Yii2 rules compareAttribute compare with attribute of another model

Question

during validation I would like to compare with an attribute from another model. Is it possible? If yes, I would be grateful if you would point me to the right direction. I imagine it somehow to access model B in model A, but maybe my logic is not good, and I have no clue how can this be achieved. Thanks.

Answer 1

I've solved it this way:

public function getRelatedmodel() {
    return $this->hasOne(\app\models\Relatedmodel::className(), ['id' => 'relatedId']);
}

public function getMotherRelatedAttribute() {
    if ($mother = Model::findOne($this->mother)) {
        return $mother->relatedmodel->attribute;
    }
}

And in rules:

['attribute', 'compare', 'compareAttribute' => 'MotherRelatedAttribute', 'operator' => '<=', 'on' => self::SCENARIO_CREATE_RST],