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% 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(couch_log_monitor).
-behaviour(gen_server).
-vsn(1).
-export([
start_link/0
]).
-export([
init/1,
terminate/2,
handle_call/3,
handle_cast/2,
handle_info/2,
code_change/3
]).
-define(HANDLER_MOD, couch_log_error_logger_h).
start_link() ->
gen_server:start_link(?MODULE, [], []).
% OTP_RELEASE defined in OTP >= 21 only
-ifdef(OTP_RELEASE).
init(_) ->
% See https://erlang.org/doc/man/error_logger.html#add_report_handler-1
% however that call doesn't call a supervised handler so we do the same
% thing add_report_handler/1 does but call gen_event:add_sup_handler/3
% instead of gen_event:add_handler/3.
Opts = #{level => info, filter_default => log},
_ = logger:add_handler(error_logger, error_logger, Opts),
ok = gen_event:add_sup_handler(error_logger, ?HANDLER_MOD, []),
{ok, nil}.
-else.
init(_) ->
error_logger:start(),
ok = gen_event:add_sup_handler(error_logger, ?HANDLER_MOD, []),
{ok, nil}.
-endif.
terminate(_, _) ->
ok.
handle_call(_Msg, _From, St) ->
{reply, ignored, St}.
handle_cast(_Msg, St) ->
{noreply, St}.
handle_info({gen_event_EXIT, ?HANDLER_MOD, Reason}, St) ->
{stop, Reason, St};
handle_info(_Msg, St) ->
{noreply, St}.
code_change(_, State, _) ->
{ok, State}.
|
