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mirror of https://github.com/processone/ejabberd.git synced 2024-12-28 17:38:54 +01:00
xmpp.chapril.org-ejabberd/src/mod_mqtt_mnesia.erl
2023-01-10 13:52:04 +01:00

315 lines
9.9 KiB
Erlang

%%%-------------------------------------------------------------------
%%% @author Evgeny Khramtsov <ekhramtsov@process-one.net>
%%% @copyright (C) 2002-2023 ProcessOne, SARL. All Rights Reserved.
%%%
%%% Licensed under the Apache License, Version 2.0 (the "License");
%%% you may not use this file except in compliance with the License.
%%% You may obtain a copy of the License at
%%%
%%% http://www.apache.org/licenses/LICENSE-2.0
%%%
%%% Unless required by applicable law or agreed to in writing, software
%%% distributed under the License is distributed on an "AS IS" BASIS,
%%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%%% See the License for the specific language governing permissions and
%%% limitations under the License.
%%%
%%%-------------------------------------------------------------------
-module(mod_mqtt_mnesia).
-behaviour(mod_mqtt).
%% API
-export([init/2, publish/6, delete_published/2, lookup_published/2]).
-export([list_topics/1, use_cache/1]).
-export([init/0]).
-export([subscribe/4, unsubscribe/2, find_subscriber/2, mqtree_match/1]).
-export([open_session/1, close_session/1, lookup_session/1, get_sessions/2]).
-include("logger.hrl").
-include("mqtt.hrl").
-record(mqtt_pub, {topic_server :: {binary(), binary()},
user :: binary(),
resource :: binary(),
qos :: 0..2,
payload :: binary(),
expiry :: non_neg_integer(),
payload_format = binary :: binary | utf8,
response_topic = <<>> :: binary(),
correlation_data = <<>> :: binary(),
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() | {'_', '_', '$1'},
pid :: pid() | '_',
timestamp :: erlang:timestamp() | '_'}).
%%%===================================================================
%%% API
%%%===================================================================
init(_Host, _Opts) ->
case ejabberd_mnesia:create(
?MODULE, mqtt_pub,
[{disc_only_copies, [node()]},
{attributes, record_info(fields, mqtt_pub)}]) of
{atomic, _} ->
ok;
Err ->
{error, Err}
end.
use_cache(Host) ->
case mnesia:table_info(mqtt_pub, storage_type) of
disc_only_copies ->
mod_mqtt_opt:use_cache(Host);
_ ->
false
end.
publish({U, LServer, R}, Topic, Payload, QoS, Props, ExpiryTime) ->
PayloadFormat = maps:get(payload_format_indicator, Props, binary),
ResponseTopic = maps:get(response_topic, Props, <<"">>),
CorrelationData = maps:get(correlation_data, Props, <<"">>),
ContentType = maps:get(content_type, Props, <<"">>),
UserProps = maps:get(user_property, Props, []),
mnesia:dirty_write(#mqtt_pub{topic_server = {Topic, LServer},
user = U,
resource = R,
qos = QoS,
payload = Payload,
expiry = ExpiryTime,
payload_format = PayloadFormat,
response_topic = ResponseTopic,
correlation_data = CorrelationData,
content_type = ContentType,
user_properties = UserProps}).
delete_published({_, S, _}, Topic) ->
mnesia:dirty_delete(mqtt_pub, {Topic, S}).
lookup_published({_, S, _}, Topic) ->
case mnesia:dirty_read(mqtt_pub, {Topic, S}) of
[#mqtt_pub{qos = QoS,
payload = Payload,
expiry = ExpiryTime,
payload_format = PayloadFormat,
response_topic = ResponseTopic,
correlation_data = CorrelationData,
content_type = ContentType,
user_properties = UserProps}] ->
Props = #{payload_format_indicator => PayloadFormat,
response_topic => ResponseTopic,
correlation_data => CorrelationData,
content_type => ContentType,
user_property => UserProps},
{ok, {Payload, QoS, Props, ExpiryTime}};
[] ->
{error, notfound}
end.
list_topics(S) ->
{ok, [Topic || {Topic, S1} <- mnesia:dirty_all_keys(mqtt_pub), S1 == S]}.
init() ->
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(USR) ->
TS1 = misc: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 ~ts",
Reason, [jid:encode(USR)])
end.
close_session(USR) ->
close_session(USR, self()).
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.
get_sessions(U, S) ->
Resources = mnesia:dirty_select(mqtt_session,
[{#mqtt_session{usr = {U, S, '$1'},
_ = '_'},
[],
['$1']}]),
[{U, S, Resource} || Resource <- Resources].
subscribe({U, S, R} = USR, TopicFilter, SubOpts, ID) ->
T1 = misc: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;
{aborted, Reason} ->
db_fail("Failed to subscribe ~ts to ~ts",
Reason, [jid:encode(USR), TopicFilter])
end.
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 ~ts from ~ts",
Reason, [jid:encode(USR), Topic])
end.
mqtree_match(Topic) ->
Tree = mqtree:whereis(mqtt_sub_index),
mqtree:match(Tree, Topic).
mqtree_multi_match(Topic) ->
{Res, []} = ejabberd_cluster:multicall(?MODULE, mqtree_match, [Topic]),
lists:umerge(Res).
find_subscriber(S, Topic) when is_binary(Topic) ->
case mqtree_multi_match(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 ~ts",
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}.