Php Laravel JWT验证错误

我试图在Laravel 5.2中实现JWT，但我遇到了以下错误：

"message": "call_user_func_array() expects parameter 1 to be a valid callback, class 'Illuminate\\Auth\\TokenGuard' does not have a method 'once'",
  "status_code": 500,
  "debug": {
    "line": 288,
    "file": "/home/vagrant/Code/lsupport/vendor/laravel/framework/src/Illuminate/Auth/AuthManager.php",
    "class": "ErrorException",

我的路由文件：

$api = app('Dingo\Api\Routing\Router');

$api->version('v1',function($api)
{
    $api->post('login','App\Http\Controllers\Auth\AuthController@authenticate');
});

我的AuthController：

 public function authenticate(Request $request)
    {
        $credentials = $request->only('email','password');

        try {
            if(!$token = JWTAuth::attempt($credentials)) {
                return $this->response->error(['error' => 'User credentials are not correct!'],401);
            }
        } catch(JWTException $ex) {
            return $this->response->error(['error' => 'Something went wrong!'],500);
        }
        return $this->response->item(compact('token'));
    }

---

我正在用postman进行测试，也遇到了同样的问题，我通过在config文件夹中的auth.php文件中将我的默认保护设置为“web”解决了这个问题

'defaults' => [
    'guard' => 'web',
    'passwords' => 'users',
],

---

请记住，您的路由不应为此登录使用auth中间件，因为这只是为了进行身份验证。

谢谢！！那太有用了！