anchor.diff:  %% @end
   %%--------------------------------------------------------------------
   handle_call({activate}, _From, State) ->
  -    {reply, Reply, State#state{ status = activated }};
  +    {reply, ok, State#state{ status = activated }};
   handle_call({inactivate}, _From, State) ->
  -    {reply, Reply, State#state{ status = inactivated }};
  +    {reply, ok, State#state{ status = inactivated }};
   handle_call(_Request, _From, State) ->
       Reply = ok,
       {reply, Reply, State}.
  
positive.code: %%                                   {stop, Reason, State}
  %% @end
  %%--------------------------------------------------------------------
  handle_info(trigger_task, State = #state{ name = Name, status = inactivated }) ->
      lager:debug("Not Activated Task: ~ts", [Name]),
      {noreply, State};
  handle_info(trigger_task, State = #state{ status = activated, command = Cmd }) ->
      %% TODO: need notice result to barile server?
      %% TODO: schedule checkes
      case execute_cmd(Cmd) of
          {ok, Output} ->
              lager:debug("Succeed to execute command( ~p ): ~p", [State#state.command, Output]);
          {Reason, Output} ->
              lager:error("Failed to execute command( ~p ): ~p", [State#state.command, Output]);
      end,
      {noreply, State};
  handle_info(_Info, State) ->
      {noreply, State}.
  
  
negative.code: 
  %% API
  -export([start_link/3,
           inactivate/1,
           activate/1
          ]).
  
  %% gen_server callbacks
  