/1]).
+
+-include("mod_caps.hrl").
+
+%%%===================================================================
+%%% API
+%%%===================================================================
+init(_Host, _Opts) ->
+    ok.
+
+caps_read(LServer, {Node, SubNode}) ->
+    SNode = ejabberd_odbc:escape(Node),
+    SSubNode = ejabberd_odbc:escape(SubNode),
+    case ejabberd_odbc:sql_query(
+	   LServer, [<<"select feature from caps_features where ">>,
+		     <<"node='">>, SNode, <<"' and subnode='">>,
+		     SSubNode, <<"';">>]) of
+	{selected, [<<"feature">>], [[H]|_] = Fs} ->
+	    case catch jlib:binary_to_integer(H) of
+		Int when is_integer(Int), Int>=0 ->
+		    {ok, Int};
+		_ ->
+		    {ok, lists:flatten(Fs)}
+	    end;
+	_ ->
+	    error
+    end.
+
+caps_write(LServer, NodePair, Features) ->
+    ejabberd_odbc:sql_transaction(
+      LServer,
+      sql_write_features_t(NodePair, Features)).
+
+export(_Server) ->
+    [{caps_features,
+      fun(_Host, #caps_features{node_pair = NodePair,
+                                features = Features}) ->
+              sql_write_features_t(NodePair, Features);
+         (_Host, _R) ->
+              []
+      end}].
+
+%%%===================================================================
+%%% Internal functions
+%%%===================================================================
+sql_write_features_t({Node, SubNode}, Features) ->
+    SNode = ejabberd_odbc:escape(Node),
+    SSubNode = ejabberd_odbc:escape(SubNode),
+    NewFeatures = if is_integer(Features) ->
+                          [jlib:integer_to_binary(Features)];
+                     true ->
+                          Features
+                  end,
+    [[<<"delete from caps_features where node='">>,
+      SNode, <<"' and subnode='">>, SSubNode, <<"';">>]|
+     [[<<"insert into caps_features(node, subnode, feature) ">>,
+       <<"values ('">>, SNode, <<"', '">>, SSubNode, <<"', '">>,
+       ejabberd_odbc:escape(F), <<"');">>] || F <- NewFeatures]].
+