blob: 9449b1e56d60a3fb873bac699dc65a208961f35e [file] [log] [blame]
% 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.
% Reads CouchDB's ini file and gets queried for configuration parameters.
% This module is initialized with a list of ini files that it consecutively
% reads Key/Value pairs from and saves them in an ets table. If more an one
% ini file is specified, the last one is used to write changes that are made
% with store/2 back to that ini file.
-module(config).
-behaviour(gen_server).
-vsn(1).
-export([start_link/1, stop/0, reload/0]).
-export([all/0]).
-export([get/1, get/2, get/3]).
-export([set/3, set/4, set/5]).
-export([delete/2, delete/3, delete/4]).
-export([get_integer/3, set_integer/3]).
-export([get_float/3, set_float/3]).
-export([get_boolean/3, set_boolean/3]).
-export([listen_for_changes/2]).
-export([subscribe_for_changes/1]).
-export([parse_ini_file/1]).
-export([init/1, terminate/2, code_change/3]).
-export([handle_call/3, handle_cast/2, handle_info/2]).
-record(config, {
notify_funs=[],
ini_files=undefined,
write_filename=undefined
}).
start_link(IniFiles) ->
gen_server:start_link({local, ?MODULE}, ?MODULE, IniFiles, []).
stop() ->
gen_server:cast(?MODULE, stop).
reload() ->
gen_server:call(?MODULE, reload).
all() ->
lists:sort(gen_server:call(?MODULE, all, infinity)).
get_integer(Section, Key, Default) when is_integer(Default) ->
try
to_integer(get(Section, Key, Default))
catch
error:badarg ->
Default
end.
set_integer(Section, Key, Value) when is_integer(Value) ->
set(Section, Key, integer_to_list(Value));
set_integer(_, _, _) ->
error(badarg).
to_integer(List) when is_list(List) ->
list_to_integer(List);
to_integer(Int) when is_integer(Int) ->
Int;
to_integer(Bin) when is_binary(Bin) ->
list_to_integer(binary_to_list(Bin)).
get_float(Section, Key, Default) when is_float(Default) ->
try
to_float(get(Section, Key, Default))
catch
error:badarg ->
Default
end.
set_float(Section, Key, Value) when is_float(Value) ->
set(Section, Key, float_to_list(Value));
set_float(_, _, _) ->
error(badarg).
to_float(List) when is_list(List) ->
list_to_float(List);
to_float(Float) when is_float(Float) ->
Float;
to_float(Int) when is_integer(Int) ->
list_to_float(integer_to_list(Int) ++ ".0");
to_float(Bin) when is_binary(Bin) ->
list_to_float(binary_to_list(Bin)).
get_boolean(Section, Key, Default) when is_boolean(Default) ->
try
to_boolean(get(Section, Key, Default))
catch
error:badarg ->
Default
end.
set_boolean(Section, Key, true) ->
set(Section, Key, "true");
set_boolean(Section, Key, false) ->
set(Section, Key, "false");
set_boolean(_, _, _) ->
error(badarg).
to_boolean(List) when is_list(List) ->
case list_to_existing_atom(List) of
true ->
true;
false ->
false;
_ ->
error(badarg)
end;
to_boolean(Bool) when is_boolean(Bool) ->
Bool.
get(Section) when is_binary(Section) ->
?MODULE:get(binary_to_list(Section));
get(Section) when is_list(Section) ->
Matches = ets:match(?MODULE, {{Section, '$1'}, '$2'}),
[{Key, Value} || [Key, Value] <- Matches].
get(Section, Key) ->
?MODULE:get(Section, Key, undefined).
get(Section, Key, Default) when is_binary(Section) and is_binary(Key) ->
?MODULE:get(binary_to_list(Section), binary_to_list(Key), Default);
get(Section, Key, Default) when is_list(Section), is_list(Key) ->
case ets:lookup(?MODULE, {Section, Key}) of
[] when Default == undefined -> Default;
[] when is_boolean(Default) -> Default;
[] when is_float(Default) -> Default;
[] when is_integer(Default) -> Default;
[] when is_list(Default) -> Default;
[] when is_atom(Default) -> Default;
[] -> error(badarg);
[{_, Match}] -> Match
end.
