HttpClient::setProxy

public function setProxy($proxyHost, $proxyPort = null, $proxyUser = null, $proxyPassword = null)
{
	$this->proxyHost = $proxyHost;
	$proxyPort = (int)$proxyPort;
	if ($proxyPort > 0)
	{
		$this->proxyPort = $proxyPort;
	}
	$this->proxyUser = $proxyUser ?? '';
	$this->proxyPassword = $proxyPassword ?? '';

	return $this;
}