NAME

XML::Quick - Generate XML from hashes (and other data)

SYNOPSIS

use XML::Quick;

$xml = xml($data);

$xml = xml($data, { ... });

DESCRIPTION

This module generates XML from Perl data (typically a hash). It tries hard to produce something sane no matter what you pass it. It probably fails.

The simplest thing you can do is xml() a basic string. It will be XML-escaped for you:

xml('v&lue');

# produces: v&lue

To create a simple tag, you'll need to pass a hash instead:

xml({
      'tag' => 'value'
    });

# produces: <tag>value</tag>

Of course you can have several tags in the same hash:

xml({
      'tag' => 'value',
      'tag2' => 'value2'
    });

# produces: <tag2>value2</tag2>
#           <tag>value</tag>

Arrays will be turned into multiple tags with the same name:

xml({
      'tag' => [
                 'one',
                 'two',
                 'three'
               ]
    });

# produces: <tag>one</tag>
#           <tag>two</tag>
#           <tag>three</tag>

Use nested hashes to produce nested tags:

xml({
      'tag' => {
                 'subtag' => 'value'
               }
    });

# produces: <tag>
#             <subtag>value</subtag>
#           </tag>

A hash key with a value of undef or an empty hash or array will produce a "bare" tag:

xml({
      'tag' => undef
    });

# produces: <tag/>

Adding attributes to tags is slightly more involved. To add attributes to a tag, include its attributes in a hash stored in the _attrs key of the tag:

   xml({
         'tag' => {
                    '_attrs' => {
                                  'foo' => 'bar'
                                }
                  }
       });

   # produces: <tag foo='bar'/>

Of course, you're probably going to want to include a value or other tags inside this tag. For a value, use the _cdata key:

xml({
      'tag' => {
                 '_attrs' => {
                               'foo' => 'bar'
                             },
                 '_cdata' => 'value'
               }
    });

# produces: <tag foo='bar'>value</tag>

For nested tags, just include them like normal:

xml({
      'tag' => {
                 '_attrs' => {
                               'foo' => 'bar'
                             },
                 'subtag' => 'value'
               }
    });

# produces: <tag foo='bar'>
#             <subtag>subvalue</subtag>
#           </tag>

If you wanted to, you could include both values and nested tags, but you almost certainly shouldn't. See "BUGS AND LIMITATIONS" for more details.

There are also a number of processing options available, which can be specified by passing a hash reference as a second argument to xml():

• root

  Setting this will cause the returned XML to be wrapped in a single toplevel tag.

  xml({ tag => 'value' });
  # produces: <tag>value</tag>
  
  xml({ tag => 'value' }, { root => 'wrap' });
  # produces: <wrap><tag>value</tag></wrap>

• attrs

  Used in conjuction with the root option to add attributes to the root tag.

  xml({ tag => 'value' }, { root => 'wrap', attrs => { style => 'shiny' }});
  # produces: <wrap style='shiny'><tag>value</tag></wrap>

• cdata

  Used in conjunction with the root option to add character data to the root tag.

  xml({ tag => 'value' }, { root => 'wrap', cdata => 'just along for the ride' });
  # produces: <wrap>just along for the ride<tag>value</tag></wrap>

  You probably don't need to use this. If you just want to create a basic tag from nothing do this:

  xml({ tag => 'value' });

  Rather than this:

  xml('', { root => 'tag', cdata => 'value' });

  You almost certainly don't want to add character data to a root tag with nested tags inside. See "BUGS AND LIMITATIONS" for more details.

• escape

  A flag, enabled by default. When enabled, character data values will be escaped with XML entities as appropriate. Disabling this is useful when you want to wrap an XML string with another tag.

  xml("<xml>foo</xml>", { root => 'wrap' })
  # produces: <wrap>&lt;xml&gt;foo&lt;/xml&gt;</wrap>
  
  xml("<xml>foo</xml>", { root => 'wrap', escape => 0 })
  # produces: <wrap><xml>foo</xml></wrap>

DEPENDENCIES

Requires Perl6::Export::Attrs, Scalar::Util

AUTHOR

Robert Norris (Robert.Norris@its.monash.edu.au)

BUGS AND LIMITATIONS

Because Perl hash keys get randomised, there's really no guarantee the generated XML tags will be in the same order as they were when you put them in the hash. This generally won't be a problem as the vast majority of XML-based datatypes don't care about order. I don't recommend you use this module to create XML when order is important (eg XHTML, XSL, etc).

Things are even more hairy when including character data alongside tags via the cdata or _cdata options. The cdata options only really exist to allow attributes and values to be specified for a single tag. The rich support necessary to support multiple character data sections interspersed alongside tags is entirely outside the scope of what the module is designed for.

There are probably bugs. This kind of thing is an inexact science. Feedback welcome.

COPYRIGHT

Copyright (c) 2005 Monash University. All Rights Reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

cpanm XML::Quick

perl -MCPAN -e shell
install XML::Quick