get session_id in filter

gistfile1.erl

filter_get_session_id(RequestContext) ->
    %% Get session_id from requestContext or Cookies
    case proplists:get_value(session_id, RequestContext) of
        undefined ->
            %% Try loading session_id from request, using boss_web_controller
            boss_web_controller:generate_session_id(proplists:get_value(request, RequestContext));
        SessionID ->
            SessionID
    end.