Perl in a Nutshell, 2nd Edition

URI

The URI module is a successor to URI::URL and was written by Gisle Aas. While not clearly stated in the LWP documentation, you should use the URI module whenever possible, since URI.pm has essentially deprecated URI::URL.

The URI module implements the URI class. Objects created from the URI class represent Uniform Resource Identifiers (URIs). With the URI module, you can identify the key parts of a URI: scheme, scheme-specific parts, and fragment identifiers, which may be referred to respectfully as authority, path, and query components. For example, as shown in the URI module documentation:

<scheme>:<scheme-specific-part>#<fragment>
<scheme>://<authority><path>?<query>#<fragment>
<path>?<query>#<fragment>

You can break down http://www.oreilly.com/somefile.html as:

scheme: http
authority: www.oreilly.com
path: /somefile.html

In the case of relative URIs, you can use the URI module to deal with only the query component of a URI. With the URI module, you can parse the above URI as follows:

#!/usr/local/bin/perl -w

use URI;

my $url = 'http://www.oreilly.com/somefile.html';
my $u1 = URI->new($url);

print "scheme: ", $u1->scheme, "\n";
print "authority: ", $u1->authority, "\n";
print "path: ", $u1->path, "\n";