HTML::Scrubber(3pm)					User Contributed Perl Documentation				       HTML::Scrubber(3pm)

NAME

       HTML::Scrubber - Perl extension for scrubbing/sanitizing html

VERSION

       version 0.09

SYNOPSIS

	   use HTML::Scrubber;

	   my $scrubber = HTML::Scrubber->new( allow => [ qw[ p b i u hr br ] ] );
	   print $scrubber->scrub('<p><b>bold</b> <em>missing</em></p>');
	   # output is: <p><b>bold</b> </p>

	   # more complex input
	   my $html = q[
	   <style type="text/css"> BAD { background: #666; color: #666;} </style>
	   <script language="javascript"> alert("Hello, I am EVIL!");	 </script>
	   <HR>
	       a   => <a href=1>link </a>
	       br  => <br>
	       b   => <B> bold </B>
	       u   => <U> UNDERLINE </U>
	   ];

	   print $scrubber->scrub($html);

	   $scrubber->deny( qw[ p b i u hr br ] );

	   print $scrubber->scrub($html);

DESCRIPTION

       If you wanna "scrub" or "sanitize" html input in a reliable and flexible fashion, then this module is for you.

       I wasn't satisfied with HTML::Sanitizer because it is based on HTML::TreeBuilder, so I thought I'd write something similar that works
       directly with HTML::Parser.

METHODS

       First a note on documentation: just study the EXAMPLE below.  It's all the documentation you could need

       Also, be sure to read all the comments as well as How does it work?.

       If you're new to perl, good luck to you.

   comment
	   warn "comments are  ", $p->comment ? 'allowed' : 'not allowed';
	   $p->comment(0);  # off by default

   process
	   warn "process instructions are  ", $p->process ? 'allowed' : 'not allowed';
	   $p->process(0);  # off by default

   script
	   warn "script tags (and everything in between) are supressed"
	       if $p->script;	   # off by default
	   $p->script( 0 || 1 );

       ** Please note that this is implemented using HTML::Parser's ignore_elements function, so if "script" is set to true, all script tags
       encountered will be validated like all other tags.

   style
	   warn "style tags (and everything in between) are supressed"
	       if $p->style;	   # off by default
	   $p->style( 0 || 1 );

       ** Please note that this is implemented using HTML::Parser's ignore_elements function, so if "style" is set to true, all style tags
       encountered will be validated like all other tags.

   allow
	   $p->allow(qw[ t a g s ]);

   deny
	   $p->deny(qw[ t a g s ]);

   rules
	   $p->rules(
	       img => {
		   src => qr{^(?!http://)}i, # only relative image links allowed
		   alt => 1,		     # alt attribute allowed
		   '*' => 0,		     # deny all other attributes
	       },
	       b => 1,
	       ...
	   );

   default
	   print "default is ", $p->default();
	   $p->default(1);	# allow tags by default
	   $p->default(
	       undef,		# don't change
	       {		# default attribute rules
		   '*' => 1,	# allow attributes by default
	       }
	   );

   scrub_file
	   $html = $scrubber->scrub_file('foo.html');	## returns giant string
	   die "Eeek $!" unless defined $html;	## opening foo.html may have failed
	   $scrubber->scrub_file('foo.html', 'new.html') or die "Eeek $!";
	   $scrubber->scrub_file('foo.html', *STDOUT)
	       or die "Eeek $!"
		   if fileno STDOUT;

   scrub
	   print $scrubber->scrub($html);  ## returns giant string
	   $scrubber->scrub($html, 'new.html') or die "Eeek $!";
	   $scrubber->scrub($html', *STDOUT)
	       or die "Eeek $!"
		   if fileno STDOUT;

       default handler, used by both _scrub and _scrub_fh Moved all the common code (ie all of it) into a single routine for ease of maintenance

       default handler, does the scrubbing if we're scrubbing out to a file.  Now calls _scrub_str and pushes that out to a file.

       default handler, does the scrubbing if we're returning a giant string.  Now calls _scrub_str and appends that to the output string.

How does it work?
       When a tag is encountered, HTML::Scrubber allows/denies the tag using the explicit rule if one exists.

       If no explicit rule exists, Scrubber applies the default rule.

       If an explicit rule exists, but it's a simple rule(1), the default attribute rule is applied.

