%% -*- erlang-indent-level: 4; indent-tabs-mode: nil; fill-column: 80 -*- %%% Copyright 2012 Erlware, LLC. 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. %%%--------------------------------------------------------------------------- %%% @author Eric Merritt %%% @copyright (C) 2012 Erlware, LLC. %%% %%% @doc This provides simple output functions for relx. You should use this %%% to talk to the users if you are wrting code for the system -module(rlx_log). -export([new/1, new/2, log/4, should/2, debug/2, debug/3, info/2, info/3, error/2, error/3, log_level/1, atom_log_level/1, format/1]). -export_type([t/0, int_log_level/0, atom_log_level/0, log_level/0, log_fun/0]). -include_lib("relx/include/relx.hrl"). -define(RED, 31). -define(GREEN, 32). -define(YELLOW, 33). -define(BLUE, 34). -define(MAGENTA, 35). -define(CYAN, 36). -define(PREFIX, "===> "). -record(state_t, {mod=?MODULE :: rlx_log, log_level=0 :: int_log_level(), caller=api :: api | command_line}). %%============================================================================ %% types %%============================================================================ -type log_level() :: int_log_level() | atom_log_level(). -type int_log_level() :: 0..2. %% Why no warn? because for our purposes there is no difference between error %% and warn -type atom_log_level() :: error | info | debug. -type log_fun() :: fun(() -> iolist()). -type color() :: 31..36. -opaque t() :: record(state_t). %%============================================================================ %% API %%============================================================================ %% @doc Create a new 'log level' for the system -spec new(log_level()) -> t(). new(LogLevel) -> new(LogLevel, api). new(LogLevel, Caller) when LogLevel >= 0, LogLevel =< 2 -> #state_t{mod=?MODULE, log_level=LogLevel, caller=Caller}; new(AtomLogLevel, Caller) when AtomLogLevel =:= error; AtomLogLevel =:= info; AtomLogLevel =:= debug -> LogLevel = case AtomLogLevel of error -> 0; info -> 1; debug -> 2 end, new(LogLevel, Caller). %% @doc log at the debug level given the current log state with a string or %% function that returns a string -spec debug(t(), string() | log_fun()) -> ok. debug(LogState, Fun) when erlang:is_function(Fun) -> log(LogState, ?RLX_DEBUG, fun() -> colorize(LogState, ?CYAN, false, Fun()) end); debug(LogState, String) -> debug(LogState, "~s~n", [String]). %% @doc log at the debug level given the current log state with a format string %% and argements @see io:format/2 -spec debug(t(), string(), [any()]) -> ok. debug(LogState, FormatString, Args) -> log(LogState, ?RLX_DEBUG, colorize(LogState, ?CYAN, false, FormatString), Args). %% @doc log at the info level given the current log state with a string or %% function that returns a string -spec info(t(), string() | log_fun()) -> ok. info(LogState, Fun) when erlang:is_function(Fun) -> log(LogState, ?RLX_INFO, fun() -> colorize(LogState, ?GREEN, false, Fun()) end); info(LogState, String) -> info(LogState, "~s~n", [String]). %% @doc log at the info level given the current log state with a format string %% and argements @see io:format/2 -spec info(t(), string(), [any()]) -> ok. info(LogState, FormatString, Args) -> log(LogState, ?RLX_INFO, colorize(LogState, ?GREEN, false, FormatString), Args). %% @doc log at the error level given the current log state with a string or %% format string that returns a function -spec error(t(), string() | log_fun()) -> ok. error(LogState, Fun) when