Hello,

I am trying to rewrite the User-Agent header using the request_preprepare handler. For testing purposes, I have a webserver set up that redirects / to /dog, /dog to /cat, and /cat to /cat/.

I have the following code: 

use strict;
use warnings;

use LWP::UserAgent;

my $url = "http://127.0.0.1";
my $ctr = 0;

my $ua = LWP::UserAgent->new();
$ua->agent('BOGUS');

$ua->add_handler( request_preprepare => sub { $ua->agent("TEST $ctr");
+ print "User-Agent: ", $ua->agent, "\n"; $ctr++; });

my $response = $ua->get($url);

[download]

Running the above results in the following output:

User-Agent: TEST 0
User-Agent: TEST 1
User-Agent: TEST 2
User-Agent: TEST 3

But the webserver log show the following:

127.0.0.1 - - 12/Aug/2014:23:06:09 -0400 "GET / HTTP/1.1" 302 204 "-" "TEST 0"
127.0.0.1 - - 12/Aug/2014:23:06:09 -0400 "GET /dog HTTP/1.1" 302 204 "-" "TEST 0"
127.0.0.1 - - 12/Aug/2014:23:06:09 -0400 "GET /cat HTTP/1.1" 302 205 "-" "TEST 0"
127.0.0.1 - - 12/Aug/2014:23:06:09 -0400 "GET /cat/ HTTP/1.1" 200 669 "-" "TEST 0"

It sets "TEST 0" as the initial User-Agent for the request for / (correctly replacing "BOGUS"), but it never increments for /dog, /cat, or /cat/ although it appears the handler is being called.

What am I doing wrong?

I can make this work by setting max_redirects to 0 and doing the redirect work manually by creating new LWP::UserAgent objects, but that is less elegant.

Thanks!

In reply to User-Agent in LWP::UserAgent by msel

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