set(Section, Key, Value) ->
?MODULE:set(Section, Key, Value, true, nil).
set(Section, Key, Value, Persist) when is_boolean(Persist) ->
?MODULE:set(Section, Key, Value, Persist, nil);
set(Section, Key, Value, Reason) ->
?MODULE:set(Section, Key, Value, true, Reason).
set(Sec, Key, Val, Persist, Reason) when is_binary(Sec) and is_binary(Key) ->
?MODULE:set(binary_to_list(Sec), binary_to_list(Key), Val, Persist, Reason);
set(Section, Key, Value, Persist, Reason)
when is_list(Section), is_list(Key), is_list(Value) ->
gen_server:call(?MODULE, {set, Section, Key, Value, Persist, Reason});
set(_Sec, _Key, _Val, _Persist, _Reason) ->
error(badarg).
delete(Section, Key) when is_binary(Section) and is_binary(Key) ->
delete(binary_to_list(Section), binary_to_list(Key));
delete(Section, Key) ->
delete(Section, Key, true, nil).
delete(Section, Key, Persist) when is_boolean(Persist) ->
delete(Section, Key, Persist, nil);
delete(Section, Key, Reason) ->
delete(Section, Key, true, Reason).
delete(Sec, Key, Persist, Reason) when is_binary(Sec) and is_binary(Key) ->
delete(binary_to_list(Sec), binary_to_list(Key), Persist, Reason);
delete(Section, Key, Persist, Reason) when is_list(Section), is_list(Key) ->
gen_server:call(?MODULE, {delete, Section, Key, Persist, Reason}).
listen_for_changes(CallbackModule, InitialState) ->
config_listener_mon:subscribe(CallbackModule, InitialState).
subscribe_for_changes(Subscription) ->
config_notifier:subscribe(Subscription).
init(IniFiles) ->
ets:new(?MODULE, [named_table, set, protected, {read_concurrency, true}]),
lists:map(fun(IniFile) ->
{ok, ParsedIniValues} = parse_ini_file(IniFile),
ets:insert(?MODULE, ParsedIniValues)
end, IniFiles),
WriteFile = case IniFiles of
[_|_] -> lists:last(IniFiles);
_ -> undefined
end,
debug_config(),
{ok, #config{ini_files=IniFiles, write_filename=WriteFile}}.
terminate(_Reason, _State) ->
ok.
handle_call(all, _From, Config) ->
Resp = lists:sort((ets:tab2list(?MODULE))),
{reply, Resp, Config};
handle_call({set, Sec, Key, Val, Persist, Reason}, _From, Config) ->
true = ets:insert(?MODULE, {{Sec, Key}, Val}),
couch_log:notice("~p: [~s] ~s set to ~s for reason ~p",
[?MODULE, Sec, Key, Val, Reason]),
case {Persist, Config#config.write_filename} of
{true, undefined} ->
ok;
{true, FileName} ->
config_writer:save_to_file({{Sec, Key}, Val}, FileName);
_ ->
ok
end,
Event = {config_change, Sec, Key, Val, Persist},
gen_event:sync_notify(config_event, Event),
{reply, ok, Config};
handle_call({delete, Sec, Key, Persist, Reason}, _From, Config) ->
true = ets:delete(?MODULE, {Sec,Key}),
couch_log:notice("~p: [~s] ~s deleted for reason ~p",
[?MODULE, Sec, Key, Reason]),
case {Persist, Config#config.write_filename} of
{true, undefined} ->
ok;
{true, FileName} ->
config_writer:save_to_file({{Sec, Key}, ""}, FileName);
_ ->
ok
end,
Event = {config_change, Sec, Key, deleted, Persist},
gen_event:sync_notify(config_event, Event),
{reply, ok, Config};
handle_call(reload, _From, Config) ->
DiskKVs = lists:foldl(fun(IniFile, DiskKVs0) ->
{ok, ParsedIniValues} = parse_ini_file(IniFile),
lists:foldl(fun({K, V}, DiskKVs1) ->
dict:store(K, V, DiskKVs1)
end, DiskKVs0, ParsedIniValues)
end, dict:new(), Config#config.ini_files),
% Update ets with anything we just read
% from disk
dict:fold(fun(K, V, _) ->
ets:insert(?MODULE, {K, V})
end, nil, DiskKVs),
% And remove anything in ets that wasn't
% on disk.
