Chris Tijerina
and 2 contributors

NAME

XML::Simple::Sugar - Sugar sprinkled on XML::Simple

VERSION

version v1.1.2

SYNOPSIS

    use Modern::Perl;
    use XML::Simple::Sugar;
    
    my $xs = XML::Simple::Sugar->new;
    
    # Autovivify some XML elements
    my $person = $xs->company->departments->department->person;
    
    # Set some content and attributes
    $person->first_name('John')
           ->last_name('Smith')
           ->email('jsmith@example.com')
           ->salary(60000);
    
    $person->xml_attr( { position => 'Engineer' } );
    
    say $xs->xml_write; 
    
    # <?xml version="1.0"?>
    # <company>
    #   <departments>
    #     <department>
    #       <person position="Engineer">
    #         <email>jsmith@example.com</email>
    #         <first_name>John</first_name>
    #         <last_name>Smith</last_name>
    #         <salary>60000</salary>
    #       </person>
    #     </department>
    #   </departments>
    # </company>

DESCRIPTION

This module is a wrapper around XML::Simple to provide AUTOLOADed accessors to XML nodes in a given XML document. All nodes of the XML document are XML::Simple::Sugar objects having the following attributes and methods.

ATTRIBUTES

xml (XML Str)

This readonly attribute is for use during instantiation (XML::Simple::Sugar->new({ xml => $xml_string })). See also "xml_read".

xml_autovivify (Bool DEFAULT true)

This attribute determines on a per element basis whether new attributes or elements may be introduced. Child elements inherit this setting from their parent. Setting autovivify to false is useful when working with templates with a strict predefined XML structure. This attribute is true by default.

    my $xs = XML::Simple::Sugar->new(
      {
        xml => qq(
            <strict_document>
              <foo>bar</foo>
            </strict_document>
        ),
        xml_autovivify => 0,
      }
    );

    $xs->strict_document->foo('baz'); # Changes bar to baz.  Ok!
    $xs->strict_document->biz('a new element'); # Error!  Biz doesn't exist!

xml_data (XML::Simple compliant Perl representation of an XML document)

This is the Perl representation of the XML. This is ugly to work with directly (hence this module), but in lieu of methods yet unwritten there may be a use case for having direct access to this structure.

xml_index

The index number of an element in a collection

xml_node

The name of the current node

xml_parent

The parent XML::Simple::Sugar object to the current element

xml_xs

This is underlying XML::Simple object. If you need to adjust the XML declaration, you can do that by passing an an XML::Simple object with your preferred options to the new constructor. Be wary of setting other XML::Simple options as this module will happily overwrite anything that conflicts with its assumptions.

xml_root

Returns the root element XML::Simple::Sugar object

METHODS

xml_read (XML Str)

Parses an XML string and sets the data attribute

xml_write

Writes out an XML string

xml_content (Str)

Gets or sets the content of the element

    $xs->person->first_name->xml_content('Bob');

    # Which can be implicitly written
    $xs->person->first_name('Bob');

    # Or using [ index, content, attributes ] notation
    $xs->person->first_name([ 0, 'Bob', undef ]);

    say $xs->person->first_name->xml_content;
    # Bob

xml_attr (HashRef)

Gets or sets the attributes of the element.

    $xs->person->xml_attr( { position => 'Accountant' } );

    # Which can be implicitly written as...
    $xs->person( { position => 'Accountant' } );

    # Or using [ index, content, attributes ] notation
    $xs->person([ 0, undef, { position => 'Accountant' } ]);

    my $attributes = $xs->person->xml_attr;
    say $attributes->{'position'};
    # Accountant

xml_rmattr (Str)

This method removes the passed scalar argument from the element's list of attributes.

xml_nest (XML::Simple::Sugar)

Merges another XML::Simple::Sugar object as a child of the current node.

    my $first_name = XML::Simple::Sugar->new({ xml => '<first_name>Bob</first_name>' });
    $xs->person->xml_nest( $first_name );

    # Or using [ index, content, attributes ] notation
    $xs->person( [ 0, $first_name, undef ] );

Collections

When working with a collection of same-named elements, you can access a specific element by index by passing the collection's name an ArrayRef with the index number. For example:

    my $person2 = $xs->people->person([1]); # Returns the second person element (index 1)

You can also work with the entire collection of individual elements by passing an ArrayRef with the string 'all'.

    my @people = $xs->people->person(['all']); # Returns an array of XML::Simple::Sugar objects

Using [ index, content, attributes ] Notation

When authoring even simple XML documents, using [ index, content, attributes ] notation allows you to implicitly invoke "xml_content", "xml_attr", and "xml_nest" methods on nodes deep within a collection. For example:

    # Sets the position attribute of the second person
    $xs->people->person([ 1, undef, { position => 'Engineer' } ]);

    # Sets the third person's second favorite color to orange
    # with a neon attribute
    $xs->people->person([ 2 ])->favorite_colors->color([ 1, 'orange', { neon => 1 } ]);

    # Composing large documents from smaller ones
    my $xs  = XML::Simple::Sugar->new( {
        xml_xs => XML::Simple->new( XMLDecl => '<!DOCTYPE html>' )
    } );
    my $xs2 = XML::Simple::Sugar->new;

    $xs2->table->tr->th([ 0, 'First Name', { style => 'text-align:left' } ]);
    $xs2->table->tr->th([ 1, 'Last Name' ]);

    $xs->html->body->div([0])->h1('Page Title');
    $xs->html->body->div([ 1, $xs2 ]);

    say $xs->xml_write;

    # <!DOCTYPE html>
    # <html>
    #   <body>
    #     <div>
    #       <h1>Page Title</h1>
    #     </div>
    #     <div>
    #       <table>
    #         <tr>
    #           <th style="text-align:left">First Name</th>
    #           <th>Last Name</th>
    #         </tr>
    #       </table>
    #     </div>
    #   </body>
    # </html>

PLEASE BE ADVISED

Most of the automagic happens with AUTOLOAD. Accessors/mutators and method names in this package cannot be used as element names in the XML document. XML naming rules prohibit the use of elements starting with the string "xml", so "xml_" is used as a prefix for all accessors/mutators/methods to avoid potential document conflicts.

REPOSITORY

https://github.com/Camspi/XML-Simple-Sugar

MINIMUM PERL VERSION SUPPORTED

Perl 5.18.2 or later is required by this module. Lesser Perl versions struggle with deep recursion. Patches welcome.

VERSIONING

Semantic versioning is adopted by this module. See http://semver.org/.

SEE ALSO

CREDITS

  • Jonathan Cast for excellent critique.

  • Kyle Bolton for peeking over my shoulder and giving me pro tips.

  • eMortgage Logic, LLC., for allowing me to publish this module to CPAN

AUTHOR

Chris Tijerina

COPYRIGHT AND LICENSE

This software is copyright (c) 2014-2017 by eMortgage Logic LLC.

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