Provided by: libxml-semanticdiff-perl_1.0005-1_all 
NAME
XML::SemanticDiff - Perl extension for comparing XML documents.
VERSION
version 1.0005
SYNOPSIS
use XML::SemanticDiff;
my $diff = XML::SemanticDiff->new();
foreach my $change ($diff->compare($file, $file2)) {
print "$change->{message} in context $change->{context}\n";
}
# or, if you want line numbers:
my $diff = XML::SemanticDiff->new(keeplinenums => 1);
foreach my $change ($diff->compare($file, $file2)) {
print "$change->{message} (between lines $change->{startline} and $change->{endline})\n";
}
DESCRIPTION
XML::SematicDiff provides a way to compare the contents and structure of two XML
documents. By default, it returns a list of hashrefs where each hashref describes a single
difference between the two docs.
VERSION
version 1.0005
METHODS
$obj->new([%options])
Ye olde object constructor.
The new() method recognizes the following options:
• keeplinenums
When this option is enabled XML::SemanticDiff will add the 'startline' and 'endline'
properties (containing the line numbers for the reported element's start tag and end
tag) to each warning. For attribute events these numbers reflect the start and end
tags of the element which contains that attribute.
• keepdata
When this option is enabled XML::SemanticDiff will add the 'old_value' and 'new_value'
properties to each warning. These properties contain, surprisingly, the old and new
values for the element or attribute being reported.
In the case of missing elements or attributes (those in the first document, not in the
second) only the 'old_value' property will be defined. Similarly, in the case of rogue
elements or attributes (those in the second document but not in the first) only the
'new_value' property will be defined.
Note that using this option will greatly increase the amount of memory used by your
application.
• diffhandler
Taking a blessed object as it's sole argument, this option provides a way to hook the
basic semantic diff engine into your own custom handler class.
Please see the section on 'CUSTOM HANDLERS' below.
• ignorexpath
This option takes array of strings as argument. Strings are interpreted as simple
xpath expressions. Nodes matching these expressions are ignored during comparison. All
xpath expressions should be absolute (start with '/').
Current implementation ignores namespaces during comparison.
@results = $differ->compare($xml1, $xml2)
Compares the XMLs $xml1 and $xml2 . $xml1 and $xml2 can be:
• filenames
This will be considered if it is a string that does not contain newlines and exists in
the filesystem.
• the XML text itself.
This will be considered if it's any kind of string.
• the results of read_xml(). (see below)
This will be considered if it's a hash reference.
my $doc = read_xml($xml_location)
This will read the XML, process it for comparison and return it. See compare() for how it
is determined.
CUSTOM HANDLERS
Internally, XML::SemanticDiff uses an event-based model somewhat reminiscent of SAX where
the various 'semantic diff events' are handed off to a separate handler class to cope with
the details. For most general cases where the user only cares about reporting the
differences between two docs, the default handler, XML::SemanticDiff::BasicHandler, will
probably suffice. However, it is often desirable to add side-effects to the diff process
(updating datastores, widget callbacks, etc.) and a custom handler allows you to be
creative with what to do about differences between two XML documents and how those
differences are reported back to the application through the compare() method.
HANDLER METHODS
The following is a list of handler methods that can be used for your custom diff-handler
class.
init($self, $diff_obj)
The "init" method is called immediately before the the two document HASHes are compared.
The blessed XML::SemanticDiff object is passed as the sole argument, so any values that
you wish to pass from your application to your custom handler can safely be added to the
call to XML::SemanticDiff's constructor method.
rogue_element($self, $element_name, $todoc_element_properties)
The "rogue_element" method handles those cases where a given element exists in the to-file
but not in the from-file.
missing_element($self, $element_name, $fromdoc_element_properties)
The "missing_element" method handles those cases where a given element exists in the from-
file but not in the to-file.
element_value($self, $element, $to_element_properties, $fromdoc_element_properties)
The "element_value" method handles those cases where the text data differs between two
elements that have the same name, namespace URI, and are at the same location in the
document tree. Note that all whitespace is normalized and the text from mixed-content
elements (those containing both text and child elements mixed together) is aggregated down
to a single value.
namespace_uri($self, $element, $todoc_element_properties, $fromdoc_element_properties)
The "namespace_uri" method handles case where the XML namespace URI differs between a
given element in the two documents. Note that the namespace URI is checked, not the
element prefixes since <foo:element/> <bar:element/> and <element/> are all considered
equivalent as long as they are bound to the same namespace URI.
