Toby Inkster

NAME

HTML::HTML5::DOM - implementation of the HTML5 DOM on top of XML::LibXML

SYNOPSIS

 use HTML::HTML5::DOM;
 
 # Here $doc is an XML::LibXML::Document...
 my $doc = HTML::HTML5::Parser->load_html(location => 'my.html');
 
 # This upgrades it to an HTML::HTML5::DOM::HTMLDocument...
 XML::LibXML::Augment->rebless($doc);
 
 # What's the page title?
 warn $doc->getElementsByTagName('title')->get_index(1)->text;
 
 # Let's submit the first form on the page...
 my $forms = $doc->getElementsByTagName('form');
 $forms->get_index(1)->submit;

DESCRIPTION

HTML::HTML5::DOM is a layer on top of XML::LibXML which provides a number of additional classes and methods for elements. Because it wraps almost every XML::LibXML method, it is not as fast as using XML::LibXML directly (which is an XS module), but it is more convenient.

DOM Support

HTML::HTML5::DOM implements those parts of the HTML5 DOM which are convenient to do so, and also supports a lot of the pre-HTML5 DOM which was obsoleted by the HTML5 spec. Additionally a number of DOM extensions (methods prefixed with p5_) are provided.

DOM events and event handlers (e.g. onclick) are not supported, and are unlikely to be supported in the foreseeable future.

The CSS bits of DOM are not supported, but may be in the future.

Perl specifics

DOM attributes are typically implemented as get/set/clear methods. For example:

  warn $my_div->id;      # get
  $my_div->id($new_id);  # set
  $my_div->id(undef);    # clear

Methods which return a list usually return a normal Perl list when called in list context, and an XML::LibXML::NodeList (or a subclass of that) when called in list context.

Methods that return a URI generally return one blessed into the URI class.

Methods that return a datetime, generally return one blessed into the DateTime class.

Methods that result in hypertext navigation (e.g. clicking a link or submitting a form) generally return an HTTP::Request object (which you can pass to an LWP::UserAgent or WWW::Mechanize instance).

The standard Perl isa method is overridden to support two additional calling styles:

  $elem->isa( 'h1' );                 # element tag name
  $elem->isa( -HTMLHeadingElement );  # DOM interface name

HTML::HTML5::DOM class methods

While most of the interesting stuff is in HTML::HTML5::DOM::HTMLElement and other classes like that, the HTML::HTML5::DOM package itself provides a handful of methods of its own.

  • XHTML_NS

    Constant. The XHTML namespace URI as a string.

  • getDOMImplementation

    Gets a singleton object blessed into the HTML::HTML5::DOM class.

  • hasFeature

    Given a feature and version, returns true if the feature is supported.

      my $impl = HTML::HTML5::DOM->getDOMImplementation;
      if ($impl->hasFeature('Core', '2.0')) {
        # ... do stuff
      }
  • getFeature

    Given a feature and version, returns an HTML::HTML5::DOMutil::Feature object.

  • registerFeature

    Experimental method to extend HTML::HTML5::DOM.

      my $monkey = HTML::HTML5::DOMutil::Feature->new(Monkey => '1.0');
      $monkey->add_sub(
        HTMLElement => 'talk',
        sub { print "screech!\n" },
      );
      $impl->registerFeature($monkey);
      
      $element->talk if $impl->hasFeature(Monkey => '1.0');
  • parse

    Given a file handle, file name or URL (as a string or URI object), parses the file, returning an HTML::HTML5::DOM::HTMLDocument object.

    This function uses HTML::HTML5::Parser but you can alternatively use XML::LibXML's XML parser:

     my $dom = HTML::HTML5::DOM->parse($fh, using => 'libxml');
  • parseString

    As per parse, but parses a string.

  • createDocument

    Returns an HTML::HTML5::DOM::HTMLDocument representing a blank page.

  • createDocumentType

    Given a qualified name, public identifier (which might be undef) and system identifier (also perhaps undef), returns a doctype tag.

    This is currently returned as a string, but in an ideal world would be an XML::LibXML::Dtd object.

BUGS

http://rt.cpan.org/Dist/Display.html?Queue=HTML-HTML5-DOM.

SEE ALSO

HTML::HTML5::DOM::ReleaseNotes.

General DOM information

HTML5 DOM Specifications: http://www.w3.org/TR/domcore/, http://www.w3.org/TR/html5/index.html#interfaces.

Pre-HTML5 DOM Specifications: http://www.w3.org/TR/2000/REC-DOM-Level-2-Core-20001113/core.html http://www.w3.org/TR/DOM-Level-2-HTML/html.html.

Other packages in this distribution

Packages external to this distribution

"Friends": XML::LibXML, XML::LibXML::Augment, HTML::HTML5::Parser, HTML::HTML5::Writer, HTML::HTML5::ToText, HTML::HTML5::Builder.

"Rivals": HTML::DOM, HTML::Tree.

AUTHOR

Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE

This software is copyright (c) 2012, 2014 by Toby Inkster.

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

DISCLAIMER OF WARRANTIES

THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.