public function createClient()
{
if ($this->client === null) {
$clientBuilder = ClientBuilder::create();
$hosts = $this->getHosts();
$clientBuilder->setHosts($hosts);
if ($this->clientConfiguration->isDebugModeEnabled()) {
$clientBuilder->setLogger($this->logger);
}
$this->client = $clientBuilder->build();
}
return $this->client;
}