anchor.diff:  
   -include_lib("emqtt/include/emqtt.hrl").
   
  +-include("emqttd.hrl").
  +
   -behaviour(gen_server).
   
   -define(SERVER, ?MODULE).
  
positive.code: %%% gen_server callbacks
  %%%=============================================================================
  init([]) ->
      {ok, #state{}, hibernate}.
  
  handle_call(_Request, _From, State) ->
      {reply, ok, State}.
  
negative.code: %%Router Chain--> --->In Out<---
  -export([route/2]).
  
  %% Mnesia Callbacks
  -export([mnesia/1]).
  
  -boot_mnesia({mnesia, [boot]}).
  -copy_mnesia({mnesia, [copy]}).
  
  %% gen_server Function Exports
  -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
           terminate/2, code_change/3]).
  
  -record(state, {}).
  
  %%%=============================================================================
  %%% Mnesia callbacks
  %%%=============================================================================
  mnesia(boot) ->
      %% topic table
      ok = emqttd_mnesia:create_table(topic, [
                  {type, bag},
                  {ram_copies, [node()]},
                  {record_name, mqtt_topic},
                  {attributes, record_info(fields, mqtt_topic)}]).
  
  mnesia(copy) ->
      ok = emqttd_mnesia:copy_table(topic),
  
  %%%=============================================================================
  %%% API
  