Webiny\Component\Amazon\S3::getListObjectsIterator PHP Method

    public function getListObjectsIterator($bucket, array $params = [])
    {
        return $this->instance->getListObjectsIterator($bucket, $params);
    }

 /**
  * @inheritdoc
  */
 public function getKeys($key = '', $recursive = false)
 {
     $s3Data = ['Prefix' => $key];
     $iterator = $this->s3Client->getListObjectsIterator($this->bucket, $s3Data);
     $files = [];
     foreach ($iterator as $file) {
         $files[] = $file['Key'];
     }
     return $files;
 }