How to remove code repetition in Yii2 validators method `when`? - validation

Question

You have to read my previous problem to understand what i'm talking here about(Link to my problem). So it was solved.
But i have a lot of fields in my view that are always filled by current user's value. And it's code repetition when i doing next
[['new_email'], 'unique', 'targetAttribute' => 'email', 'targetClass' => '\common\models\User',
'when' => function ($model, $attribute) {
$this->isNewEmail = false;
if($model->$attribute != User::find()->where(['id' => Yii::$app->user->id])->one()->email) {
$this->isNewEmail = true;
}
return $this->isNewEmail;
},
'message' => 'This email can not be taken.'],
And this
[['first_name'], 'string', 'min' => 4, 'max' => 50,
'when' => function ($model, $attribute) {
$this->isNewFirstName = false;
if($model->$attribute != User::find()->where(['id' => Yii::$app->user->id])->one()->first_name) {
$this->isNewFirstName = true;
}
return $this->isNewFirstName;
},
],
And so on.
What can i do to remove this code repetition. Or is there are somewhere exists module or component for Yii2 just like for this situation like mine? Or is there are somewhere exists core validator for my issue? Or i doomed forever to do all of this code repetition?)

Answer 1

You can see that 2 when callable function have same structure. So you can write a simple function like that:
/**
* #param $model ActiveRecord
* #param $attribute string
* #return bool
*/
public function checkUniqueAttribute($model, $attribute)
{
return $model->$attribute != $model::find()->where(['id' => Yii::$app->user->id])->one()->$attribute;
}
And use it in your rules:
[
['new_email'], 'unique',
'targetAttribute' => 'email',
'targetClass' => '\common\models\User',
'message' => 'This email can not be taken.',
'when' => 'checkUniqueAttribute',
],
[
['first_name'], 'unique',
'targetAttribute' => 'first_name',
'targetClass' => '\common\models\User',
'message' => 'This first name can not be taken.',
'when' => 'checkUniqueAttribute',
],
[['first_name'], 'string', 'min' => 4, 'max' => 50,],
Hope it useful.
Goodluck and have fun!