Symfony 3 - Cannot use session get user - php

Question

I have a User entity on my project.
Each page load, I bother to recover the user with a query in the database.
My goal is to put it in session variable directly after it has logged in to simply get it back when I want.
In my code, if I test this:
$user = $this->checkBDD($mail,$fredurne,$nomComplet);
dump($user);
$this->session->set('user',$user);
$user = $this->session->get('user');
dump($user);
I have :
So, the session seems work.
Now, I put it into application. I create a function:
$user = $this->getUtilisateur($mail,$fredurne,$nomComplet);
dump($user);
With
public function getUtilisateur($mail,$fredurne,$nomComplet)
{
if(!$this->session->has('user'))
{
dump("user not in session");
$user = $this->checkBDD($mail,$fredurne,$nomComplet);
$this->session->set('user',$user);
}
else
{
dump("user in session");
$user = $this->session->get('user');
}
return $user;
}
And I have :
So, I don't understand what's the problem

Answer 1

Problem :
Doctrine entity is stored on session but needs to be refreshed
But when you retrieve the entity from session : Doctrine unit of work does not know it have to handle this entity
After that you should have some issues with Doctrine lazy loading.
Session is not good to store an entity.
A better solution is :
Inject Doctrine entity manager in your service
Only store id on session
On getUtilisateur method retrieve the user with id if not already done