Symfony users providers : FOS + SSO with metadata
<p>I've made a multisite app with classic FOSUserBundle provider.
Each user is linked to a site by a ManyToOne relation between User and Site entity.</p>

<p>My point : I'm asked now to setup a SSO system on a per-site basis. Although it seems pretty clear that I can mix providers for authentication (and then having FOS + SSO), <strong>how can I handle possible metadata linked to user cleared by SSO, such as site belonging information?</strong> </p>

<ul>
<li>Should I create a user copy when cleared by SSO on my system (and then "break" SSO logic)? </li>
<li>Should I have to add this data on my User entity on-the-fly after SSO clearance?</li>
</ul>

<p>Thank you for your answers,</p>

<p>Regards,</p>