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%%% Copyright (c) 2017, NORDUnet A/S.
%%% See LICENSE for licensing information.
-module(plopconfig).
-export([get_env/1, get_env/2, init_table/0, load_config/0]).
-define(PLOPCONFIG_TABLE, plopconfig).
init_table() ->
case ets:info(?PLOPCONFIG_TABLE) of
undefined ->
ok;
_ ->
ets:delete(?PLOPCONFIG_TABLE)
end,
ets:new(?PLOPCONFIG_TABLE, [set, public, named_table]),
load_config().
keys() ->
KeyList = lists:map(fun ({Key, _Value}) -> Key end,
ets:tab2list(?PLOPCONFIG_TABLE)),
sets:from_list(KeyList).
load_config() ->
{ok, Filename} = application:get_env(plop, plopconfig),
{ok, File} = file:consult(Filename),
OldKeys = keys(),
lists:foreach(
fun ({Key, Value}) ->
true = ets:insert(?PLOPCONFIG_TABLE, {Key, Value})
end, hd(File)),
NewKeys = keys(),
RemovedKeys = sets:subtract(OldKeys, NewKeys),
lists:foreach(fun (Key) ->
ets:delete(?PLOPCONFIG_TABLE, Key)
end, sets:to_list(RemovedKeys)),
lager:info("loaded config: new keys ~p old keys ~p removed keys ~p",
[sets:to_list(NewKeys),
sets:to_list(OldKeys),
sets:to_list(RemovedKeys)]),
ok.
get_env(Key, DefaultValue) ->
case get_env(Key) of
{ok, Value} ->
Value;
_ ->
DefaultValue
end.
get_env(Key) ->
case ets:lookup(?PLOPCONFIG_TABLE, Key) of
[{_, Value}] ->
{ok, Value};
[] ->
undefined
end.
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