Yii2: ActiveForm: combine rules / multiple validation on one field

Question

LoginForm:

public function rules()
{
    return [
        // username and password are both required
        [['username', 'password'], 'required'],
        // username should be a number and of 8 digits
        [['username'], 'number', 'message'=>'{attribute} must be a number'],
        [['username'], 'string', 'length' => 8],
        // password is validated by validatePassword()
        ['password', 'validatePassword'],
    ];
}

/**
 * Validates the password.
 * This method serves as the inline validation for password.
 *
 * @param string $attribute the attribute currently being validated
 * @param array $params the additional name-value pairs given in the rule
 */
public function validatePassword($attribute, $params)
{
    if (!$this->hasErrors()) {
        $user = $this->getUser();
        if (!$user || !$user->validatePassword($this->password)) {
            $this->addError($attribute, 'Incorrect username or password.');
        }
    }
}

I have set up 2 rules for the same field as you can see above:

[['username'], 'number', 'message'=>'{attribute} must be a number'],
[['username'], 'string', 'length' => 8],

I would like the form to display different error messages for the following 3 scenarios situations:

1. The provided value is neither a number, nor 8 characters (digits).
2. The provided value is a number, but is not of 8 characters (digits).
3. The provided value is not a number, but is of 8 characters (digits).

My question is 2 fold:

A. Is there a way to combine these rules in any standard, Yii2 way.
B. In my previous question I have tried to set up a custom validator (the obvious way to solve this), but it was very simply ignored. The only way I could make it validate was if I added the username field to a scenario. However, once I added password too, it was again ignored. Any reason's for this that you can think of? EDIT: skipOnError = false changed nothing at all in this behaviour.

So please, when you answer, make sure you test it preferably in yii2/advanced; I barely touched the default set up, so it should be easy to test.

EDIT: for clarity, I would like to only allow numbers that are of 8 characters (digits), so they can potentially have a leading 0, eg. 00000001, or 00000000 for that matter. This is why it has to be a numeric string.

Answer 1

The best way to combine rules and display custom error messages for different situations is to create a custom validator. Now if you want that to work on client-side too (it was one of my problems detailed in question B above, thanks to @Beowulfenator for the lead on this), you have to create an actual custom validator class extended from the yii2 native validator class.

Here is an example:

CustomValidator.php

<?php

namespace app\components\validators;

use Yii;
use yii\validators\Validator;

class CustomValidator extends Validator
{
    public function init() {
        parent::init();
    }

    public function validateAttribute($model, $attribute) {
        $model->addError($attribute, $attribute.' message');
    }

    public function clientValidateAttribute($model, $attribute, $view)
    {
return <<<JS
messages.push('$attribute message');
JS;
    }
}

LoginForm.php

<?php
namespace common\models;

use Yii;
use yii\base\Model;
use app\components\validators\CustomValidator;

/**
 * Login form
 */
class LoginForm extends Model
{
    public $username;
    public $password;
    public $custom;

    private $_user;


    /**
     * @inheritdoc
     */
    public function rules()
    {
        return [
            // username and password are both required
            [['username', 'password'], 'required'],
            // username should be a number and of 8 digits
            [['username'], 'number', 'message'=>'{attribute} must be a number'],
            [['username'], 'string', 'length' => 8],
            // password is validated by validatePassword()
            ['password', 'validatePassword'],
            ['custom', CustomValidator::className()],
        ];
    }

    // ...

login.php

<?php

/* @var $this yii\web\View */
/* @var $form yii\bootstrap\ActiveForm */
/* @var $model \common\models\LoginForm */

use yii\helpers\Html;
use yii\bootstrap\ActiveForm;

$this->title = 'Login';
?>
<div class="site-login text-center">
    <h1><?php echo Yii::$app->name; ?></h1>

    <?php $form = ActiveForm::begin([
        'id' => 'login-form',
        'fieldConfig' => ['template' => "{label}\n{input}"],
        'enableClientValidation' => true,
        'validateOnSubmit' => true,
    ]); ?>

    <?= $form->errorSummary($model, ['header'=>'']) ?>

    <div class="row">
        <div class="col-lg-4 col-lg-offset-4">
            <div class="col-lg-10 col-lg-offset-1">

                    <div style="margin-top:40px">
                        <?= $form->field($model, 'username') ?>
                    </div>

                    <div>
                        <?= $form->field($model, 'password')->passwordInput() ?>
                    </div>

                    <div>
                        <?= $form->field($model, 'custom') ?>
                    </div>

                    <div class="form-group" style="margin-top:40px">
                        <?= Html::submitButton('Login', ['class' => 'btn btn-default', 'name' => 'login-button']) ?>
                    </div>

            </div>
        </div>
    </div>

    <?php ActiveForm::end(); ?>

</div>

Answer 2

Finally you need this :

• the value is required
• the value must be a string of 8 chars
• the value must contains only digits

So you should simply try :

['username', 'required'],
['username', 'string', 'min' => 8, 'max' => 8],
['username', 'match', 'pattern' => '/^[0-9]{8}$/', 'message'=>'{attribute} must be a number'],

Answer 3

Yii2 ignores your validation rules may because you duplicated not only attribue but also types. With number validation, i think you should use min/max option to validate number length.

For this case:

'min'=>10000000,'max'=>99999999