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%% Copyright (c) 2011-2012 Basho Technologies, Inc. All Rights Reserved.
%%
%% This file is provided to you 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.
%% @doc Console backend for lager. Configured with a single option, the loglevel
%% desired.
-module(lager_console_backend).
-behaviour(gen_event).
-export([init/1, handle_call/2, handle_event/2, handle_info/2, terminate/2,
code_change/3]).
-record(state, {level, formatter,format_config}).
-ifdef(TEST).
-include_lib("eunit/include/eunit.hrl").
-compile([{parse_transform, lager_transform}]).
-endif.
-include("lager.hrl").
-define(TERSE_FORMAT,[time, " [", severity,"] ", message, "\r\n"]).
%% @private
init([Level, true]) -> % for backwards compatibility
init([Level,{lager_default_formatter,[{eol, "\r\n"}]}]);
init([Level,false]) -> % for backwards compatibility
init([Level,{lager_default_formatter,?TERSE_FORMAT}]);
init([Level,{Formatter,FormatterConfig}]) when is_atom(Formatter) ->
try lager_util:config_to_mask(Level) of
Levels ->
{ok, #state{level=Levels,
formatter=Formatter,
format_config=FormatterConfig}}
catch
_:_ ->
{error, bad_log_level}
end;
init(Level) ->
init([Level,{lager_default_formatter,?TERSE_FORMAT}]).
%% @private
handle_call(get_loglevel, #state{level=Level} = State) ->
{ok, Level, State};
handle_call({set_loglevel, Level}, State) ->
try lager_util:config_to_mask(Level) of
Levels ->
{ok, ok, State#state{level=Levels}}
catch
_:_ ->
{ok, {error, bad_log_level}, State}
end;
handle_call(_Request, State) ->
{ok, ok, State}.
%% @private
handle_event({log, Message},
#state{level=L,formatter=Formatter,format_config=FormatConfig} = State) ->
case lager_util:is_loggable(Message, L, ?MODULE) of
true ->
io:put_chars(user, Formatter:format(Message,FormatConfig)),
{ok, State};
false ->
{ok, State}
end;
handle_event(_Event, State) ->
{ok, State}.
%% @private
handle_info(_Info, State) ->
{ok, State}.
%% @private
terminate(_Reason, _State) ->
ok.
%% @private
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
-ifdef(TEST).
console_log_test_() ->
%% tiny recursive fun that pretends to be a group leader
F = fun(Self) ->
fun() ->
YComb = fun(Fun) ->
receive
{io_request, From, ReplyAs, {put_chars, unicode, _Msg}} = Y ->
From ! {io_reply, ReplyAs, ok},
Self ! Y,
Fun(Fun);
Other ->
?debugFmt("unexpected message ~p~n", [Other]),
Self ! Other
end
end,
YComb(YComb)
end
end,
{foreach,
fun() ->
error_logger:tty(false),
application:load(lager),
application:set_env(lager, handlers, []),
application:set_env(lager, error_logger_redirect, false),
application:start(lager),
whereis(user)
end,
fun(User) ->
unregister(user),
register(user, User),
application:stop(lager),
error_logger:tty(true)
end,
[
{"regular console logging",
fun() ->
Pid = spawn(F(self())),
gen_event:add_handler(lager_event, lager_console_backend, info),
unregister(user),
register(user, Pid),
erlang:group_leader(Pid, whereis(lager_event)),
lager_config:set(loglevel, {element(2, lager_util:config_to_mask(info)), []}),
lager:log(info, self(), "Test message"),
receive
{io_request, From, ReplyAs, {put_chars, unicode, Msg}} ->
From ! {io_reply, ReplyAs, ok},
?assertMatch([_, "[info]", "Test message\r\n"], re:split(Msg, " ", [{return, list}, {parts, 3}]))
after
500 ->
?assert(false)
end
end
},
{"verbose console logging",
fun() ->
Pid = spawn(F(self())),
unregister(user),
register(user, Pid),
erlang:group_leader(Pid, whereis(lager_event)),
gen_event:add_handler(lager_event, lager_console_backend, [info, true]),
lager_config:set(loglevel, {element(2, lager_util:config_to_mask(info)), []}),
lager:info("Test message"),
lager:info("Test message"),
PidStr = pid_to_list(self()),
receive
{io_request, _, _, {put_chars, unicode, Msg}} ->
?assertMatch([_, _, "[info]", PidStr, _,"Test message\r\n"], re:split(Msg, "[ @]", [{return, list}, {parts, 6}]))
after
500 ->
?assert(false)
end
end
},
{"custom format console logging",
fun() ->
Pid = spawn(F(self())),
unregister(user),
register(user, Pid),
erlang:group_leader(Pid, whereis(lager_event)),
gen_event:add_handler(lager_event, lager_console_backend,
[info, {lager_default_formatter, [date,"#",time,"#",severity,"#",node,"#",pid,"#",
module,"#",function,"#",file,"#",line,"#",message,"\r\n"]}]),
lager_config:set(loglevel, {?INFO, []}),
lager:info("Test message"),
PidStr = pid_to_list(self()),
NodeStr = atom_to_list(node()),
ModuleStr = atom_to_list(?MODULE),
receive
{io_request, _, _, {put_chars, unicode, Msg}} ->
?assertMatch([_, _, "info", NodeStr, PidStr, ModuleStr, _, _, _, "Test message\r\n"],
