Laravel 5 中自定义的validation放在什么位置比较好？

Laravel 5 中自定义的validation放在什么位置比较好？
最近在论坛发现了个比较满意的方案。

# app/wherever-you-want/CustomValidator.php

<?php

class CustomValidator extends Illuminate\Validation\Validator {

    public function validateFoo($attribute, $value, $parameters)
    {
        return $value == 'foo';
    }

}

<?php

class AppServiceProvider extends ServiceProvider{

  public function boot()
  {
    // ...
    Validator::resolver(function($translator, $data, $rules, $messages)
    {
      return new CustomValidator($translator, $data, $rules, $messages);
    });
    // ...
  }

}

References

l5-where-to-add-custom-validation-function @pmall