Re^3: LWP handlers examples?

After a bit of RTFM-ing, reading the source and experimenting, I think the %matchspec is supposed to be used something like this:

use LWP::UserAgent qw( );

my $ua = LWP::UserAgent->new();
my $url = 'http://www.google.com/';
my $resp;

$resp = $ua->get($url); print($resp->status_line(), "\n");
show(1);
print("Added:\n");
$ua->add_handler( response_header => sub { print "HANDLER\n"; }, owner
+ => "myfunc");
show(2);
$resp = $ua->get($url); print($resp->status_line(), "\n");
show(3);
print("Removed:\n");
$ua->remove_handler('response_header', owner => "myfunc");
show(4);
$resp = $ua->get($url); print($resp->status_line(), "\n");
show(5);

sub show {
  print(join(" ", @_, $ua->handlers('response_header', $resp)), "\n");
}

__END__
200 OK
1 HASH(0x8c2440)
Added:
2 HASH(0x8c2440) HASH(0x93b0e0)
HANDLER
HANDLER
200 OK
3 HASH(0x8c2440) HASH(0x93b0e0)
Removed:
4 HASH(0x8c2440)
200 OK
5 HASH(0x8c2440)
[download]

where "myfunc" is some self-chosen name that you use to identify the callback for removal.

(When you dump the hashes, you can see that the one associated with the internal handler (HASH(0x8c2440)) has owner => 'LWP::UserAgent::parse_head')

As you can see, the internal callback remains intact this way.

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Re^4: LWP handlers examples? by vitoco (Hermit) on Aug 13, 2009 at 18:37 UTC
This code works OK, even if I change it to use Mechanize instead of UserAgent, but does not work inside my original program... `remove_handler()` removes all available handlers, including the internal, ignoring %matchspec. print "Hdl1: ".join(" ",$mech->handlers('response_header', $mech->re +sponse()))."\n"; $mech->add_handler(response_header => \&response, owner => "vitoco") +; print "Hdl2: ".join(" ",$mech->handlers('response_header', $mech->re +sponse()))."\n"; $mech->add_header('If-Modified-Since', time2str($current)) if $curre +nt; my $resp = $mech->get($url, ':content_file' => "$file.tmp"); $mech->delete_header('If-Modified-Since') if $current; $mech->remove_handler('response_header', owner => "vitoco"); print "Hdl3: ".join(" ",$mech->handlers('response_header', $mech->re +sponse()))."\n"; print "Hdl4: ".join(" ",$mech->handlers('response_header', $resp))." +\n"; [download] `Hdl1: HASH(0x1f87dbc) Hdl2: HASH(0x1f87dbc) HASH(0x1f9d174) Hdl3: Hdl4:` [download] I changed de example to use `:content_file`, and stil works, so it is not that. Note that Hdl3 and Hdl4 uses different response objects (or the same, obtained from different ways).	[reply] [d/l] [select]

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Re^4: LWP handlers examples?
by vitoco (Hermit) on Aug 13, 2009 at 18:37 UTC

This code works OK, even if I change it to use Mechanize instead of UserAgent, but does not work inside my original program... remove_handler() removes all available handlers, including the internal, ignoring %matchspec.

  print "Hdl1: ".join(" ",$mech->handlers('response_header', $mech->re
+sponse()))."\n";
  $mech->add_handler(response_header => \&response, owner => "vitoco")
+;
  print "Hdl2: ".join(" ",$mech->handlers('response_header', $mech->re
+sponse()))."\n";
  $mech->add_header('If-Modified-Since', time2str($current)) if $curre
+nt;
  my $resp = $mech->get($url, ':content_file' => "$file.tmp");
  $mech->delete_header('If-Modified-Since') if $current;
  $mech->remove_handler('response_header', owner => "vitoco");
  print "Hdl3: ".join(" ",$mech->handlers('response_header', $mech->re
+sponse()))."\n";
  print "Hdl4: ".join(" ",$mech->handlers('response_header', $resp))."
+\n";
[download]

Hdl1: HASH(0x1f87dbc)
Hdl2: HASH(0x1f87dbc) HASH(0x1f9d174)
Hdl3:
Hdl4:
[download]

I changed de example to use :content_file, and stil works, so it is not that. Note that Hdl3 and Hdl4 uses different response objects (or the same, obtained from different ways).

[reply]
[d/l]
[select]