Erlang gen_server and supervisor template

test.erl

-module(test).
-export([start_link/0]).

-behaviour(gen_server).
-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]).

-define(SERVER, ?MODULE).

start_link() ->
    gen_server:start_link({local, ?SERVER}, ?MODULE, {}, []).

%% @private
init({}) ->
    {ok, undefined}.


% here the function to handle the test_function call with params
handle_call({test_function, Params}, _From, State) ->
    Reply = [],
    {reply, Reply, State}.

%% @private
handle_call(_Request, _From, State) ->
    {reply, {error, unknown_call}, State}.

%% @private
handle_cast(_Msg, State) ->
    {noreply, State}.

%% @private
handle_info(_Info, State) ->
    {noreply, State}.

%% @private
terminate(_Reason, _State) ->
    ok.

%% @private
code_change(_OldVsn, State, _Extra) ->
    {ok, State}.



test_function(Params) ->
    gen_server:call(?MODULE, {test_function, Params}).

test_sup.erl

-module(test_sup).

-export([start_link/0]).

-behaviour(supervisor).
-export([init/1]).

-define(SERVER, ?MODULE).

start_link() ->
    supervisor:start_link({local, ?SERVER}, ?MODULE, {}).

%% @private
init({}) ->
    Worker = {test, {test, start_link, []}, permanent, 5000, worker, [test]},
            % {Tag,       {Mod,        Fun,   ArgList}, Restart  , Shutdown, Type, [Mod]     },
            % Restart : permanent | transient | temporary
            %   permanent : always restart
            %   transient : restart only if terminates with a non-normal exit value
            %
            % Shutdown :
            %   if takes longer than this value to terminate, it will be killed.
    Workers = [Worker],
    RestartStrategy = {one_for_one, 5, 10},
    {ok, {RestartStrategy, Workers}}.

thanks a ton for this !