public function __construct($accessKeyId, $secretAccessKey, $region, $endpoint = null)
{
$settings = ['region' => $region, 'signature' => 'v4', 'version' => '2006-03-01', 'credentials' => ['key' => $accessKeyId, 'secret' => $secretAccessKey]];
if (!empty($endpoint)) {
$settings['endpoint'] = $endpoint;
}
$this->instance = S3Client::factory($settings);
}