emqx/src/emqttd_server.erl

307 lines
11 KiB
Erlang

%%--------------------------------------------------------------------
%% Copyright (c) 2012-2016 Feng Lee <feng@emqtt.io>.
%%
%% 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(emqttd_server).
-author("Feng Lee <feng@emqtt.io>").
-behaviour(gen_server2).
-include("emqttd.hrl").
-include("emqttd_protocol.hrl").
-include("emqttd_internal.hrl").
-export([start_link/3]).
%% PubSub API.
-export([subscribe/1, subscribe/2, subscribe/3, publish/1,
unsubscribe/1, unsubscribe/2]).
%% Async PubSub API.
-export([async_subscribe/1, async_subscribe/2, async_subscribe/3,
async_unsubscribe/1, async_unsubscribe/2]).
%% Management API.
-export([setqos/3, subscriptions/1, subscribers/1, is_subscribed/2,
subscriber_down/1]).
%% Debug API
-export([dump/0]).
%% gen_server.
-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
terminate/2, code_change/3]).
-record(state, {pool, id, env, submon :: emqttd_pmon:pmon()}).
%% @doc Start server
-spec(start_link(atom(), pos_integer(), list()) -> {ok, pid()} | ignore | {error, any()}).
start_link(Pool, Id, Env) ->
gen_server2:start_link({local, ?PROC_NAME(?MODULE, Id)}, ?MODULE, [Pool, Id, Env], []).
%%--------------------------------------------------------------------
%% PubSub API
%%--------------------------------------------------------------------
%% @doc Subscribe a Topic
-spec(subscribe(binary()) -> ok | emqttd:pubsub_error()).
subscribe(Topic) when is_binary(Topic) ->
subscribe(Topic, self()).
-spec(subscribe(binary(), emqttd:subscriber()) -> ok | emqttd:pubsub_error()).
subscribe(Topic, Subscriber) when is_binary(Topic) ->
subscribe(Topic, Subscriber, []).
-spec(subscribe(binary(), emqttd:subscriber(), [emqttd:suboption()]) ->
ok | emqttd:pubsub_error()).
subscribe(Topic, Subscriber, Options) when is_binary(Topic) ->
call(pick(Subscriber), {subscribe, Topic, Subscriber, Options}).
%% @doc Subscribe a Topic Asynchronously
-spec(async_subscribe(binary()) -> ok).
async_subscribe(Topic) when is_binary(Topic) ->
async_subscribe(Topic, self()).
-spec(async_subscribe(binary(), emqttd:subscriber()) -> ok).
async_subscribe(Topic, Subscriber) when is_binary(Topic) ->
async_subscribe(Topic, Subscriber, []).
-spec(async_subscribe(binary(), emqttd:subscriber(), [emqttd:suboption()]) -> ok).
async_subscribe(Topic, Subscriber, Options) when is_binary(Topic) ->
cast(pick(Subscriber), {subscribe, Topic, Subscriber, Options}).
%% @doc Publish message to Topic.
-spec(publish(mqtt_message()) -> {ok, mqtt_delivery()} | ignore).
publish(Msg = #mqtt_message{from = From}) ->
trace(publish, From, Msg),
case emqttd_hook:run('message.publish', [], Msg) of
{ok, Msg1 = #mqtt_message{topic = Topic}} ->
emqttd_pubsub:publish(Topic, Msg1);
{stop, Msg1} ->
lager:warning("Stop publishing: ~s", [emqttd_message:format(Msg1)]),
ignore
end.
trace(publish, From, _Msg) when is_atom(From) ->
%% Dont' trace '$SYS' publish
ignore;
trace(publish, {ClientId, Username}, #mqtt_message{topic = Topic, payload = Payload}) ->
lager:info([{client, ClientId}, {topic, Topic}],
"~s/~s PUBLISH to ~s: ~p", [ClientId, Username, Topic, Payload]);
trace(publish, From, #mqtt_message{topic = Topic, payload = Payload}) when is_binary(From); is_list(From) ->
lager:info([{client, From}, {topic, Topic}],
"~s PUBLISH to ~s: ~p", [From, Topic, Payload]).
