(jeffa) Re: Lack of LWP::SIMPLE information

There are (IIRC) two ways to redirect ... one is to use a Redirection Header and the other is to use a <meta> tag:

<meta http-equiv="Refresh" content="15; URL=redirect.html"/>

I set up two (three including the file redirected to) test files:

redirect.html:

<html>
<meta http-equiv="Refresh" content="1; URL=redirected.html"/>
<head>
<title>redirect</title>
</head>
<body>
you won't see me
</body>
</html>
[download]

cgi-bin/redirect.cgi:

#!/usr/bin/perl -Tw

use strict;
use CGI qw(redirect);

print redirect('http://localhost/redirected.html');
[download]

And then i fetched both pages with LWP::Simple. Here are the results:

[jeffa]$ perl -MLWP::Simple -le'getprint "http://localhost/cgi-bin/red
+irect.cgi"'
<html>
<head>
<title>redirected!</title>
</head>
<body>
you've been redirected!
</body>
</html>

[jeffa]$ perl -MLWP::Simple -le'getprint "http://localhost/redirect.ht
+ml"'
<html>
<meta http-equiv="Refresh" content="1; URL=redirected.html"/>
<head>
<title>redirect</title>
</head>
<body>
you won't see me
</body>
</html>
[download]

So ... in semi-conclusion, looks like LWP::Simple will transparantly grab the redirected page IF the redirection was implemented with a redirection header, not a meta tag. Hope this helps.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

Comment on (jeffa) Re: Lack of LWP::SIMPLE information Select or Download Code

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Re: (jeffa) Re: Lack of LWP::SIMPLE information by Dog and Pony (Priest) on Jul 17, 2003 at 21:19 UTC
LWP::UserAgent (which LWP::Simple uses) follows redirects by default for GET and HEAD requests - this is a configurable behaviour, see `requests_redirectable` and `redirect_ok` in the documentation. It also stands to reason that only header redirects (ie `Status: 302 Moved`) is followed. Otherwise the module would need to parse the HTML looking for meta tags. Using the proper modules, or maybe just a simple regexp, this is not too hard to implement yourself, but it doesn't belong in the core module IMO. :) Another way that some (thankfully few nowadays) do redirects is by scripting, such as javascript. This is a tougher nut to crack if needed. You have moved into a dark place. It is pitch black. You are likely to be eaten by a grue.	[reply] [d/l] [select]
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