3

I have a rule (foobar) that is not built in to Laravel that I want to use within my extended FormRequest. How can I create a custom validator for that specific rule?

public function rules() {
    return [
        'id' => ['required', 'foobar']
    ];
}

I know Validator::extend exists but I don't want to use facades. I want it "built in" to my FormRequest. How do I do that and is it even possible?

Marwelln
  • 28,492
  • 21
  • 93
  • 117

2 Answers2

6

It is possible to have your custom validation method by creating a validator property to your class and setting it to app('validator'). You can then with that property run extend, just like with the facade.

Create a __construct method and add this:

public function __construct() {
    $this->validator = app('validator');

    $this->validateFoobar($this->validator);
}

Then create a new method called validateFoobar that take the validator property as the first argument and run extend on that, just like with the facade.

public function validateFoobar($validator) {
    $validator->extend('foobar', function($attribute, $value, $parameters) {
        return ! MyModel::where('foobar', $value)->exists();
    });
}

More detail about extend is available here.

In the end, your FormRequest could look like this:

<?php namespace App\Http\Requests;

use App\Models\MyModel;
use App\Illuminate\Foundation\Http\FormRequest;

class MyFormRequest extends FormRequest {
    public function __construct() {
        $this->validator = app('validator');

        $this->validateFoobar($this->validator);
    }

    public function rules() {
        return [
            'id' => ['required', 'foobar']
        ];
    }

    public function messages() {
        return [
            'id.required' => 'You have to have an ID.',
            'id.foobar' => 'You have to set the foobar value.'
        ];
    }

    public function authorize() { return true; }

    public function validateFoobar($validator) {
        $validator->extend('foobar', function($attribute, $value, $parameters) {
            return ! MyModel::where('category_id', $value)->exists();
        });
    }
}
Marwelln
  • 28,492
  • 21
  • 93
  • 117
  • How would you do this and also make a custom error message for the new validation filter? – Jim Rubenstein Feb 16 '15 at 17:20
  • 1
    @JimRubenstein: You can put custom messages in `/resources/lang/de/validation.php` like this: ` [ 'id' => [ 'foobar' => 'Custom Message', ], ], ];` – roNn23 Feb 18 '15 at 20:37
  • 1
    @JimRubenstein, you can use the [messages](https://github.com/laravel/framework/blob/5.0/src/Illuminate/Foundation/Http/FormRequest.php#L213) method in your FormRequest. See my updated answer for an example. – Marwelln Feb 18 '15 at 21:02
  • 1
    @Marwelln after some research, there's also an undocumented 3rd parameter to `Validator::extend` that accepts the error message. I like the `FormRequest::messages` approach better, though! @roNn23 I knew about the language files - that's more abstraction than I need at the moment though. Thanks! – Jim Rubenstein Feb 19 '15 at 14:55
1

From version 5.4 you can use the withValidator method to extend the rule.

<?php namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;

class MyFormRequest extends FormRequest
{

    public function rules() {
        return [
            'id' => ['required', 'foobar']
        ];
    }

    public function messages() {
        return [
            'id.required' => 'You have to have an ID.',
            'id.foobar' => 'You have to set the foobar value.'
        ];
    }

    public function withValidator($validator)
    {
        $validator->addExtension('foobar', function ($attribute, $value, $parameters, $validator) {
            return ! MyModel::where('category_id', $value)->exists();
        });
    }
}
ibpavlov
  • 106
  • 3