   EXAMPLE
	   #!/usr/bin/perl -w
	   use HTML::Scrubber;
	   use strict;

	   my @allow = qw[ br hr b a ];

	   my @rules = (
	       script => 0,
	       img => {
		   src => qr{^(?!http://)}i, # only relative image links allowed
		   alt => 1,		     # alt attribute allowed
		   '*' => 0,		     # deny all other attributes
	       },
	   );

	   my @default = (
	       0   =>	 # default rule, deny all tags
	       {
		   '*'		 => 1, # default rule, allow all attributes
		   'href'	 => qr{^(?!(?:java)?script)}i,
		   'src'	 => qr{^(?!(?:java)?script)}i,
	   #   If your perl doesn't have qr
	   #   just use a string with length greater than 1
		   'cite'	 => '(?i-xsm:^(?!(?:java)?script))',
		   'language'	 => 0,
		   'name'	 => 1, # could be sneaky, but hey ;)
		   'onblur'	 => 0,
		   'onchange'	 => 0,
		   'onclick'	 => 0,
		   'ondblclick'  => 0,
		   'onerror'	 => 0,
		   'onfocus'	 => 0,
		   'onkeydown'	 => 0,
		   'onkeypress'  => 0,
		   'onkeyup'	 => 0,
		   'onload'	 => 0,
		   'onmousedown' => 0,
		   'onmousemove' => 0,
		   'onmouseout'  => 0,
		   'onmouseover' => 0,
		   'onmouseup'	 => 0,
		   'onreset'	 => 0,
		   'onselect'	 => 0,
		   'onsubmit'	 => 0,
		   'onunload'	 => 0,
		   'src'	 => 0,
		   'type'	 => 0,
	       }
	   );

	   my $scrubber = HTML::Scrubber->new();
	   $scrubber->allow( @allow );
	   $scrubber->rules( @rules ); # key/value pairs
	   $scrubber->default( @default );
	   $scrubber->comment(1); # 1 allow, 0 deny

	   ## preferred way to create the same object
	   $scrubber = HTML::Scrubber->new(
	       allow   => @allow,
	       rules   => @rules,
	       default => @default,
	       comment => 1,
	       process => 0,
	   );

	   require Data::Dumper,die Data::Dumper::Dumper($scrubber) if @ARGV;

	   my $it = q[
	       <?php   echo(" EVIL EVIL EVIL "); ?>    <!-- asdf -->
	       <hr>
	       <I FAKE="attribute" > IN ITALICS WITH FAKE="attribute" </I><br>
	       <B> IN BOLD </B><br>
	       <A NAME="evil">
		   <A HREF="javascript:alert('die die die');">HREF=JAVA &lt;!&gt;</A>
		   <br>
		   <A HREF="image/bigone.jpg" ONMOUSEOVER="alert('die die die');">
		       <IMG SRC="image/smallone.jpg" ALT="ONMOUSEOVER JAVASCRIPT">
		   </A>
	       </A> <br>
	   ];

	   print "#original text",$/, $it, $/;
	   print
	       "#scrubbed text (default ",
	       $scrubber->default(), # no arguments returns the current value
	       " comment ",
	       $scrubber->comment(),
	       " process ",
	       $scrubber->process(),
	       " )",
	       $/,
	       $scrubber->scrub($it),
	       $/;

	   $scrubber->default(1); # allow all tags by default
	   $scrubber->comment(0); # deny comments

	   print
	       "#scrubbed text (default ",
	       $scrubber->default(),
	       " comment ",
	       $scrubber->comment(),
	       " process ",
	       $scrubber->process(),
	       " )",
	       $/,
	       $scrubber->scrub($it),
	       $/;

	   $scrubber->process(1);	 # allow process instructions (dangerous)
	   $default[0] = 1;		 # allow all tags by default
	   $default[1]->{'*'} = 0;	 # deny all attributes by default
	   $scrubber->default(@default); # set the default again

	   print
	       "#scrubbed text (default ",
	       $scrubber->default(),
	       " comment ",
	       $scrubber->comment(),
	       " process ",
	       $scrubber->process(),
	       " )",
	       $/,
	       $scrubber->scrub($it),
	       $/;

   FUN
       If you have Test::Inline (and you've installed HTML::Scrubber), try

	   pod2test Scrubber.pm >scrubber.t
	   perl scrubber.t

SEE ALSO

       HTML::Parser, Test::Inline, HTML::Sanitizer.

INSTALLATION

       See perlmodinstall for information and options on installing Perl modules.

BUGS AND LIMITATIONS

       No bugs have been reported.

       Please report any bugs or feature requests through the web interface at <http://rt.cpan.org/Public/Dist/Display.html?Name=HTML-Scrubber>.

AVAILABILITY

       The project homepage is <http://search.cpan.org/dist/HTML-Scrubber>.

       The latest version of this module is available from the Comprehensive Perl Archive Network (CPAN). Visit <http://www.perl.com/CPAN/> to
       find a CPAN site near you, or see <http://search.cpan.org/dist/HTML-Scrubber/>.

       The development version lives at <http://github.com/nigelm/html-scrubber> and may be cloned from
       <git://github.com/nigelm/html-scrubber.git>.  Instead of sending patches, please fork this project using the standard git and github
       infrastructure.

AUTHORS

       o   Nigel Metheringham <nigelm@cpan.org>

       o   D. H. <podmaster@cpan.org>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2011 by Nigel Metheringham, 2003-2004 D. H..

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

perl v5.10.1							    2011-04-01						       HTML::Scrubber(3pm)