laravel5通过auth.attempt事件加入登陆验证码

<?php namespace WangDong\Http\Controllers\Auth;

use Illuminate\Http\Exception\HttpResponseException;
use Illuminate\Http\Request;
use WangDong\Http\Controllers\Controller;
use Illuminate\Contracts\Auth\Guard;
use Illuminate\Contracts\Auth\Registrar;
use Illuminate\Foundation\Auth\AuthenticatesAndRegistersUsers;

class AuthController extends Controller {

    /*
    |--------------------------------------------------------------------------
    | Registration & Login Controller
    |--------------------------------------------------------------------------
    |
    | This controller handles the registration of new users, as well as the
    | authentication of existing users. By default, this controller uses
    | a simple trait to add these behaviors. Why don‘t you explore it?
    |
    */

    use AuthenticatesAndRegistersUsers;

    /**
     * Create a new authentication controller instance.
     *
     * @param  \Illuminate\Contracts\Auth\Guard  $auth
     * @param  \Illuminate\Contracts\Auth\Registrar  $registrar
     * @return void
     */
    public function __construct(Guard $auth, Registrar $registrar,Request $request)
    {
        $this->auth = $auth;
        $this->registrar = $registrar;
        //注册auth.attemp事件
        //加入验证码的验证
        $this->auth->attempting(function()use($request){
            $phrase = \Session::get(‘phrase‘);
            if($request->input(‘phrase‘) != $phrase){
                throw new HttpResponseException(
                    redirect(‘/auth/login‘)->withInput($request->input())->withErrors([‘phrase‘=>‘验证码错误‘])
                );
            }
        });
        $this->middleware(‘guest‘, [‘except‘ => ‘getLogout‘]);
    }

}