Newscoop\Entity\User::getRoles PHP Method

    public function getRoles()
    {
        $roles = array();
        foreach ($this->groups as $group) {
            $roles[] = strtoupper(str_replace(" ", "_", $group->getName()));
        }
        return $roles;
    }

 /**
  * Log in user
  *
  * @param Newscoop\Entity\User $user
  * @param string               $providerKey
  *
  * @return UsernamePasswordToken
  */
 public function loginUser(User $user, $providerKey)
 {
     $roles = $user->getRoles();
     $token = new UsernamePasswordToken($user, null, $providerKey, $roles);
     $this->security->setToken($token);
     return $token;
 }