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Need Perl program to parse amazon book page

Can anyone of you leet hax0rs hack up a Perl program that can parse an Amazon book page and notify me when a used book is less than a certain amount? I could run it through the Windows scheduler to check every 5 minutes and it would help a lot.
I get paid to do that. You can lookup WWW::Mechanize or LWP and do it yourself, though.

In fact, if you can show me the chunk of HTML the price on your page is in and the url, I can probably do it in shell with grep as a one-liner. That I could do for you.

but PHP is so much easier than LWP

and why use grep when you can use ack, it’s 25% more efficient with it’s lack of 1 letter
Ahh I never thought about just using grep… I’m on Windows XP so what would you recommend I use to download the page?

Here is the part of the page I need to match on..

used & new</a> available from <span class="price">$53.96</span><br />
I saw that. And PHP is not so much easier than LWP. PHP is much harder than LWP. With LWP you do this:

wget url

Real hard, right?

OP: Download and install LWP’s wget program, and ActivePerl and I will do it for you.
Thanks man, I think I already have LWP installed. When I type:

perl -MLWP -le "print(LWP->VERSION)"

I get 5.803
Ok, are the utilities installed? Does the command line: wget work?

I guess they’re not a part of LWP no more.
Alright, I’ve got LWP v5.803, wget.exe v1.10.2, and Perl v5.8.7
Where are you man? Don’t give up on meh!

Please respond.

Thanks!
I can’t believe I did this for you. I should have used an html parser, or whipped up an elite one liner, but wtf this works:

#!/usr/bin/perl

use warnings;
use strict;

use LWP;

# Get args – url and price
my $price_limit = $ARGV[0]||die "Must supply price!";
my $url = $ARGV[1]||die "Must supply url!";

# Create a user agent object
use LWP::UserAgent;
my $ua = LWP::UserAgent->new;
$ua->agent("MyApp/0.1 ");

# Create a request
my $req = HTTP::Request->new(GET => $url);

# Pass request to the user agent and get a response back
my $res = $ua->request($req);

# Check the outcome of the response
if ($res->is_success)
{
# Grab content and pull out price
my $content = $res->content;

# If we got our price entry…
if($content =~ /class="priceLarge">$d+.d+/)
{
my @lines = split(/n/, $content);

my $price;
map {

if($_ =~ /class="priceLarge">$d+.d+/)
{
$price = $_;
$price =~ s/.*class="priceLarge">$(d+.d+).*/$1/;

# We got our price, and its less than our limit. Notify chode.
if($price < $price_limit)
{
print "nFor url $url found a price of $$price which is $" . ($price_limit – $price) . " less than our limit of $$price_limit.nn";
exit;
}
}

} @lines;

}
else
{
die "No price found at $urln";
}
}
else
{
print "Problem retrieving page: " . $res->status_line, "n";
}

what happened to that grep one-liner

P.S. I told you that php would be easier than Perl LWP.

It works! I’ve been needing something like this for a while now, thanks!

And no, I can promise you this wasn’t homework.

It works! I’ve been needing something like this for a while now, thanks!

And no, I can promise you this wasn’t homework.

Buy me a subscription to OT.

<?
     # usage: grab.php [link] [price]
     preg_match('#class="priceLarge">$(d+.d+)#',file_get_contents($argv[1]),$m);
     if($m[1]<$argv[2]) echo "nFor url {$argv[1]} found a price of ${$m[1]} which is $".($argv[2] - $m[1])." less than our limit of ${$argv[2]}nn";
?>

I’m broke man, I don’t even have a sub… but I appreciate your help.

<?
     # usage: grab.php [link] [price]
     preg_match('#class="priceLarge">$(d+.d+)#',file_get_contents($argv[1]),$m);
     if($m[1]<$argv[2]) echo "nFor url {$argv[1]} found a price of ${$m[1]} which is $".($argv[2] - $m[1])." less than our limit of ${$argv[2]}nn";
?>

Your skills are impressive, but I wanted it in perl… BTW have you seen your boy Fred Durst lately?

<?
     # usage: grab.php [link] [price]
     preg_match('#class="priceLarge">$(d+.d+)#',file_get_contents($argv[1]),$m);
     if($m[1]<$argv[2]) echo "nFor url {$argv[1]} found a price of ${$m[1]} which is $".($argv[2] - $m[1])." less than our limit of ${$argv[2]}nn";
?>

I handled errors bro. You didn’t.

even if i handled errors it’d still be like 1/4 the size of all that perl code. i’m not trying to brag about skills, just showing that when it comes to anything web related PHP has the upperhand on Perl. PHP was designed for the web whereas Perl was not.

My first Job at 16 was as a data miner programming in Perl and later i started doing Perl/CGI, but PHP is definitely more robust when it comes to the web. I still use Perl for most of my local scripting but when it comes to web stuff, PHP is great.

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