ets:foldl(fun({K, _}, _) ->
case dict:is_key(K, DiskKVs) of
true ->
ok;
false ->
ets:delete(?MODULE, K)
end
end, nil, ?MODULE),
{reply, ok, Config}.
handle_cast(stop, State) ->
{stop, normal, State};
handle_cast(_Msg, State) ->
{noreply, State}.
handle_info(Info, State) ->
couch_log:error("config:handle_info Info: ~p~n", [Info]),
{noreply, State}.
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
parse_ini_file(IniFile) ->
IniFilename = config_util:abs_pathname(IniFile),
IniBin =
case file:read_file(IniFilename) of
{ok, IniBin0} ->
IniBin0;
{error, enoent} ->
Fmt = "Couldn't find server configuration file ~s.",
Msg = list_to_binary(io_lib:format(Fmt, [IniFilename])),
couch_log:error("~s~n", [Msg]),
throw({startup_error, Msg})
end,
Lines = re:split(IniBin, "\r\n|\n|\r|\032", [{return, list}]),
{_, ParsedIniValues} =
lists:foldl(fun(Line, {AccSectionName, AccValues}) ->
case string:strip(Line) of
"[" ++ Rest ->
case re:split(Rest, "\\]", [{return, list}]) of
[NewSectionName, ""] ->
{NewSectionName, AccValues};
_Else -> % end bracket not at end, ignore this line
{AccSectionName, AccValues}
end;
";" ++ _Comment ->
{AccSectionName, AccValues};
Line2 ->
case re:split(Line2, "\s?=\s?", [{return, list}]) of
[Value] ->
MultiLineValuePart = case re:run(Line, "^ \\S", []) of
{match, _} ->
true;
_ ->
false
end,
case {MultiLineValuePart, AccValues} of
{true, [{{_, ValueName}, PrevValue} | AccValuesRest]} ->
% remove comment
case re:split(Value, " ;|\t;", [{return, list}]) of
[[]] ->
% empty line
{AccSectionName, AccValues};
[LineValue | _Rest] ->
E = {{AccSectionName, ValueName},
PrevValue ++ " " ++ LineValue},
{AccSectionName, [E | AccValuesRest]}
end;
_ ->
{AccSectionName, AccValues}
end;
[""|_LineValues] -> % line begins with "=", ignore
{AccSectionName, AccValues};
[ValueName|LineValues] -> % yeehaw, got a line!
RemainingLine = config_util:implode(LineValues, "="),
% removes comments
case re:split(RemainingLine, " ;|\t;", [{return, list}]) of
[[]] ->
% empty line means delete this key
ets:delete(?MODULE, {AccSectionName, ValueName}),
{AccSectionName, AccValues};
[LineValue | _Rest] ->
{AccSectionName,
[{{AccSectionName, ValueName}, LineValue} | AccValues]}
end
end
end
end, {"", []}, Lines),
{ok, ParsedIniValues}.
debug_config() ->
case ?MODULE:get("log", "level") of
"debug" ->
io:format("Configuration Settings:~n", []),
lists:foreach(fun({{Mod, Key}, Val}) ->
io:format(" [~s] ~s=~p~n", [Mod, Key, Val])
end, lists:sort(ets:tab2list(?MODULE)));
_ ->
ok
end.
-ifdef(TEST).
-include_lib("eunit/include/eunit.hrl").
to_integer_test() ->
?assertEqual(1, to_integer(1)),
?assertEqual(1, to_integer(<<"1">>)),
?assertEqual(1, to_integer("1")),
?assertEqual(-1, to_integer("-01")),
?assertEqual(0, to_integer("-0")),
?assertEqual(0, to_integer("+0")),
ok.
to_float_test() ->
?assertEqual(1.0, to_float(1)),
?assertEqual(1.0, to_float(<<"1.0">>)),
?assertEqual(1.0, to_float("1.0")),
?assertEqual(-1.1, to_float("-01.1")),
?assertEqual(0.0, to_float("-0.0")),
?assertEqual(0.0, to_float("+0.0")),
ok.
-endif.