Update mod_mqtt_mnesia.erl

This commit is contained in:
Evgeny Khramtsov 2019-02-26 13:45:53 +03:00
parent daf9c99728
commit 0250826cf9
1 changed files with 181 additions and 14 deletions

View File

@ -21,12 +21,12 @@
%% API
-export([init/2, publish/6, delete_published/2, lookup_published/2]).
-export([list_topics/1, use_cache/1]).
%% Unsupported backend API
-export([init/0]).
-export([subscribe/4, unsubscribe/2, find_subscriber/2]).
-export([open_session/1, close_session/1, lookup_session/1]).
-include("logger.hrl").
-include("mqtt.hrl").
-record(mqtt_pub, {topic_server :: {binary(), binary()},
user :: binary(),
@ -40,6 +40,16 @@
content_type = <<>> :: binary(),
user_properties = [] :: [{binary(), binary()}]}).
-record(mqtt_sub, {topic :: {binary(), binary(), binary(), binary()},
options :: sub_opts(),
id :: non_neg_integer(),
pid :: pid(),
timestamp :: erlang:timestamp()}).
-record(mqtt_session, {usr :: jid:ljid(),
pid :: pid(),
timestamp :: erlang:timestamp()}).
%%%===================================================================
%%% API
%%%===================================================================
@ -107,26 +117,183 @@ list_topics(S) ->
{ok, [Topic || {Topic, S1} <- mnesia:dirty_all_keys(mqtt_pub), S1 == S]}.
init() ->
erlang:nif_error(unsupported_db).
case mqtree:whereis(mqtt_sub_index) of
undefined ->
T = mqtree:new(),
mqtree:register(mqtt_sub_index, T);
_ ->
ok
end,
try
{atomic, ok} = ejabberd_mnesia:create(
?MODULE,
mqtt_session,
[{ram_copies, [node()]},
{attributes, record_info(fields, mqtt_session)}]),
{atomic, ok} = ejabberd_mnesia:create(
?MODULE,
mqtt_sub,
[{ram_copies, [node()]},
{type, ordered_set},
{attributes, record_info(fields, mqtt_sub)}]),
ok
catch _:{badmatch, Err} ->
{error, Err}
end.
open_session(_) ->
erlang:nif_error(unsupported_db).
open_session(USR) ->
TS1 = p1_time_compat:unique_timestamp(),
P1 = self(),
F = fun() ->
case mnesia:read(mqtt_session, USR) of
[#mqtt_session{pid = P2, timestamp = TS2}] ->
if TS1 >= TS2 ->
mod_mqtt_session:route(P2, {replaced, P1}),
mnesia:write(
#mqtt_session{usr = USR,
pid = P1,
timestamp = TS1});
true ->
case is_process_dead(P2) of
true ->
mnesia:write(
#mqtt_session{usr = USR,
pid = P1,
timestamp = TS1});
false ->
mod_mqtt_session:route(P1, {replaced, P2})
end
end;
[] ->
mnesia:write(
#mqtt_session{usr = USR,
pid = P1,
timestamp = TS1})
end
end,
case mnesia:transaction(F) of
{atomic, _} -> ok;
{aborted, Reason} ->
db_fail("Failed to register MQTT session for ~s",
Reason, [jid:encode(USR)])
end.
close_session(_) ->
erlang:nif_error(unsupported_db).
close_session(USR) ->
close_session(USR, self()).
lookup_session(_) ->
erlang:nif_error(unsupported_db).
lookup_session(USR) ->
case mnesia:dirty_read(mqtt_session, USR) of
[#mqtt_session{pid = Pid}] ->
case is_process_dead(Pid) of
true ->
%% Read-Repair
close_session(USR, Pid),
{error, notfound};
false ->
{ok, Pid}
end;
[] ->
{error, notfound}
end.
subscribe(_, _, _, _) ->
erlang:nif_error(unsupported_db).
subscribe({U, S, R} = USR, TopicFilter, SubOpts, ID) ->
T1 = p1_time_compat:unique_timestamp(),
P1 = self(),
Key = {TopicFilter, S, U, R},
F = fun() ->
case mnesia:read(mqtt_sub, Key) of
[#mqtt_sub{timestamp = T2}] when T1 < T2 ->
ok;
_ ->
Tree = mqtree:whereis(mqtt_sub_index),
mqtree:insert(Tree, TopicFilter),
mnesia:write(
#mqtt_sub{topic = {TopicFilter, S, U, R},
options = SubOpts,
id = ID,
pid = P1,
timestamp = T1})
end
end,
case mnesia:transaction(F) of
{atomic, _} -> ok;
{abored, Reason} ->
db_fail("Failed to subscribe ~s to ~s",
Reason, [jid:encode(USR), TopicFilter])
end.
unsubscribe(_, _) ->
erlang:nif_error(unsupported_db).
unsubscribe({U, S, R} = USR, Topic) ->
Pid = self(),
F = fun() ->
Tree = mqtree:whereis(mqtt_sub_index),
mqtree:delete(Tree, Topic),
case mnesia:read(mqtt_sub, {Topic, S, U, R}) of
[#mqtt_sub{pid = Pid} = Obj] ->
mnesia:delete_object(Obj);
_ ->
ok
end
end,
case mnesia:transaction(F) of
{atomic, _} -> ok;
{aborted, Reason} ->
db_fail("Failed to unsubscribe ~s from ~s",
Reason, [jid:encode(USR), Topic])
end.
find_subscriber(_, _) ->
erlang:nif_error(unsupported_db).
find_subscriber(S, Topic) when is_binary(Topic) ->
Tree = mqtree:whereis(mqtt_sub_index),
case mqtree:match(Tree, Topic) of
[Filter|Filters] ->
find_subscriber(S, {Filters, {Filter, S, '_', '_'}});
[] ->
{error, notfound}
end;
find_subscriber(S, {Filters, {Filter, S, _, _} = Prev}) ->
case mnesia:dirty_next(mqtt_sub, Prev) of
{Filter, S, _, _} = Next ->
case mnesia:dirty_read(mqtt_sub, Next) of
[#mqtt_sub{options = SubOpts, id = ID, pid = Pid}] ->
case is_process_dead(Pid) of
true ->
find_subscriber(S, {Filters, Next});
false ->
{ok, {Pid, SubOpts, ID}, {Filters, Next}}
end;
[] ->
find_subscriber(S, {Filters, Next})
end;
_ ->
case Filters of
[] ->
{error, notfound};
[Filter1|Filters1] ->
find_subscriber(S, {Filters1, {Filter1, S, '_', '_'}})
end
end.
%%%===================================================================
%%% Internal functions
%%%===================================================================
close_session(USR, Pid) ->
F = fun() ->
case mnesia:read(mqtt_session, USR) of
[#mqtt_session{pid = Pid} = Obj] ->
mnesia:delete_object(Obj);
_ ->
ok
end
end,
case mnesia:transaction(F) of
{atomic, _} -> ok;
{aborted, Reason} ->
db_fail("Failed to unregister MQTT session for ~s",
Reason, [jid:encode(USR)])
end.
is_process_dead(Pid) ->
node(Pid) == node() andalso not is_process_alive(Pid).
db_fail(Format, Reason, Args) ->
?ERROR_MSG(Format ++ ": ~p", Args ++ [Reason]),
{error, db_failure}.