I'm trying to write a link parser that takes a URL and returns an array of links on the page that are within in the /attachments sub tree of a Web server's document tree. The subroutine parse_page works fine if it is only called one time. Subsequent invocations of the subroutine within the same program return nothing in the array, although I am sure that there are links that meet the criteria.

What I want to do is set up a main subroutine which grabs URLs from a database table, passes them one at a time to parse_page, and receives back a corresponding array of links. And to be perfectly clear, I want to do this serially.

I'm sorry if I have done something stupid. I have been sick all week, and I am working on less than my normal powers of abstract reasoning and concentration. I shamelessly leveraged the example code in the perldoc for HTML::LinkExtor and squinted at the screen for a while to get this far.

Dave Aiello
Chatham Township Data Corporation 

#!/usr/local/bin/perl

use LWP::UserAgent;
use HTML::LinkExtor;
use URI::URL;


sub parse_page
{


    my($url) = @_;

    my $ua = LWP::UserAgent->new;

    my @links = ();


    sub attachment_link_extractor
    {
        my ($tag, %attr) = @_;

        push(@links, values %attr)
            if (($tag eq 'a') &&
                ($attr{href} =~ m/attachments/));
    }

    my $p = HTML::LinkExtor->new(\&attachment_link_extractor);

    $res = $ua->request(HTTP::Request->new(GET => $url),
                sub {$p->parse($_[0])});

    my $base = $res->base;

    @links = map
        {
            if ($_ =~ /^http/)
            {
                $_ = "/". url($_, $base)->rel;
            }
            else
            {
                $_ = $_;
            }
        } @links;

    $p->links;

    return(@links);

}

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In reply to Why is this link parser only working the first time? by dave_aiello

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