src/ElasticSearch/Client.php
public function beginBulk() {
        if (!$this->bulk) {
            $this->bulk = $this->createBulk($this);
        }
        return $this->bulk;
    }
public function beginBulk() {
        if (!$this->bulk) {
            $this->bulk = $this->createBulk($this);
        }
        return $this->bulk;
    }
Begin a transparent bulk-transaction
if one is already running, return its handle
@return \Elasticsearch\Bulk