How to find rffer in yii2 when you receive Post request with cUrl from another site?

Question

Yii

How to find rffer in yii2 when you receive Post request with cUrl from another site?
I try so it gives out Null

var_dump(Yii::$app->request->getReferrer());
            die;

Answer 1

It is necessary that the site (which makes the curl request) send such a header