Content acces basing on a field value

Question

In Drupal 8, how do I give access to some nodes to users with specific roles, depending on a field value or a taxonomy value?

Answer 1

this is how i did it ( simplified for demo purpose )

function my_module_node_access(NodeInterface $node, $op, AccountInterface $account) {

global $user;
$user = \Drupal\user\Entity\User::load($account->id());

  if ($node->bundle() == 'my_content_type') {
    if ($op == 'view') {
        $visibility=$node->field_visibilite->getString();
        $target=$node->field_target->getString();


        if ($visibility ==='all')
            return \Drupal\Core\Access\AccessResult::allowed();

        if ($visibility ==='restricted') 
            if (($target === 'group1') && ($user->hasRole('group1')))
                return \Drupal\Core\Access\AccessResult::allowed();


}

 return \Drupal\Core\Access\AccessResult::forbidden();

}