emqx/src/emqx_pool.erl

139 lines
3.6 KiB
Erlang

%%--------------------------------------------------------------------
%% Copyright (c) 2018-2022 EMQ Technologies Co., Ltd. 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(emqx_pool).
-behaviour(gen_server).
-include("logger.hrl").
-include("types.hrl").
-logger_header("[Pool]").
%% APIs
-export([start_link/2]).
-export([ submit/1
, submit/2
, async_submit/1
, async_submit/2
]).
-ifdef(TEST).
-export([worker/0]).
-endif.
%% gen_server callbacks
-export([ init/1
, handle_call/3
, handle_cast/2
, handle_info/2
, terminate/2
, code_change/3
]).
-define(POOL, ?MODULE).
-type(task() :: fun() | mfa() | {fun(), Args :: list(any())}).
%%--------------------------------------------------------------------
%% APIs
%%--------------------------------------------------------------------
%% @doc Start pool.
-spec(start_link(atom(), pos_integer()) -> startlink_ret()).
start_link(Pool, Id) ->
gen_server:start_link({local, emqx_misc:proc_name(?MODULE, Id)},
?MODULE, [Pool, Id], [{hibernate_after, 1000}]).
%% @doc Submit work to the pool.
-spec(submit(task()) -> any()).
submit(Task) ->
call({submit, Task}).
-spec(submit(fun(), list(any())) -> any()).
submit(Fun, Args) ->
call({submit, {Fun, Args}}).
%% @private
call(Req) ->
gen_server:call(worker(), Req, infinity).
%% @doc Submit work to the pool asynchronously.
-spec(async_submit(task()) -> ok).
async_submit(Task) ->
cast({async_submit, Task}).
-spec(async_submit(fun(), list(any())) -> ok).
async_submit(Fun, Args) ->
cast({async_submit, {Fun, Args}}).
%% @private
cast(Msg) ->
gen_server:cast(worker(), Msg).
%% @private
worker() ->
gproc_pool:pick_worker(?POOL).
%%--------------------------------------------------------------------
%% gen_server callbacks
%%--------------------------------------------------------------------
init([Pool, Id]) ->
true = gproc_pool:connect_worker(Pool, {Pool, Id}),
{ok, #{pool => Pool, id => Id}}.
handle_call({submit, Task}, _From, State) ->
{reply, catch run(Task), State};
handle_call(Req, _From, State) ->
?LOG(error, "Unexpected call: ~p", [Req]),
{reply, ignored, State}.
handle_cast({async_submit, Task}, State) ->
try run(Task)
catch _:Error:Stacktrace ->
?LOG(error, "Error: ~0p, ~0p", [Error, Stacktrace])
end,
{noreply, State};
handle_cast(Msg, State) ->
?LOG(error, "Unexpected cast: ~p", [Msg]),
{noreply, State}.
handle_info(Info, State) ->
?LOG(error, "Unexpected info: ~p", [Info]),
{noreply, State}.
terminate(_Reason, #{pool := Pool, id := Id}) ->
gproc_pool:disconnect_worker(Pool, {Pool, Id}).
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
%%--------------------------------------------------------------------
%% Internal functions
%%--------------------------------------------------------------------
run({M, F, A}) ->
erlang:apply(M, F, A);
run({F, A}) when is_function(F), is_list(A) ->
erlang:apply(F, A);
run(Fun) when is_function(Fun) ->
Fun().