%%%---------------------------------------------------------------------- %%% File : mod_offline.erl %%% Author : Alexey Shchepin %%% Purpose : Store and manage offline messages in Mnesia database. %%% Created : 5 Jan 2003 by Alexey Shchepin %%% Id : $Id$ %%%---------------------------------------------------------------------- -module(mod_offline). -author('alexey@process-one.net'). -behaviour(gen_mod). -export([start/2, init/0, stop/1, store_packet/3, resend_offline_messages/2, pop_offline_messages/3, remove_expired_messages/0, remove_old_messages/1, remove_user/2]). -include("ejabberd.hrl"). -include("jlib.hrl"). -record(offline_msg, {us, timestamp, expire, from, to, packet}). -define(PROCNAME, ejabberd_offline). -define(OFFLINE_TABLE_LOCK_THRESHOLD, 1000). %% TODO: Move this part as a module config file parameter: %% Can be an integer > 0 or infinity: -define(MAX_OFFLINE_MSGS, infinity). start(Host, _Opts) -> mnesia:create_table(offline_msg, [{disc_only_copies, [node()]}, {type, bag}, {attributes, record_info(fields, offline_msg)}]), update_table(), ejabberd_hooks:add(offline_message_hook, Host, ?MODULE, store_packet, 50), ejabberd_hooks:add(resend_offline_messages_hook, Host, ?MODULE, pop_offline_messages, 50), ejabberd_hooks:add(remove_user, Host, ?MODULE, remove_user, 50), ejabberd_hooks:add(anonymous_purge_hook, Host, ?MODULE, remove_user, 50), register(gen_mod:get_module_proc(Host, ?PROCNAME), spawn(?MODULE, init, [])). init() -> loop(). loop() -> receive #offline_msg{us=US} = Msg -> Msgs = receive_all(US, [Msg]), Len = length(Msgs), F = fun() -> Count = Len + p1_mnesia:count_records( offline_msg, #offline_msg{us=US, _='_'}), if Count > ?MAX_OFFLINE_MSGS -> %% TODO: Warn that messages have been discarded ok; true -> if Len >= ?OFFLINE_TABLE_LOCK_THRESHOLD -> mnesia:write_lock_table(offline_msg); true -> ok end, lists:foreach(fun(M) -> mnesia:write(M) end, Msgs) end end, mnesia:transaction(F), loop(); _ -> loop() end. receive_all(US, Msgs) -> receive #offline_msg{us=US} = Msg -> receive_all(US, [Msg | Msgs]) after 0 -> Msgs end. stop(Host) -> ejabberd_hooks:delete(offline_message_hook, Host, ?MODULE, store_packet, 50), ejabberd_hooks:delete(resend_offline_messages_hook, Host, ?MODULE, pop_offline_messages, 50), ejabberd_hooks:delete(remove_user, Host, ?MODULE, remove_user, 50), ejabberd_hooks:delete(anonymous_purge_hook, Host, ?MODULE, remove_user, 50), Proc = gen_mod:get_module_proc(Host, ?PROCNAME), exit(whereis(Proc), stop), {wait, Proc}. store_packet(From, To, Packet) -> Type = xml:get_tag_attr_s("type", Packet), if (Type /= "error") and (Type /= "groupchat") and (Type /= "headline") -> case check_event(From, To, Packet) of true -> #jid{luser = LUser, lserver = LServer} = To, TimeStamp = now(), {xmlelement, _Name, _Attrs, Els} = Packet, Expire = find_x_expire(TimeStamp, Els), gen_mod:get_module_proc(To#jid.lserver, ?PROCNAME) ! #offline_msg{us = {LUser, LServer}, timestamp = TimeStamp, expire = Expire, from = From, to = To, packet = Packet}, stop; _ -> ok end; true -> ok end. check_event(From, To, Packet) -> {xmlelement, Name, Attrs, Els} = Packet, case find_x_event(Els) of false -> true; El -> case xml:get_subtag(El, "id") of false -> case xml:get_subtag(El, "offline") of false -> true; _ -> ID = case xml:get_tag_attr_s("id", Packet) of "" -> {xmlelement, "id", [], []}; S -> {xmlelement, "id", [], [{xmlcdata, S}]} end, ejabberd_router:route( To, From, {xmlelement, Name, Attrs, [{xmlelement, "x", [{"xmlns", ?NS_EVENT}], [ID, {xmlelement, "offline", [], []}]}] }), true end; _ -> false end end. find_x_event([]) -> false; find_x_event([{xmlcdata, _} | Els]) -> find_x_event(Els); find_x_event([El | Els]) -> case xml:get_tag_attr_s("xmlns", El) of ?NS_EVENT -> El; _ -> find_x_event(Els) end. find_x_expire(_, []) -> never; find_x_expire(TimeStamp, [{xmlcdata, _} | Els]) -> find_x_expire(TimeStamp, Els); find_x_expire(TimeStamp, [El | Els]) -> case xml:get_tag_attr_s("xmlns", El) of ?NS_EXPIRE -> Val = xml:get_tag_attr_s("seconds", El), case catch list_to_integer(Val) of {'EXIT', _} -> never; Int when Int > 0 -> {MegaSecs, Secs, MicroSecs} = TimeStamp, S = MegaSecs * 1000000 + Secs + Int, MegaSecs1 = S div 1000000, Secs1 = S rem 1000000, {MegaSecs1, Secs1, MicroSecs}; _ -> never end; _ -> find_x_expire(TimeStamp, Els) end. resend_offline_messages(User, Server) -> LUser = jlib:nodeprep(User), LServer = jlib:nameprep(Server), US = {LUser, LServer}, F = fun() -> Rs = mnesia:wread({offline_msg, US}), mnesia:delete({offline_msg, US}), Rs end, case mnesia:transaction(F) of {atomic, Rs} -> lists:foreach( fun(R) -> {xmlelement, Name, Attrs, Els} = R#offline_msg.packet, ejabberd_sm ! {route, R#offline_msg.from, R#offline_msg.to, {xmlelement, Name, Attrs, Els ++ [jlib:timestamp_to_xml( calendar:now_to_universal_time( R#offline_msg.timestamp))]}} end, lists:keysort(#offline_msg.timestamp, Rs)); _ -> ok end. pop_offline_messages(Ls, User, Server) -> LUser = jlib:nodeprep(User), LServer = jlib:nameprep(Server), US = {LUser, LServer}, F = fun() -> Rs = mnesia:wread({offline_msg, US}), mnesia:delete({offline_msg, US}), Rs end, case mnesia:transaction(F) of {atomic, Rs} -> TS = now(), Ls ++ lists:map( fun(R) -> {xmlelement, Name, Attrs, Els} = R#offline_msg.packet, {route, R#offline_msg.from, R#offline_msg.to, {xmlelement, Name, Attrs, Els ++ [jlib:timestamp_to_xml( calendar:now_to_universal_time( R#offline_msg.timestamp))]}} end, lists:filter( fun(R) -> case R#offline_msg.expire of never -> true; TimeStamp -> TS < TimeStamp end end, lists:keysort(#offline_msg.timestamp, Rs))); _ -> Ls end. remove_expired_messages() -> TimeStamp = now(), F = fun() -> mnesia:write_lock_table(offline_msg), mnesia:foldl( fun(Rec, _Acc) -> case Rec#offline_msg.expire of never -> ok; TS -> if TS < TimeStamp -> mnesia:delete_object(Rec); true -> ok end end end, ok, offline_msg) end, mnesia:transaction(F). remove_old_messages(Days) -> {MegaSecs, Secs, _MicroSecs} = now(), S = MegaSecs * 1000000 + Secs - 60 * 60 * 24 * Days, MegaSecs1 = S div 1000000, Secs1 = S rem 1000000, TimeStamp = {MegaSecs1, Secs1, 0}, F = fun() -> mnesia:write_lock_table(offline_msg), mnesia:foldl( fun(#offline_msg{timestamp = TS} = Rec, _Acc) when TS < TimeStamp -> mnesia:delete_object(Rec); (_Rec, _Acc) -> ok end, ok, offline_msg) end, mnesia:transaction(F). remove_user(User, Server) -> LUser = jlib:nodeprep(User), LServer = jlib:nameprep(Server), US = {LUser, LServer}, F = fun() -> mnesia:delete({offline_msg, US}) end, mnesia:transaction(F). update_table() -> Fields = record_info(fields, offline_msg), case mnesia:table_info(offline_msg, attributes) of Fields -> ok; [user, timestamp, expire, from, to, packet] -> ?INFO_MSG("Converting offline_msg table from " "{user, timestamp, expire, from, to, packet} format", []), Host = ?MYNAME, {atomic, ok} = mnesia:create_table( mod_offline_tmp_table, [{disc_only_copies, [node()]}, {type, bag}, {local_content, true}, {record_name, offline_msg}, {attributes, record_info(fields, offline_msg)}]), mnesia:transform_table(offline_msg, ignore, Fields), F1 = fun() -> mnesia:write_lock_table(mod_offline_tmp_table), mnesia:foldl( fun(#offline_msg{us = U} = R, _) -> mnesia:dirty_write( mod_offline_tmp_table, R#offline_msg{us = {U, Host}}) end, ok, offline_msg) end, mnesia:transaction(F1), mnesia:clear_table(offline_msg), F2 = fun() -> mnesia:write_lock_table(offline_msg), mnesia:foldl( fun(R, _) -> mnesia:dirty_write(R) end, ok, mod_offline_tmp_table) end, mnesia:transaction(F2), mnesia:delete_table(mod_offline_tmp_table); [user, timestamp, from, to, packet] -> ?INFO_MSG("Converting offline_msg table from " "{user, timestamp, from, to, packet} format", []), Host = ?MYNAME, {atomic, ok} = mnesia:create_table( mod_offline_tmp_table, [{disc_only_copies, [node()]}, {type, bag}, {local_content, true}, {record_name, offline_msg}, {attributes, record_info(fields, offline_msg)}]), mnesia:transform_table( offline_msg, fun({_, U, TS, F, T, P}) -> {xmlelement, _Name, _Attrs, Els} = P, Expire = find_x_expire(TS, Els), #offline_msg{us = U, timestamp = TS, expire = Expire, from = F, to = T, packet = P} end, Fields), F1 = fun() -> mnesia:write_lock_table(mod_offline_tmp_table), mnesia:foldl( fun(#offline_msg{us = U} = R, _) -> mnesia:dirty_write( mod_offline_tmp_table, R#offline_msg{us = {U, Host}}) end, ok, offline_msg) end, mnesia:transaction(F1), mnesia:clear_table(offline_msg), F2 = fun() -> mnesia:write_lock_table(offline_msg), mnesia:foldl( fun(R, _) -> mnesia:dirty_write(R) end, ok, mod_offline_tmp_table) end, mnesia:transaction(F2), mnesia:delete_table(mod_offline_tmp_table); _ -> ?INFO_MSG("Recreating offline_msg table", []), mnesia:transform_table(offline_msg, ignore, Fields) end.