dgiot/src/emqx_app.erl
2021-08-16 15:07:42 +08:00

138 lines
3.8 KiB
Erlang

%%--------------------------------------------------------------------
%% Copyright (c) 2017-2021 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_app).
-behaviour(application).
-export([ start/2
, prep_stop/1
, stop/1
, get_description/0
, get_release/0
]).
-define(APP, emqx).
-include("emqx_release.hrl").
%%--------------------------------------------------------------------
%% Application callbacks
%%--------------------------------------------------------------------
start(_Type, _Args) ->
set_backtrace_depth(),
print_otp_version_warning(),
print_banner(),
%% Load application first for ekka_mnesia scanner
_ = load_ce_modules(),
ekka:start(),
{ok, Sup} = emqx_sup:start_link(),
ok = start_autocluster(),
ok = emqx_plugins:init(),
_ = emqx_plugins:load(),
_ = start_ce_modules(),
emqx_boot:is_enabled(listeners) andalso (ok = emqx_listeners:start()),
register(emqx, self()),
ok = emqx_alarm_handler:load(),
print_vsn(),
{ok, Sup}.
prep_stop(_State) ->
ok = emqx_alarm_handler:unload(),
emqx_boot:is_enabled(listeners)
andalso emqx_listeners:stop().
stop(_State) ->
ok.
set_backtrace_depth() ->
Depth = application:get_env(?APP, backtrace_depth, 16),
_ = erlang:system_flag(backtrace_depth, Depth),
ok.
-ifndef(EMQX_ENTERPRISE).
load_ce_modules() ->
application:load(emqx_modules).
start_ce_modules() ->
application:ensure_all_started(emqx_modules).
-else.
load_ce_modules() ->
ok.
start_ce_modules() ->
ok.
-endif.
%%--------------------------------------------------------------------
%% Print Banner
%%--------------------------------------------------------------------
-if(?OTP_RELEASE> 22).
print_otp_version_warning() -> ok.
-else.
print_otp_version_warning() ->
io:format("WARNING: Running on Erlang/OTP version ~p. Recommended: 23~n",
[?OTP_RELEASE]).
-endif. % OTP_RELEASE
-ifndef(TEST).
print_banner() ->
io:format("Starting ~s on node ~s~n", [?APP, node()]).
print_vsn() ->
io:format("~s ~s is running now!~n", [get_description(), get_release()]).
-else. % TEST
print_vsn() ->
ok.
print_banner() ->
ok.
-endif. % TEST
get_description() ->
{ok, Descr0} = application:get_key(?APP, description),
case os:getenv("EMQX_DESCRIPTION") of
false -> Descr0;
"" -> Descr0;
Str -> string:strip(Str, both, $\n)
end.
get_release() ->
case lists:keyfind(emqx_vsn, 1, ?MODULE:module_info(compile)) of
false -> %% For TEST build or depedency build.
release_in_macro();
{_, Vsn} -> %% For emqx release build
VsnStr = release_in_macro(),
1 = string:str(Vsn, VsnStr), %% assert
Vsn
end.
release_in_macro() ->
element(2, ?EMQX_RELEASE).
%%--------------------------------------------------------------------
%% Autocluster
%%--------------------------------------------------------------------
start_autocluster() ->
ekka:callback(prepare, fun emqx:shutdown/1),
ekka:callback(reboot, fun emqx:reboot/0),
_ = ekka:autocluster(?APP), %% returns 'ok' or a pid or 'any()' as in spec
ok.