emqx/src/emqttd_pooler.erl

99 lines
2.9 KiB
Erlang

%%--------------------------------------------------------------------
%% Copyright (c) 2013-2017 EMQ Enterprise, Inc.
%%
%% 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_pooler).
-behaviour(gen_server).
-include("emqttd_internal.hrl").
%% Start the pool supervisor
-export([start_link/0]).
%% API Exports
-export([start_link/2, submit/1, async_submit/1]).
%% gen_server Function Exports
-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
terminate/2, code_change/3]).
-record(state, {pool, id}).
%% @doc Start Pooler Supervisor.
start_link() ->
emqttd_pool_sup:start_link(pooler, random, {?MODULE, start_link, []}).
%%--------------------------------------------------------------------
%% API
%%--------------------------------------------------------------------
-spec(start_link(atom(), pos_integer()) -> {ok, pid()} | ignore | {error, any()}).
start_link(Pool, Id) ->
gen_server:start_link({local, ?PROC_NAME(?MODULE, Id)}, ?MODULE, [Pool, Id], []).
%% @doc Submit work to pooler
submit(Fun) -> gen_server:call(worker(), {submit, Fun}, infinity).
%% @doc Submit work to pooler asynchronously
async_submit(Fun) ->
gen_server:cast(worker(), {async_submit, Fun}).
worker() ->
gproc_pool:pick_worker(pooler).
%%--------------------------------------------------------------------
%% gen_server callbacks
%%--------------------------------------------------------------------
init([Pool, Id]) ->
?GPROC_POOL(join, Pool, Id),
{ok, #state{pool = Pool, id = Id}}.
handle_call({submit, Fun}, _From, State) ->
{reply, run(Fun), State};
handle_call(_Req, _From, State) ->
{reply, ok, State}.
handle_cast({async_submit, Fun}, State) ->
try run(Fun)
catch _:Error ->
lager:error("Pooler Error: ~p, ~p", [Error, erlang:get_stacktrace()])
end,
{noreply, State};
handle_cast(_Msg, State) ->
{noreply, State}.
handle_info(_Info, State) ->
{noreply, State}.
terminate(_Reason, #state{pool = Pool, id = Id}) ->
?GPROC_POOL(leave, Pool, Id), ok.
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
%%--------------------------------------------------------------------
%% Internal functions
%%--------------------------------------------------------------------
run({M, F, A}) ->
erlang:apply(M, F, A);
run(Fun) when is_function(Fun) ->
Fun().