anchor.diff:      return_json_credential_list(CredList);
   perform_get(credential, undefined, Session, _) ->
       {ok, CredList} = tts:get_credential_list_for(Session),
  -    return_json_credential_list(CredList, [cred_id, ctime, interface, service_id]);
  +    Keys = [cred_id, ctime, interface, service_id],
  +    return_json_credential_list(CredList, Keys);
   perform_get(cred_data, Id, Session, 1) ->
       case tts:get_temp_cred(Id, Session) of
           {ok, Cred} -> jsx:encode(Cred);
  
positive.code: end_session_if_rest(_) ->
      ok.
  
  
  
  perform_logout(Session) ->
  
negative.code: 
  
  get_json(Req, #state{version=Version, type=Type, id=Id, method=get,
                       session_pid=Session} = State) ->
      Result = perform_get(Type, Id, Session, Version),
      ok = end_session_if_rest(State),
      {ok, Req2} = update_cookie_if_used(Req, State),
      {Result, Req2, State#state{session_pid=undefined}}.
  
  
  post_json(Req, #state{version=Version, type=Type, id=Id, method=post,
  