| % 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}. |