%%%-------------------------------------------------------------------
%%% @author Evgeny Khramtsov <ekhramtsov@process-one.net>
%%% @copyright (C) 2017, Evgeny Khramtsov
%%% @doc
%%%
%%% @end
%%% Created : 28 Mar 2017 by Evgeny Khramtsov <ekhramtsov@process-one.net>
%%%-------------------------------------------------------------------
-module(mod_bosh_redis).
-behaviour(mod_bosh).
-behaviour(gen_server).
%% API
-export([init/0, open_session/2, close_session/1, find_session/1,
cache_nodes/0]).
%% gen_server callbacks
-export([init/1, handle_cast/2, handle_call/3, handle_info/2,
terminate/2, code_change/3, start_link/0]).
-include("ejabberd.hrl").
-include("logger.hrl").
-include("bosh.hrl").
-record(state, {}).
-define(BOSH_KEY, <<"ejabberd:bosh">>).
%%%===================================================================
%%% API
%%%===================================================================
init() ->
Spec = {?MODULE, {?MODULE, start_link, []},
transient, 5000, worker, [?MODULE]},
case supervisor:start_child(ejabberd_backend_sup, Spec) of
{ok, _Pid} -> ok;
Err -> Err
end.
-spec start_link() -> {ok, pid()} | {error, any()}.
start_link() ->
gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
open_session(SID, Pid) ->
PidBin = term_to_binary(Pid),
case ejabberd_redis:multi(
fun() ->
ejabberd_redis:hset(?BOSH_KEY, SID, PidBin),
ejabberd_redis:publish(?BOSH_KEY, SID)
end) of
{ok, _} ->
ok;
{error, _} ->
{error, db_failure}
end.
close_session(SID) ->
case ejabberd_redis:multi(
fun() ->
ejabberd_redis:hdel(?BOSH_KEY, [SID]),
ejabberd_redis:publish(?BOSH_KEY, SID)
end) of
{ok, _} ->
ok;
{error, _} ->
{error, db_failure}
end.
find_session(SID) ->
case ejabberd_redis:hget(?BOSH_KEY, SID) of
{ok, undefined} ->
{error, notfound};
{ok, Pid} ->
try
{ok, binary_to_term(Pid)}
catch _:badarg ->
?ERROR_MSG("malformed data in redis (key = '~s'): ~p",
[SID, Pid]),
{error, db_failure}
end;
{error, _} ->
{error, db_failure}
end.
cache_nodes() ->
[node()].
%%%===================================================================
%%% gen_server callbacks
%%%===================================================================
init([]) ->
clean_table(),
{ok, #state{}}.
handle_call(_Request, _From, State) ->
Reply = ok,
{reply, Reply, State}.
handle_cast(_Msg, State) ->
{noreply, State}.
handle_info({redis_message, ?BOSH_KEY, SID}, State) ->
ets_cache:delete(?BOSH_CACHE, SID),
{noreply, State};
handle_info(Info, State) ->
?ERROR_MSG("unexpected info: ~p", [Info]),
{noreply, State}.
terminate(_Reason, _State) ->
ok.
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
%%%===================================================================
%%% Internal functions
%%%===================================================================
clean_table() ->
?DEBUG("Cleaning Redis BOSH sessions...", []),
case ejabberd_redis:hgetall(?BOSH_KEY) of
{ok, Vals} ->
ejabberd_redis:multi(
fun() ->
lists:foreach(
fun({SID, Pid}) when node(Pid) == node() ->
ejabberd_redis:hdel(?BOSH_KEY, [SID]);
(_) ->
ok
end, Vals)
end),
ok;
{error, _} ->
?ERROR_MSG("failed to clean bosh sessions in redis", [])
end.
