XHTML::Util - (alpha software) powerful utilities for common but difficult to nail HTML munging.
0.99_08
use strict; use warnings; use XHTML::Util; my $xu = XHTML::Util ->new(\"This is naked\n\ntext for making into paragraphs."); print $xu->enpara, $/; # <p>This is naked</p> # # <p>text for making into paragraphs.</p> $xu = XHTML::Util ->new(\"<blockquote>Quotes should probably have paras.</blockquote>"); print $xu->enpara("blockquote"); # <blockquote> # <p>Quotes should probably have paras.</p> # </blockquote> $xu = XHTML::Util ->new(\'<i><a href="#"><b>Something</b></a>.</i>'); print $xu->strip_tags('a'); # <i><b>Something</b>.</i>
You can use CSS expressions to most of the methods. E.g., to only enpara the contents of div tags with a class of "enpara" -- <div class="enpara"/> -- you could do this-
<div class="enpara"/>
print $xu->enpara("div.enpara");
To do the contents of all blockquotes and divs-
print $xu->enpara("div, blockquote");
Alterations to the XHTML in the object are persistent.
my $xu = XHTML::Util ->new(\'<script>alert("OH HAI")</script>'); $xu->strip_tags('script');
Will remove the script tags—not the script content though—so the next time you call anything that returns the stringified object the changes will remain–
print $xu->as_string, $/; # alert("OH HAI")
Well... really you'll get <![CDATA[alert("OH HAI")]]>.
<![CDATA[alert("OH HAI")]]>
Creates a new XHTML::Util object.
XHTML::Util
Why you might need this-
my $post_title = "I <3 <a href="http://icanhascheezburger.com/">kittehs</a>"; my $blog_link = some_link_maker($post_title); print $blog_link; <a href="/oh-noes">I <3 <a href="http://icanhascheezburger.com/">kittehs</a></a>
That isn't legal so there's no definition for what browsers should do with it. Some sort of tolerate it, some don't. It's never going to be a good user experience.
What you can do is something like this–
my $post_title = "I <3 <a href="http://icanhascheezburger.com/">kittehs</a>"; my $safe_title = $xu->strip_tags($post_title, ["a"]); # Menu link should only go to the single post page. my $menu_view_title = some_link_maker($safe_title); # No need to link back to the page you're viewing already. my $single_view_title = $post_title;
Takes a CSS selector string. Completely removes the matched nodes, including their content. This differs from "strip_tags" which retains the child nodes intact and only removes the tags proper.
# Remove <center/> tags and external images. my $cleaned = $xu->remove("center, img[src^='http']");
Walks the given nodes and executes the given callback. Can be called with a selector or without. If called with a selector, the callback sub receives the selected nodes as its arguments.
$xu->traverse("div.fancy", sub { my $div_node = shift });
Without a selector it receives the document root.
$xu->traverse(sub { my $root = shift });
[Not implemented.] Translates one tag to another.
[Not implemented.] Removes styles from matched nodes. To remove all style from a fragment-
$xu->remove_style("*");
(Should also remove style sheets, yes?)
[Not implemented.] Moves all linked stylesheet information into inline style attributes. This is useful, for example, when distributing a document fragment like an RSS/Atom feed and having it match its online appearance.
[Not implemented.] Upgrades old or broken HTML to valid XHTML.
[Partially implemented.] Attempts to make many known problems go away. E.g., entity escaping, missing alt attributes of images, etc.
Validates a given document or fragment (which is actually contained in a full document) against a DTD provided by name or, if none is provided, it will validate against xhtml1-transitional. Uses XML::LibXML's validate under the covers.
A non-fatal version of "validate". Returns true on success, false on failure.
To add paragraph markup to naked text. There are many, many implementations of this basic idea out there as well as many like Markdown which do much more. While some are decent, none is really meant to sling arbitrary HTML and get DWIM behavior from places where it's left out; every implementation I've seen either has rigid syntax or has beaucoup failure prone edge cases. Consider these-
Is this a paragraph or two? <p>I can do HTML when I'm paying attention.</p> <p style="color:#a00">Or I need to for some reason.</p> Oh, I stopped paying attention... What happens here? Or <i>here</i>? I'd like to see this in a paragraph so it's legal markup. <pre> now this should not be touched! </pre>I meant to do that.
