1. Not working:

When I try to use a random array element for rotation, proxy is going directly without parent proxies at all, but when I'm copying\pasting any element of "@valid_routes" array into my code and use it directly, everything is going ok, proxy is used for serving requests. In other words:

$cur_proxy$j - it's not working

http://111.111.111.111:12345/ - it's working. This IP was pasted from simple .txt file. As far as I can see this should prove that request is being prepared, authorization on parent proxy is going Ok, and approach used for rotation of UserAgent string may be right. Also I checked @valid_routes, it's filled before each request.

I don't quite know what you're saying -- I cannot relate everything to the code you're posted. For instance, now you're talking about $cur_proxy[$j], as if @cur_proxy is an array, but in your original code, $cur_proxy is a string.

Let me ask it again, can you provide us with a small, standalone piece of code that shows the errorneous behaviour?

 $ua->proxy(['http'], $cur_proxy);

It's here, $cur_proxy should be a string looking like this: http://111.111.111.111:12345/, randomly chosen from array . If I use $cur_proxy, this string is ignored, and traffic goes directly without any proxification. But if I comment out:

 my $cur_proxy = $valid_routes[$j];
 $ua->proxy(['http'], $cur_proxy);
[download]

and rewrite it like this:

 $ua->proxy(['http'], 'http://111.111.111.111:12345/')

traffic goes through a proxy, as it should. So I need to make rotation work, somehow.