use Aws\CloudSearch\CloudSearchClient;
use \Config;

public function index()
{
    $cloudSearchClient = CloudSearchClient::factory(Config::get("wdna-aws::cloudsearch"));

    $domainClient = $cloudSearchClient->getDomainClient(
        'catalog-items',
        ['credentials' => Config::get("wdna-aws::cloudsearch")]
    );

    $result = $domainClient->search([
        'query' => 'matchall',
        'queryParser' => 'structured',
        'size' => '100'
    ])->toArray();

    foreach ($result['hits']['hit'] as $hit) {
        $documents[] = [
            'type' => 'delete',
            'id' => $hit['id']
        ];
    }
    $domainClient->uploadDocuments([
        'contentType' => 'application/json',
        'documents' => json_encode($documents)
    ]);
}