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%% ========================== Config API ============================
%% The default implementation uses the application environment to
%% store configuration. There is a simple wrapper module to interface
%% with configuration store (otters_config). To implementat other config
%% persistence, the module should be replaced with another one providing
%% the same simple read/write API functions.
%% WARNING : In the default implementation using the application
%% environment, so the write function is NOT persistent. In case of node
%% restart and/or application reload the configuration will be reset to
%% whatever environment is defined in the release (sys) config or app
%% file. There is an example configuration provided in the otters.app
%% file as a reference.

-module(otters_config).
-export([
         list/0,
         read/1,
         read/2,
         write/2
        ]).

list() ->
    application:get_all_env(otters).

read(Key) ->
    application:get_env(otters, Key).

read(Key, Default) ->
    application:get_env(otters, Key, Default).

%% This is provided to allow temporary configuration. Obviously in this
%% default implementation it is not persistent as application environment
%% from either the .app file in the ebin directory or from the release
%% specific sys.config (or alike) will be read at startup.
write(Key, Value) ->
    application:set_env(otters, Key, Value).