Yii2 - How to modify controller action param using a behavior? - yii2

Question

I'm trying to change the $id param in my controller methods on the fly using beforeAction and a behavior. FYI, I'm going to use HashIds and need to convert anywhere I have a $_GET['id'] that may be hashed back into an integer.
How can I use a behavior to automatically modify my $_GET['id'] on the fly using a behavior?
An example action in my controller:
public function actionView($id){
// run code to process $id here back to integer using a behavior
echo $id; //should be an integer
}
My sample url: http://mydomain/posts/view?id=3QhLp
(Alternatively, perhaps the better way to do this is to create a custom url rule?)

Answer 1

you should implement a class that extends from the \yii\base\Behavior like below
<?php
namespace backend\models;
use Yii;
use yii\base\Behavior;
use yii\web\Controller;
class Transformer extends Behavior
{
public $id = '';
public function events()
{
return [Controller::EVENT_BEFORE_ACTION => 'transform']; //mounting the handler to the 'beforeAction' event on the controller.
}
public function transform()
{
$_GET['id'] = $this->id . "transformed"; //mock method here
return true;
}
}
Then in your controller, adding the code as follow:
public function behaviors()
{
return [
'transformer' => [
'class' => \backend\models\Transformer::className(), //Modify the path to your real behavior class.
'id' => Yii::$app->request->get('id'),
],
];
}
then access the Yii::$app->request->get('id') in your action, you will see the transformed url param.