re:split(Msg, "#", [{return, list}, {parts, 10}]))
after
500 ->
?assert(false)
end
end
},
{"tracing should work",
fun() ->
Pid = spawn(F(self())),
unregister(user),
register(user, Pid),
gen_event:add_handler(lager_event, lager_console_backend, info),
erlang:group_leader(Pid, whereis(lager_event)),
lager_config:set(loglevel, {element(2, lager_util:config_to_mask(info)), []}),
lager:debug("Test message"),
receive
{io_request, From, ReplyAs, {put_chars, unicode, _Msg}} ->
From ! {io_reply, ReplyAs, ok},
?assert(false)
after
500 ->
?assert(true)
end,
{ok, _} = lager:trace_console([{module, ?MODULE}]),
lager:debug("Test message"),
receive
{io_request, From1, ReplyAs1, {put_chars, unicode, Msg1}} ->
From1 ! {io_reply, ReplyAs1, ok},
?assertMatch([_, "[debug]", "Test message\r\n"], re:split(Msg1, " ", [{return, list}, {parts, 3}]))
after
500 ->
?assert(false)
end
end
},
{"tracing doesn't duplicate messages",
fun() ->
Pid = spawn(F(self())),
unregister(user),
register(user, Pid),
gen_event:add_handler(lager_event, lager_console_backend, info),
lager_config:set(loglevel, {element(2, lager_util:config_to_mask(info)), []}),
erlang:group_leader(Pid, whereis(lager_event)),
lager:debug("Test message"),
receive
{io_request, From, ReplyAs, {put_chars, unicode, _Msg}} ->
From ! {io_reply, ReplyAs, ok},
?assert(false)
after
500 ->
?assert(true)
end,
{ok, _} = lager:trace_console([{module, ?MODULE}]),
lager:error("Test message"),
receive
{io_request, From1, ReplyAs1, {put_chars, unicode, Msg1}} ->
From1 ! {io_reply, ReplyAs1, ok},
?assertMatch([_, "[error]", "Test message\r\n"], re:split(Msg1, " ", [{return, list}, {parts, 3}]))
after
1000 ->
?assert(false)
end,
%% make sure this event wasn't duplicated
receive
{io_request, From2, ReplyAs2, {put_chars, unicode, _Msg2}} ->
From2 ! {io_reply, ReplyAs2, ok},
?assert(false)
after
500 ->
?assert(true)
end
end
},
{"blacklisting a loglevel works",
fun() ->
Pid = spawn(F(self())),
unregister(user),
register(user, Pid),
gen_event:add_handler(lager_event, lager_console_backend, info),
lager_config:set(loglevel, {element(2, lager_util:config_to_mask(info)), []}),
lager:set_loglevel(lager_console_backend, '!=info'),
erlang:group_leader(Pid, whereis(lager_event)),
lager:debug("Test message"),
receive
{io_request, From1, ReplyAs1, {put_chars, unicode, Msg1}} ->
From1 ! {io_reply, ReplyAs1, ok},
?assertMatch([_, "[debug]", "Test message\r\n"], re:split(Msg1, " ", [{return, list}, {parts, 3}]))
after
1000 ->
?assert(false)
end,
%% info is blacklisted
lager:info("Test message"),
receive
{io_request, From2, ReplyAs2, {put_chars, unicode, _Msg2}} ->
From2 ! {io_reply, ReplyAs2, ok},
?assert(false)
after
500 ->
?assert(true)
end
end
},
{"whitelisting a loglevel works",
fun() ->
Pid = spawn(F(self())),
unregister(user),
register(user, Pid),
gen_event:add_handler(lager_event, lager_console_backend, info),
lager_config:set(loglevel, {element(2, lager_util:config_to_mask(info)), []}),
lager:set_loglevel(lager_console_backend, '=debug'),
erlang:group_leader(Pid, whereis(lager_event)),
lager:debug("Test message"),
receive
{io_request, From1, ReplyAs1, {put_chars, unicode, Msg1}} ->
From1 ! {io_reply, ReplyAs1, ok},
?assertMatch([_, "[debug]", "Test message\r\n"], re:split(Msg1, " ", [{return, list}, {parts, 3}]))
after
1000 ->
?assert(false)
end,
%% info is blacklisted
lager:error("Test message"),
receive
{io_request, From2, ReplyAs2, {put_chars, unicode, _Msg2}} ->
From2 ! {io_reply, ReplyAs2, ok},
?assert(false)
after
500 ->
?assert(true)
end
end
}
]
}.
set_loglevel_test_() ->
{foreach,
fun() ->
error_logger:tty(false),
application:load(lager),
application:set_env(lager, handlers, [{lager_console_backend, info}]),
application:set_env(lager, error_logger_redirect, false),
application:start(lager)
end,
fun(_) ->
application:stop(lager),
error_logger:tty(true)
end,
[
{"Get/set loglevel test",
fun() ->
?assertEqual(info, lager:get_loglevel(lager_console_backend)),
lager:set_loglevel(lager_console_backend, debug),
?assertEqual(debug, lager:get_loglevel(lager_console_backend)),
lager:set_loglevel(lager_console_backend, '!=debug'),
?assertEqual(info, lager:get_loglevel(lager_console_backend)),
lager:set_loglevel(lager_console_backend, '!=info'),
?assertEqual(debug, lager:get_loglevel(lager_console_backend)),
ok
end
},
{"Get/set invalid loglevel test",
fun() ->
?assertEqual(info, lager:get_loglevel(lager_console_backend)),
?assertEqual({error, bad_log_level},
lager:set_loglevel(lager_console_backend, fatfinger)),
?assertEqual(info, lager:get_loglevel(lager_console_backend))
end
}
]
}.
-endif.