Scrappy::Scraper::Parser(3) Scrappy Scraper Data Extrator

VERSION

version 0.94112090

SYNOPSIS


#!/usr/bin/perl
use Scrappy::Scraper::Parser;
my $parser = Scrappy::Scraper::Parser->new;
$parser->html($html);

# get all links in all table rows with CSS selector
my $links = $parser->scrape('table tr a');

# select all links in the 2nd table row of all tables with XPATH selector
my $links = $parser->scrape('//table/tr[2]/a');

# percision scraping !
# select all links in the 2nd table row ONLY with CSS selectors and focus()
my $links =
$parser->select('table tr')
->focus(2)
->scrape('a');

DESCRIPTION

Scrappy::Scraper::Parser provides various tools for scraping/extracting information from web pages using the Scrappy framework.

ATTRIBUTES

The following is a list of object attributes available with every Scrappy::Scraper::Parser instance.

data

The data attribute gets/sets the extracted data which is returned from the scrape method.

    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->select('table tr');
        $parser->data;

html

The html attribute gets/sets the HTML content to be parsed and extracted from.

    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->html($HTML);

html_tags

The html_tags attribute gets a hashref of all known HTML tags and attributes to be used with Web::Scraper.

    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->html_tags;

worker

The worker attribute holds the Web::Scraper object which is used to parse HTML and extract data.

    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->worker;

METHODS

filter

The filter method allows you to filter the tags returned within the results by supplying the filter method with a list of tag attributes that you specifically want to return, forsaking all others, including the special text and html tags/keys.

    # filter results and only return meta tags with a content attribute
    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->select('meta');
        print $parser->data;
        
        ...
        
        {
            name => '...',
            text => '...',
            html => '...',
            content => '....',
            http => '...',
            ....
        }
        
        print $parser->filter('name', 'content')->data;
        
        ...
        
        {
            name => '...',
            content => '....',
        }

focus

The focus method is used zero-in on specific blocks of HTML so the selectors only extract data from within the highlighted block. The focus method is meant to be used after the select method extracts rows of data, the focus method is passed an array index which zeros-in on that row of data.

    my  $parser = Scrappy::Scraper::Parser->new;
    
    # percision scraping !
    # select all links in the 2nd table row ONLY
    my  $links = 
        $parser->select('table tr')
           ->focus(2)
           ->scrape('a');

scrape

The scrape method is used to extract data from the specified HTML and return the extracted data. This method is dentical to the select method with the exception of what is returned.

    my  $parser = Scrappy::Scraper::Parser->new;
    my  $links = $parser->scrape('a', $from_html); #get all links

select

The select method is used to extract data from the specified HTML and return the parser object. The data method can be used to access the extracted information.

    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->select('a', $from_html); #get all links
        
    my  $links = $parser->data;

first

The first method is used to return the first element from the extracted dataset.

    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->select('a', $from_html); #get all links
        
    my  $first_link = $parser->first;
    
    # equivalent to ...
    my  $first_link = $parser->data->[0];

last

The last method is used to return the last element from the extracted dataset.

    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->select('a', $from_html); #get all links
        
    my  $last_link = $parser->last;
    
    # equivalent to ...
    my  $last_link = $parser->data->[(@{$parser->data}-1)];

select_first

The select_first method is a convenience feature combining the select() and first() methods to return the first element from the extracted data.

    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->select_first('a'); #get link text
        $parser->select_first('a', 'href'); #get link URL

select_last

The select_last method is a convenience feature combining the select() and last() methods to return the last element from the extracted data.

    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->select_last('a'); #get link text
        $parser->select_last('a', 'href'); #get link URL

each

The each method is used loop through the extracted dataset. The each method takes one argument, a code reference, and is passed the each extracted item.

    my  $parser = Scrappy::Scraper::Parser->new;
        $parser->select('a', $from_html); #get all links
        
        $parser->each(sub{
            print shift->{href} . "\n"
        });

has_html

The has_html method return a boolean which determine whether HTML content has been set.

    my  $parser = Scrappy::Scraper::Parser->new;
        print 'oh no' unless $parser->has_html;

AUTHOR

Al Newkirk <[email protected]>

COPYRIGHT AND LICENSE

This software is copyright (c) 2010 by awncorp.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.