erlang:is_function(Fun) -> log(LogState, ?RLX_ERROR, fun() -> colorize(LogState, ?RED, false, Fun()) end); error(LogState, String) -> error(LogState, "~s~n", [String]). %% @doc log at the error level given the current log state with a format string %% and argements @see io:format/2 -spec error(t(), string(), [any()]) -> ok. error(LogState, FormatString, Args) -> log(LogState, ?RLX_ERROR, colorize(LogState, ?GREEN, false, FormatString), Args). %% @doc Execute the fun passed in if log level is as expected. -spec log(t(), int_log_level(), log_fun()) -> ok. log(#state_t{mod=?MODULE, log_level=DetailLogLevel}, LogLevel, Fun) when DetailLogLevel >= LogLevel -> io:format("~s~n", [Fun()]); log(_, _, _) -> ok. %% @doc when the module log level is less then or equal to the log level for the %% call then write the log info out. When its not then ignore the call. -spec log(t(), int_log_level(), string(), [any()]) -> ok. log(#state_t{mod=?MODULE, log_level=DetailLogLevel}, LogLevel, FormatString, Args) when DetailLogLevel >= LogLevel, erlang:is_list(Args) -> io:format(FormatString, Args); log(_, _, _, _) -> ok. %% @doc return a boolean indicating if the system should log for the specified %% levelg -spec should(t(), int_log_level() | any()) -> boolean(). should(#state_t{mod=?MODULE, log_level=DetailLogLevel}, LogLevel) when DetailLogLevel >= LogLevel -> true; should(_, _) -> false. %% @doc get the current log level as an integer -spec log_level(t()) -> int_log_level(). log_level(#state_t{mod=?MODULE, log_level=DetailLogLevel}) -> DetailLogLevel. %% @doc get the current log level as an atom -spec atom_log_level(t()) -> atom_log_level(). atom_log_level(#state_t{mod=?MODULE, log_level=?RLX_ERROR}) -> error; atom_log_level(#state_t{mod=?MODULE, log_level=?RLX_INFO}) -> info; atom_log_level(#state_t{mod=?MODULE, log_level=?RLX_DEBUG}) -> debug. -spec format(t()) -> iolist(). format(Log) -> [<<"(">>, erlang:integer_to_list(log_level(Log)), <<":">>, erlang:atom_to_list(atom_log_level(Log)), <<")">>]. -spec colorize(t(), color(), boolean(), string()) -> string(). colorize(#state_t{caller=command_line}, Color, false, Msg) when is_integer(Color) -> colorize_(Color, 0, Msg); colorize(_LogState, _Color, _Bold, Msg) -> Msg. -spec colorize_(color(), integer(), string()) -> string(). colorize_(Color, Bold, Msg) when is_integer(Color), is_integer(Bold)-> lists:flatten(io_lib:format("\033[~B;~Bm~s~s\033[0m", [Bold, Color, ?PREFIX, Msg])). %%%=================================================================== %%% Test Functions %%%=================================================================== -ifndef(NOTEST). -include_lib("eunit/include/eunit.hrl"). should_test() -> ErrorLogState = new(error), ?assertMatch(true, should(ErrorLogState, ?RLX_ERROR)), ?assertMatch(true, not should(ErrorLogState, ?RLX_INFO)), ?assertMatch(true, not should(ErrorLogState, ?RLX_DEBUG)), ?assertEqual(?RLX_ERROR, log_level(ErrorLogState)), ?assertEqual(error, atom_log_level(ErrorLogState)), InfoLogState = new(info), ?assertMatch(true, should(InfoLogState, ?RLX_ERROR)), ?assertMatch(true, should(InfoLogState, ?RLX_INFO)), ?assertMatch(true, not should(InfoLogState, ?RLX_DEBUG)), ?assertEqual(?RLX_INFO, log_level(InfoLogState)), ?assertEqual(info, atom_log_level(InfoLogState)), DebugLogState = new(debug), ?assertMatch(true, should(DebugLogState, ?RLX_ERROR)), ?assertMatch(true, should(DebugLogState, ?RLX_INFO)), ?assertMatch(true, should(DebugLogState, ?RLX_DEBUG)), ?assertEqual(?RLX_DEBUG, log_level(DebugLogState)), ?assertEqual(debug, atom_log_level(DebugLogState)). -endif.