%% @doc Unsubscribe
-spec(unsubscribe(binary()) -> ok | emqttd:pubsub_error()).
unsubscribe(Topic) when is_binary(Topic) ->
unsubscribe(Topic, self()).
%% @doc Unsubscribe
-spec(unsubscribe(binary(), emqttd:subscriber()) -> ok | emqttd:pubsub_error()).
unsubscribe(Topic, Subscriber) when is_binary(Topic) ->
call(pick(Subscriber), {unsubscribe, Topic, Subscriber}).
%% @doc Async Unsubscribe
-spec(async_unsubscribe(binary()) -> ok).
async_unsubscribe(Topic) when is_binary(Topic) ->
async_unsubscribe(Topic, self()).
-spec(async_unsubscribe(binary(), emqttd:subscriber()) -> ok).
async_unsubscribe(Topic, Subscriber) when is_binary(Topic) ->
cast(pick(Subscriber), {unsubscribe, Topic, Subscriber}).
setqos(Topic, Subscriber, Qos) when is_binary(Topic) ->
call(pick(Subscriber), {setqos, Topic, Subscriber, Qos}).
-spec(subscriptions(emqttd:subscriber()) -> [{binary(), list(emqttd:suboption())}]).
subscriptions(Subscriber) ->
lists:map(fun({_, {_Share, Topic}}) ->
subscription(Topic, Subscriber);
({_, Topic}) ->
subscription(Topic, Subscriber)
end, ets:lookup(mqtt_subscription, Subscriber)).
subscription(Topic, Subscriber) ->
{Topic, Subscriber, ets:lookup_element(mqtt_subproperty, {Topic, Subscriber}, 2)}.
subscribers(Topic) -> emqttd_pubsub:subscribers(Topic).
-spec(is_subscribed(binary(), emqttd:subscriber()) -> boolean()).
is_subscribed(Topic, Subscriber) when is_binary(Topic) ->
ets:member(mqtt_subproperty, {Topic, Subscriber}).
-spec(subscriber_down(emqttd:subscriber()) -> ok).
subscriber_down(Subscriber) ->
cast(pick(Subscriber), {subscriber_down, Subscriber}).
call(Server, Req) ->
gen_server2:call(Server, Req, infinity).
cast(Server, Msg) when is_pid(Server) ->
gen_server2:cast(Server, Msg).
pick(Subscriber) ->
gproc_pool:pick_worker(server, Subscriber).
dump() ->
[{Tab, ets:tab2list(Tab)} || Tab <- [mqtt_subproperty, mqtt_subscription, mqtt_subscriber]].
%%--------------------------------------------------------------------
%% gen_server Callbacks
%%--------------------------------------------------------------------
init([Pool, Id, Env]) ->
?GPROC_POOL(join, Pool, Id),
{ok, #state{pool = Pool, id = Id, env = Env, submon = emqttd_pmon:new()}}.
handle_call({subscribe, Topic, Subscriber, Options}, _From, State) ->
case do_subscribe_(Topic, Subscriber, Options, State) of
{ok, NewState} -> {reply, ok, setstats(NewState)};
{error, Error} -> {reply, {error, Error}, State}
end;
handle_call({unsubscribe, Topic, Subscriber}, _From, State) ->
case do_unsubscribe_(Topic, Subscriber, State) of
{ok, NewState} -> {reply, ok, setstats(NewState), hibernate};
{error, Error} -> {reply, {error, Error}, State}
end;
handle_call({setqos, Topic, Subscriber, Qos}, _From, State) ->
Key = {Topic, Subscriber},
case ets:lookup(mqtt_subproperty, Key) of
[{_, Opts}] ->
Opts1 = lists:ukeymerge(1, [{qos, Qos}], Opts),
ets:insert(mqtt_subproperty, {Key, Opts1}),
{reply, ok, State};
[] ->
{reply, {error, {subscription_not_found, Topic}}, State}
end;
handle_call(Req, _From, State) ->
?UNEXPECTED_REQ(Req, State).
