public function getClient()
	{
		if ($this->_client === null) {
			$settings=[
				'key' => $this->key,
				'secret' => $this->secret
			];
			if($this->enableV4)
				$settings['signature']='v4';
			
			$this->_client = S3Client::factory($settings);
		}
		return $this->_client;
	}