With XHTML::Util->enpara you will get-
XHTML::Util->enpara
<p>Is this a paragraph<br/> or two?</p> <p>I can do HTML when I'm paying attention.</p> <p style="color:#a00">Or I need to for some reason.</p> <p>Oh, I stopped paying attention... What happens here? Or <i>here</i>?</p> <p>I'd like to see this in a paragraph so it's legal markup.</p> <pre> now this should not be touched! </pre> <p>I meant to do that.</p>
The XML::LibXML parser object used to parse (X)HTML.
The XML::LibXML::Document object created from input.
The documentElement of the XML::LibXML::Document object.
The textContent of the root node.
textContent
The head element.
The body element.
Note there is always an implicit head and body even with fragments because libxml creates them, well, we ask it to do so.
Returns the original (intent-wise) fragment or the elements within the body if starting with a full document.
Stringified version of object. If the object was created from an HTML fragment, a fragment will be returned.
Yep. 1-5 with higher giving more info to STDERR.
Returns true if the originally parsed item was a full HTML document.
Returns true if the originally parsed item was a fragment.
Takes another XHTML::Util object or the valid argument to create one. Attempts to determine if the resulting object is the same as the calling object. E.g.,
print $xu->same_same(\"<p>OH HAI</p>") ? "Yepper!\n" : "Noes...\n";
Returns a list of all known HTML tags. Please ignore method. I'm not sure it's a good idea, well named, or will remain.
This wraps "selector_to_xpath" in selector_to_xpath HTML::Selector::Xpath. Not really meant to be used but exposed in case you want it.
print $xu->selector_to_xpath("form[name='register'] input[type='password']"); # //form[@name='register']//input[@type='password']
I think the default doc should be \"". There is no reason to jump through that hoop if wanting to build up something from scratch.
Finish spec and tests. Get it running solid enough to remove alpha label. Generalize the argument handling. Provide optional setting or methods for returning nodes instead of serialized content. Improve document/head related handling/options.
I can see this being easier to use functionally. I haven't decided on the argspec or method-->sub approach for that yet. I think it's a good idea.
All input should be UTF-8 or at least safe to run decode_utf8 on. Regular Latin character sets, I suspect, will be fine but extended sets will probably give garbage or unpredictable results; guessing.
This will wreck XML and probably XHTML with a custom DTD too. It uses HTML::Tagset's conception of what valid tags are. This is not optimal but it is easier than DTD handling. It might improve to more automatic detection in the future.
I have used many of these methods and snippets in many projects and I'm tired of recycling them. Some are extremely useful and, at least in the case of "enpara", better than any other implementation I've been able to find in any language.
That said, a lot of the code herein is not well tested or at least not well tested in this incarnation. Bug reports and good feedback are adored.
XML::LibXML, HTML::Tagset, HTML::Entities, HTML::Selector::XPath, HTML::TokeParser::Simple, CSS::Tiny.
CSS W3Schools, http://www.w3schools.com/Css/default.asp, Learning CSS at W3C, http://www.w3.org/Style/CSS/learning.
git://github.com/pangyre/p5-xhtml-util
Ashley Pond V, ashley at cpan.org.
Copyright (©) 2006-2009.
This program is free software; you can redistribute it or modify it or both under the same terms as Perl itself.
Because this software is licensed free of charge, there is no warranty for the software, to the extent permitted by applicable law. Except when otherwise stated in writing the copyright holders or other parties provide the software "as is" without warranty of any kind, either expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. The entire risk as to the quality and performance of the software is with you. Should the software prove defective, you assume the cost of all necessary servicing, repair, or correction.
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To install XHTML::Util, copy and paste the appropriate command in to your terminal.
cpanm
cpanm XHTML::Util
CPAN shell
perl -MCPAN -e shell install XHTML::Util
For more information on module installation, please visit the detailed CPAN module installation guide.