protected function getResolverRegistry() {
$registry->addFieldResolver('Query', 'menu',
$builder->produce('entity_load')
->map('type', $builder->fromValue('menu'))
->map('id', $builder->fromArgument('name'))
$registry->addFieldResolver('Menu', 'name',
$builder->produce('property_path')
->map('type', $builder->fromValue('entity:menu'))
->map('value', $builder->fromParent())
->map('path', $builder->fromValue('label'))
$registry->addFieldResolver('Menu', 'items',
$builder->produce('menu_links')
->map('menu', $builder->fromParent())
$registry->addFieldResolver('MenuItem', 'title',
$builder->produce('menu_link_label')
->map('link', $builder->produce('menu_tree_link')
->map('element', $builder->fromParent()))
$registry->addFieldResolver('MenuItem', 'children',
$builder->produce('menu_tree_subtree')
->map('element', $builder->fromParent())
$registry->addFieldResolver('MenuItem', 'url',
$builder->produce('menu_link_url')
->map('link', $builder->produce('menu_tree_link')
->map('element', $builder->fromParent()))
$registry->addFieldResolver('Url', 'path',
$builder->produce('url_path')
->map('url', $builder->fromParent())