Sonata\DeliveryBundle\DependencyInjection\Configuration::getConfigTreeBuilder PHP Method

    public function getConfigTreeBuilder()
    {
        $treeBuilder = new TreeBuilder();
        $node = $treeBuilder->root('sonata_delivery');
        $node->children()->scalarNode('selector')->defaultValue('sonata.delivery.selector.default')->cannotBeEmpty()->end()->end();
        $this->addDeliverySection($node);
        $this->addModelSection($node);
        return $treeBuilder;
    }