trusty (3) Web::Scraper.3pm.gz

NAME

       Web::Scraper - Web Scraping Toolkit using HTML and CSS Selectors or XPath expressions

SYNOPSIS

         use URI;
         use Web::Scraper;

         # First, create your scraper block
         my $tweets = scraper {
             # Parse all LIs with the class "status", store them into a resulting
             # array 'tweets'.  We embed another scraper for each tweet.
             process "li.status", "tweets[]" => scraper {
                 # And, in that array, pull in the elementy with the class
                 # "entry-content", "entry-date" and the link
                 process ".entry-content", body => 'TEXT';
                 process ".entry-date", when => 'TEXT';
                 process 'a[rel="bookmark"]', link => '@href';
             };
         };

         my $res = $tweets->scrape( URI->new("http://twitter.com/miyagawa") );

         # The result has the populated tweets array
         for my $tweet (@{$res->{tweets}}) {
             print "$tweet->{body} $tweet->{when} (link: $tweet->{link})\n";
         }

       The structure would resemble this (visually)
         {
           tweets => [
             { body => $body, when => $date, link => $uri },
             { body => $body, when => $date, link => $uri },
           ]
         }

DESCRIPTION

       Web::Scraper is a web scraper toolkit, inspired by Ruby's equivalent Scrapi. It provides a DSL-ish
       interface for traversing HTML documents and returning a neatly arranged Perl data strcuture.

       The scraper and process blocks provide a method to define what segments of a document to extract.  It
       understands HTML and CSS Selectors as well as XPath expressions.

METHODS

   scraper
         $scraper = scraper { ... };

       Creates a new Web::Scraper object by wrapping the DSL code that will be fired when scrape method is
       called.

   scrape
         $res = $scraper->scrape(URI->new($uri));
         $res = $scraper->scrape($html_content);
         $res = $scraper->scrape(\$html_content);
         $res = $scraper->scrape($http_response);
         $res = $scraper->scrape($html_element);

       Retrieves the HTML from URI, HTTP::Response, HTML::Tree or text strings and creates a DOM object, then
       fires the callback scraper code to retrieve the data structure.

       If you pass URI or HTTP::Response object, Web::Scraper will automatically guesses the encoding of the
       content by looking at Content-Type headers and META tags. Otherwise you need to decode the HTML to
       Unicode before passing it to scrape method.

       You can optionally pass the base URL when you pass the HTML content as a string instead of URI or
       HTTP::Response.

         $res = $scraper->scrape($html_content, "http://example.com/foo");

       This way Web::Scraper can resolve the relative links found in the document.

   process
         scraper {
             process "tag.class", key => 'TEXT';
             process '//tag[contains(@foo, "bar")]', key2 => '@attr';
             process '//comment()', 'comments[]' => 'TEXT';
         };

       process is the method to find matching elements from HTML with CSS selector or XPath expression, then
       extract text or attributes into the result stash.

       If the first argument begins with "//" or "id(" it's treated as an XPath expression and otherwise CSS
       selector.

         # <span class="date">2008/12/21</span>
         # date => "2008/12/21"
         process ".date", date => 'TEXT';

         # <div class="body"><a href="http://example.com/">foo</a></div>
         # link => URI->new("http://example.com/")
         process ".body > a", link => '@href';

         # <div class="body"><!-- HTML Comment here --><a href="http://example.com/">foo</a></div>
         # comment => " HTML Comment here "
         #
         # NOTES: A comment nodes are accessed when installed
         # the HTML::TreeBuilder::XPath (version >= 0.14) and/or
         # the HTML::TreeBuilder::LibXML (version >= 0.13)
         process "//div[contains(@class, 'body')]/comment()", comment => 'TEXT';

         # <div class="body"><a href="http://example.com/">foo</a></div>
         # link => URI->new("http://example.com/"), text => "foo"
         process ".body > a", link => '@href', text => 'TEXT';

         # <ul><li>foo</li><li>bar</li></ul>
         # list => [ "foo", "bar" ]
         process "li", "list[]" => "TEXT";

         # <ul><li id="1">foo</li><li id="2">bar</li></ul>
         # list => [ { id => "1", text => "foo" }, { id => "2", text => "bar" } ];
         process "li", "list[]" => { id => '@id', text => "TEXT" };

EXAMPLES

       There are many examples in the "eg/" dir packaged in this distribution.  It is recommended to look
       through these.

NESTED SCRAPERS

       TBD

FILTERS

       TBD

AUTHOR

       Tatsuhiko Miyagawa <miyagawa@bulknews.net>

LICENSE

       This library is free software; you can redistribute it and/or modify it under the same terms as Perl
       itself.

SEE ALSO

       <http://blog.labnotes.org/category/scrapi/>

       HTML::TreeBuilder::XPath