handle_cast({subscribe, Topic, Subscriber, Options}, State) ->
case do_subscribe_(Topic, Subscriber, Options, State) of
{ok, NewState} -> {noreply, setstats(NewState)};
{error, _Error} -> {noreply, State}
end;
handle_cast({unsubscribe, Topic, Subscriber}, State) ->
case do_unsubscribe_(Topic, Subscriber, State) of
{ok, NewState} -> {noreply, setstats(NewState), hibernate};
{error, _Error} -> {noreply, State}
end;
handle_cast({subscriber_down, Subscriber}, State) ->
subscriber_down_(Subscriber),
{noreply, setstats(State)};
handle_cast(Msg, State) ->
?UNEXPECTED_MSG(Msg, State).
handle_info({'DOWN', _MRef, process, DownPid, _Reason}, State = #state{submon = PM}) ->
subscriber_down_(DownPid),
{noreply, setstats(State#state{submon = PM:erase(DownPid)}), hibernate};
handle_info(Info, State) ->
?UNEXPECTED_INFO(Info, State).
terminate(_Reason, #state{pool = Pool, id = Id}) ->
?GPROC_POOL(leave, Pool, Id).
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
%%--------------------------------------------------------------------
%% Internal Functions
%%--------------------------------------------------------------------
do_subscribe_(Topic, Subscriber, Options, State) ->
case ets:lookup(mqtt_subproperty, {Topic, Subscriber}) of
[] ->
emqttd_pubsub:async_subscribe(Topic, Subscriber, Options),
Share = proplists:get_value(share, Options),
add_subscription_(Share, Subscriber, Topic),
ets:insert(mqtt_subproperty, {{Topic, Subscriber}, Options}),
{ok, monitor_subpid(Subscriber, State)};
[_] ->
{error, {already_subscribed, Topic}}
end.
add_subscription_(undefined, Subscriber, Topic) ->
ets:insert(mqtt_subscription, {Subscriber, Topic});
add_subscription_(Share, Subscriber, Topic) ->
ets:insert(mqtt_subscription, {Subscriber, {Share, Topic}}).
monitor_subpid(SubPid, State = #state{submon = PMon}) when is_pid(SubPid) ->
State#state{submon = PMon:monitor(SubPid)};
monitor_subpid(_SubPid, State) ->
State.
do_unsubscribe_(Topic, Subscriber, State) ->
case ets:lookup(mqtt_subproperty, {Topic, Subscriber}) of
[{_, Options}] ->
emqttd_pubsub:async_unsubscribe(Topic, Subscriber, Options),
Share = proplists:get_value(share, Options),
del_subscription_(Share, Subscriber, Topic),
ets:delete(mqtt_subproperty, {Topic, Subscriber}),
{ok, case ets:member(mqtt_subscription, Subscriber) of
true -> State;
false -> demonitor_subpid(Subscriber, State)
end};
[] ->
{error, {subscription_not_found, Topic}}
end.
del_subscription_(undefined, Subscriber, Topic) ->
ets:delete_object(mqtt_subscription, {Subscriber, Topic});
del_subscription_(Share, Subscriber, Topic) ->
ets:delete_object(mqtt_subscription, {Subscriber, {Share, Topic}}).
demonitor_subpid(SubPid, State = #state{submon = PMon}) when is_pid(SubPid) ->
State#state{submon = PMon:demonitor(SubPid)};
demonitor_subpid(_SubPid, State) ->
State.
subscriber_down_(Subscriber) ->
lists:foreach(fun({_, {Share, Topic}}) ->
subscriber_down_(Share, Subscriber, Topic);
({_, Topic}) ->
subscriber_down_(undefined, Subscriber, Topic)
end, ets:lookup(mqtt_subscription, Subscriber)),
ets:delete(mqtt_subscription, Subscriber).
subscriber_down_(Share, Subscriber, Topic) ->
case ets:lookup(mqtt_subproperty, {Topic, Subscriber}) of
[] ->
%% TODO:....???
Options = if Share == undefined -> []; true -> [{share, Share}] end,
emqttd_pubsub:async_unsubscribe(Topic, Subscriber, Options);
[{_, Options}] ->
emqttd_pubsub:async_unsubscribe(Topic, Subscriber, Options),
ets:delete(mqtt_subproperty, {Topic, Subscriber})
end.
setstats(State) ->
emqttd_stats:setstats('subscriptions/count', 'subscriptions/max',
ets:info(mqtt_subscription, size)), State.