emqx/apps/emqx_prometheus/src/emqx_prometheus_sup.erl

72 lines
2.3 KiB
Erlang

%%--------------------------------------------------------------------
%% Copyright (c) 2020-2023 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_prometheus_sup).
-behaviour(supervisor).
-export([
start_link/0,
start_child/1,
stop_child/1
]).
-export([init/1]).
%% Helper macro for declaring children of supervisor
-define(CHILD(Mod, Opts), #{
id => Mod,
start => {Mod, start_link, [Opts]},
restart => permanent,
shutdown => 5000,
type => worker,
modules => [Mod]
}).
start_link() ->
supervisor:start_link({local, ?MODULE}, ?MODULE, []).
-spec start_child(supervisor:child_spec() | atom()) -> ok.
start_child(ChildSpec) when is_map(ChildSpec) ->
assert_started(supervisor:start_child(?MODULE, ChildSpec));
start_child(Mod) when is_atom(Mod) ->
assert_started(supervisor:start_child(?MODULE, ?CHILD(Mod, []))).
-spec stop_child(any()) -> ok | {error, term()}.
stop_child(ChildId) ->
case supervisor:terminate_child(?MODULE, ChildId) of
ok -> supervisor:delete_child(?MODULE, ChildId);
{error, not_found} -> ok;
Error -> Error
end.
init([]) ->
Children =
case emqx_conf:get([prometheus, enable], false) of
false -> [];
true -> [?CHILD(emqx_prometheus, [])]
end,
{ok, {{one_for_one, 10, 3600}, Children}}.
%%--------------------------------------------------------------------
%% Internal functions
%%--------------------------------------------------------------------
assert_started({ok, _Pid}) -> ok;
assert_started({ok, _Pid, _Info}) -> ok;
assert_started({error, {already_started, _Pid}}) -> ok;
assert_started({error, Reason}) -> {error, Reason}.