How can I screen scrape with Perl?

Question

I need to display some values that are stored in a website, for that I need to scrape the website and fetch the content from the table. Any ideas?

Answer 1

If you are familiar with jQuery you might want to check out pQuery, which makes this very easy:

## print every <h2> tag in page
use pQuery;

pQuery("http://google.com/search?q=pquery")
    ->find("h2")
    ->each(sub {
        my $i = shift;
        print $i + 1, ") ", pQuery($_)->text, "\n";
    });

There's also HTML::DOM.

Whatever you do, though, don't use regular expressions for this.

Answer 2

I have used HTML Table Extract in the past. I personally find it a bit clumsy to use, but maybe I did not understand the object model well. I usually use this part of the manual to examine the data:

 use HTML::TableExtract;
 $te = HTML::TableExtract->new();
 $te->parse($html_string);

     # Examine all matching tables
     foreach $ts ($te->tables) {
       print "Table (", join(',', $ts->coords), "):\n";
       foreach $row ($ts->rows) {
          print join(',', @$row), "\n";
       }
     }`

Answer 3

I use LWP::UserAgent for most of my screen scraping needs. You can also Couple that with HTTP::Cookies if you need Cookies support.

Here's a simple example on how to get source.

use LWP;
use HTTP::Cookies;
my $cookie_jar = HTTP::Cookies->new;
my $browser = LWP::UserAgent->new;
$browser->cookie_jar($cookie_jar);

$resp = $browser->get("https://www.stackoverflow.com");
if($resp->is_success) {
   # Play with your source here
   $source = $resp->content;
   $source =~ s/^.*<table>/<table>/i; # this is just an example 
   print $source;                     # not a solution to your problem.
}

Answer 4

Although I've generally done this with LWP/LWP::Simple, the current 'preferred' module for any sort of webpage scraping in Perl is WWW::Mechanize.

Answer 5

If you're familiar with XPath, you can also use HTML::TreeBuilder::XPath. And if you're not... well you should be ;--)

Answer 6

For similar Stackoverflow questions have a look at....

• How can I extract URLs from a web page in Perl
• How can I extract XML of a website and save in a file using Perl’s LWP?

I do like using pQuery for things like this however Web::Scraper does look interesting.

/I3az/

Answer 7

I don't mean to drag up a dead thread but anyone googling across this thread should also checkout WWW::Scripter - 'For scripting web sites that have scripts'

happy remote data aggregating ;)

Answer 8

Take a look at the magical Web::Scraper, it's THE tool for web scraping.

Answer 9

Check out this little example of web scraping with perl: link text