To set up proxy settings use useProxy method:
$bot->getHttpClient()->useProxy('192.168.1.1', '12345');
By default it uses http proxy without authentication. If your proxy requires authentication, pass auth string as the third parameter:
$bot->getHttpClient()->useProxy('192.168.1.1', '12345', 'username:password');
Use socks proxy:
$bot->getHttpClient()->useSocksProxy('192.168.1.1', '12345');
// With authentication
$bot->getHttpClient()->useSocksProxy('192.168.1.1', '12345', 'username:password');
If you need to stop sending requests via proxy:
$bot->getHttpClient()->dontUseProxy();
Check if bot uses proxy:
if($bot->getHttpClient()->usesProxy()) {
// ...
}