private function addIndexesSection(ArrayNodeDefinition $rootNode)
    {
        $rootNode
            ->fixXmlConfig('index')
            ->children()
                ->arrayNode('indexes')
                    ->useAttributeAsKey('name')
                    ->prototype('array')
                        ->children()
                            ->scalarNode('index_name')
                                ->info('Defaults to the name of the index, but can be modified if the index name is different in ElasticSearch')
                            ->end()
                            ->booleanNode('use_alias')->defaultValue(false)->end()
                            ->scalarNode('client')->end()
                            ->variableNode('settings')->defaultValue(array())->end()
                        ->end()
                    ->end()
                ->end()
            ->end()
        ;
    }