private function createElasticClient($clientName, ContainerBuilder $container)
    {
        // Storage metadata
        $smfName = sprintf('%s.metadata', $clientName);
        $definition = new Definition(
            Utility::getLibraryClass('Search\Elastic\StorageMetadataFactory')
        );
        $definition->setPublic(false);
        $container->setDefinition($smfName, $definition);

        // Client
        return new Definition(
            Utility::getLibraryClass('Search\Elastic\Client'),
            [new Reference($smfName)]
        );
    }