Using custom Validator in Laravel

validation-en.php

<?php // resources/lang/en/validation.php

return [
    // ...
    'foo' => 'The :attribute must be a valid "foo".',
];

validation-pt.php

<?php // resources/lang/pt/validation.php

return [
    // ...
    'foo' => 'O :attribute deve ser um "foo" válido.',
];

ValidationServiceProvider.php

<?php // app/Providers/ValidationServiceProvider.php

namespace App\Providers;

use App\Validation\Validator;
use Illuminate\Support\ServiceProvider;

class ValidationServiceProvider extends ServiceProvider
{
    public function boot()
    {
        $this->registerCustomValidator();
    }

    public function registerCustomValidator()
    {
        $this->app->validator->resolver(
            function ($translator, $data, $rules, $messages) {
                return new Validator($translator, $data, $rules, $messages);
            }
        );
    }
}

Validator.php

<?php // app/Support/Validation/Validator.php

namespace App\Validation;

use Illuminate\Validation\Validator as BaseValidator;

class Validator extends BaseValidator
{
    protected function validateFoo($attribute, $value)
    {
        // your implementation here
    }
}