Hi! I'm writing a web application and I'd like to add proxy support in case the user wants anonymity or has to use a proxy to access the web.

LWP::UserAgent claims to support proxies, but I've had limited success. I can go through one proxy without problems: 

use LWP::UserAgent;

$ua = LWP::UserAgent->new;

$ua->proxy("http", "http://proxy_host:proxy_port/");
    
my $req = HTTP::Request->new(GET => "http://www.google.com/");
my $res = $ua->request($req);

if ($res->is_success) {
    print $res->content;
} else {
     print "Bad luck this time\n";
}

[download]
But how can I chain multiple proxies? I've tried: 
$ua->proxy("http", "http://proxy1_host:proxy1_port/ http://proxy2_host
+:proxy2_port/");

$ua->proxy("http", "http://proxy1_host:proxy1_port/"); 
$ua->proxy("http", "http://proxy2_host:proxy2_port/");

[download]
The later only uses proxy2 and the former only uses proxy1!

In Internet Explorer, I can easily use multiple proxies using a syntax similar to my first attempt, so it seems that is the standard method of chaining proxies. Am I missing something obvious? How can LWP::UserAgent be told to chain proxies?

Should I use another module? I looked on CPAN and at the HTTP::Lite docs, but it from what I gather, this module only supports a single proxy too.

I'd really like to have proxy chaining support; do no Perl modules support it? Shall I roll my own HTTP implementation??

In reply to Chaining proxies with LWP::UserAgent by Anonymous Monk

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