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Diffstat (limited to 'apps/couch/src/couch_log.erl')
-rw-r--r-- | apps/couch/src/couch_log.erl | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/apps/couch/src/couch_log.erl b/apps/couch/src/couch_log.erl new file mode 100644 index 00000000..362d092d --- /dev/null +++ b/apps/couch/src/couch_log.erl @@ -0,0 +1,191 @@ +% 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). +-behaviour(gen_event). + +-export([start_link/0,stop/0]). +-export([debug/2, info/2, error/2]). +-export([debug_on/0,info_on/0,get_level/0,get_level_integer/0, set_level/1]). +-export([init/1, handle_event/2, terminate/2, code_change/3, handle_info/2, handle_call/2]). +-export([read/2]). + +-define(LEVEL_ERROR, 3). +-define(LEVEL_INFO, 2). +-define(LEVEL_DEBUG, 1). +-define(LEVEL_TMI, 0). + +debug(Format, Args) -> + {ConsoleMsg, FileMsg} = get_log_messages(self(), debug, Format, Args), + gen_event:sync_notify(error_logger, {couch_debug, ConsoleMsg, FileMsg}). + +info(Format, Args) -> + {ConsoleMsg, FileMsg} = get_log_messages(self(), info, Format, Args), + gen_event:sync_notify(error_logger, {couch_info, ConsoleMsg, FileMsg}). + +error(Format, Args) -> + {ConsoleMsg, FileMsg} = get_log_messages(self(), error, Format, Args), + gen_event:sync_notify(error_logger, {couch_error, ConsoleMsg, FileMsg}). + + +level_integer(error) -> ?LEVEL_ERROR; +level_integer(info) -> ?LEVEL_INFO; +level_integer(debug) -> ?LEVEL_DEBUG; +level_integer(tmi) -> ?LEVEL_TMI; +level_integer(_Else) -> ?LEVEL_ERROR. % anything else default to ERROR level + +level_atom(?LEVEL_ERROR) -> error; +level_atom(?LEVEL_INFO) -> info; +level_atom(?LEVEL_DEBUG) -> debug; +level_atom(?LEVEL_TMI) -> tmi. + + +start_link() -> + couch_event_sup:start_link({local, couch_log}, error_logger, couch_log, []). + +stop() -> + couch_event_sup:stop(couch_log). + +init([]) -> + % read config and register for configuration changes + + % just stop if one of the config settings change. couch_server_sup + % will restart us and then we will pick up the new settings. + ok = couch_config:register( + fun("log", "file") -> + ?MODULE:stop(); + ("log", "level") -> + ?MODULE:stop(); + ("log", "include_sasl") -> + ?MODULE:stop() + end), + + Filename = couch_config:get("log", "file", "couchdb.log"), + Level = level_integer(list_to_atom(couch_config:get("log", "level", "info"))), + Sasl = list_to_atom(couch_config:get("log", "include_sasl", "true")), + + case ets:info(?MODULE) of + undefined -> ets:new(?MODULE, [named_table]); + _ -> ok + end, + ets:insert(?MODULE, {level, Level}), + + case file:open(Filename, [append]) of + {ok, Fd} -> + {ok, {Fd, Level, Sasl}}; + {error, eacces} -> + {stop, {file_permission_error, Filename}}; + Error -> + {stop, Error} + end. + +debug_on() -> + get_level_integer() =< ?LEVEL_DEBUG. + +info_on() -> + get_level_integer() =< ?LEVEL_INFO. + +set_level(LevelAtom) -> + set_level_integer(level_integer(LevelAtom)). + +get_level() -> + level_atom(get_level_integer()). + +get_level_integer() -> + try + ets:lookup_element(?MODULE, level, 2) + catch error:badarg -> + ?LEVEL_ERROR + end. + +set_level_integer(Int) -> + gen_event:call(error_logger, couch_log, {set_level_integer, Int}). + +handle_event({couch_error, ConMsg, FileMsg}, {Fd, _LogLevel, _Sasl}=State) -> + log(Fd, ConMsg, FileMsg), + {ok, State}; +handle_event({couch_info, ConMsg, FileMsg}, {Fd, LogLevel, _Sasl}=State) +when LogLevel =< ?LEVEL_INFO -> + log(Fd, ConMsg, FileMsg), + {ok, State}; +handle_event({couch_debug, ConMsg, FileMsg}, {Fd, LogLevel, _Sasl}=State) +when LogLevel =< ?LEVEL_DEBUG -> + log(Fd, ConMsg, FileMsg), + {ok, State}; +handle_event({error_report, _, {Pid, _, _}}=Event, {Fd, _LogLevel, Sasl}=State) +when Sasl =/= false -> + {ConMsg, FileMsg} = get_log_messages(Pid, error, "~p", [Event]), + log(Fd, ConMsg, FileMsg), + {ok, State}; +handle_event({error, _, {Pid, Format, Args}}, {Fd, _LogLevel, Sasl}=State) +when Sasl =/= false -> + {ConMsg, FileMsg} = get_log_messages(Pid, error, Format, Args), + log(Fd, ConMsg, FileMsg), + {ok, State}; +handle_event({_, _, {Pid, _, _}}=Event, {Fd, LogLevel, _Sasl}=State) +when LogLevel =< ?LEVEL_TMI -> + % log every remaining event if tmi! + {ConMsg, FileMsg} = get_log_messages(Pid, tmi, "~p", [Event]), + log(Fd, ConMsg, FileMsg), + {ok, State}; +handle_event(_Event, State) -> + {ok, State}. + +handle_call({set_level_integer, NewLevel}, {Fd, _LogLevel, Sasl}) -> + ets:insert(?MODULE, {level, NewLevel}), + {ok, ok, {Fd, NewLevel, Sasl}}. + +handle_info(_Info, State) -> + {ok, State}. + +code_change(_OldVsn, State, _Extra) -> + {ok, State}. + +terminate(_Arg, {Fd, _LoggingLevel, _Sasl}) -> + file:close(Fd). + +log(Fd, ConsoleMsg, FileMsg) -> + ok = io:put_chars(ConsoleMsg), + ok = io:put_chars(Fd, FileMsg). + +get_log_messages(Pid, Level, Format, Args) -> + Nonce = case erlang:get(nonce) of + undefined -> "--------"; + Else -> Else + end, + ConsoleMsg = unicode:characters_to_binary(io_lib:format( + "[~s] [~p] [~s] " ++ Format ++ "~n", [Level, Pid, Nonce | Args])), + FileMsg = ["[", httpd_util:rfc1123_date(), "] ", ConsoleMsg], + {ConsoleMsg, iolist_to_binary(FileMsg)}. + +read(Bytes, Offset) -> + LogFileName = couch_config:get("log", "file"), + LogFileSize = filelib:file_size(LogFileName), + MaxChunkSize = list_to_integer( + couch_config:get("httpd", "log_max_chunk_size", "1000000")), + case Bytes > MaxChunkSize of + true -> + throw({bad_request, "'bytes' cannot exceed " ++ + integer_to_list(MaxChunkSize)}); + false -> + ok + end, + + {ok, Fd} = file:open(LogFileName, [read]), + Start = lists:max([LogFileSize - Bytes, 0]) + Offset, + + % TODO: truncate chopped first line + % TODO: make streaming + + {ok, Chunk} = file:pread(Fd, Start, LogFileSize), + ok = file:close(Fd), + Chunk. |