title: Symfony2 Group permissions with ACL
body: <p>Where I work we are designing a webapp in which <strong>users</strong> may belong to <strong>multiple groups</strong> and each group has access on a set of resources not known in advanced. Plus, users can enter or leave groups and groups can acquire or lose access to resources, so the whole permission granting system needs to be dynamic.</p>
  
  <p>We are using Symfony2 and the FOSUserBundle.</p>
  
  <p>We like how the ACL system works, but we could not find a way to apply it to the Group object.</p>
  
  <p>Has anyone done something like that with Symfony? Or do you have any suggestion on how to implement it in other ways?</p>