rogue_attribute($self, $attr_name, $element, $todoc_element_properties)
The "rogue_attribute" method handles those cases where an attribute exists in a given
element the to-file but not in the from-file.
missing_attribute($self, $attr_name, $element, $todoc_element_properties,
$fromdoc_element_properties)
The "missing_attribute" method handles those cases where an attribute exists in a given
element exists in the from-file but not in the to-file.
attribute_value($self, $attr_name, $element, $todoc_element_properties,
$fromdoc_element_properties)
The "attribute_value" method handles those cases where the value of an attribute varies
between the same element in both documents.
final($self, $diff_obj)
The "final" method is called immediately after the two document HASHes are compared. Like
the "init" handler, it is passed a copy of the XML::SemanticDiff object as it's sole
argument.
Note that if a given method is not implemented in your custom handler class,
XML::SemanticDiff will not complain; but it means that all of those events will be
silently ignored. Consider yourself warned.
AUTHOR
Originally by Kip Hampton, khampton@totalcinema.com .
Further Maintained by Shlomi Fish, <http://www.shlomifish.org/> .
COPYRIGHT
Copyright (c) 2000 Kip Hampton. All rights reserved. This program is free software; you
can redistribute it and/or modify it under the same terms as Perl itself.
Shlomi Fish hereby disclaims any implicit or explicit copyrights on this software.
LICENSE
This program is free software; you can redistribute it and/or modify it under the same
terms as Perl itself.
SEE ALSO
perl(1).
AUTHOR
Shlomi Fish <shlomif@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2001 by Kim Hampton.
This is free software; you can redistribute it and/or modify it under the same terms as
the Perl 5 programming language system itself.
BUGS
Please report any bugs or feature requests on the bugtracker website
http://rt.cpan.org/Public/Dist/Display.html?Name=XML-SemanticDiff or by email to
bug-xml-semanticdiff@rt.cpan.org.
When submitting a bug or request, please include a test-file or a patch to an existing
test-file that illustrates the bug or desired feature.
SUPPORT
Perldoc
You can find documentation for this module with the perldoc command.
perldoc XML::SemanticDiff
Websites
The following websites have more information about this module, and may be of help to you.
As always, in addition to those websites please use your favorite search engine to
discover more resources.
• MetaCPAN
A modern, open-source CPAN search engine, useful to view POD in HTML format.
<http://metacpan.org/release/XML-SemanticDiff>
• Search CPAN
The default CPAN search engine, useful to view POD in HTML format.
<http://search.cpan.org/dist/XML-SemanticDiff>
• RT: CPAN's Bug Tracker
The RT ( Request Tracker ) website is the default bug/issue tracking system for CPAN.
<https://rt.cpan.org/Public/Dist/Display.html?Name=XML-SemanticDiff>
• AnnoCPAN
The AnnoCPAN is a website that allows community annotations of Perl module
documentation.
<http://annocpan.org/dist/XML-SemanticDiff>
• CPAN Ratings
The CPAN Ratings is a website that allows community ratings and reviews of Perl
modules.
<http://cpanratings.perl.org/d/XML-SemanticDiff>
• CPAN Forum
The CPAN Forum is a web forum for discussing Perl modules.
<http://cpanforum.com/dist/XML-SemanticDiff>
• CPANTS
The CPANTS is a website that analyzes the Kwalitee ( code metrics ) of a distribution.
<http://cpants.cpanauthors.org/dist/XML-SemanticDiff>
• CPAN Testers
The CPAN Testers is a network of smokers who run automated tests on uploaded CPAN
distributions.
<http://www.cpantesters.org/distro/X/XML-SemanticDiff>
• CPAN Testers Matrix
The CPAN Testers Matrix is a website that provides a visual overview of the test
results for a distribution on various Perls/platforms.
<http://matrix.cpantesters.org/?dist=XML-SemanticDiff>
• CPAN Testers Dependencies
The CPAN Testers Dependencies is a website that shows a chart of the test results of
all dependencies for a distribution.
<http://deps.cpantesters.org/?module=XML::SemanticDiff>
Bugs / Feature Requests
Please report any bugs or feature requests by email to "bug-xml-semanticdiff at
rt.cpan.org", or through the web interface at
<https://rt.cpan.org/Public/Bug/Report.html?Queue=XML-SemanticDiff>. You will be
automatically notified of any progress on the request by the system.
Source Code
The code is open to the world, and available for you to hack on. Please feel free to
browse it and play with it, or whatever. If you want to contribute patches, please send me
a diff or prod me to pull from your repository :)
<https://github.com/shlomif/perl-XML-SemanticDiff>
git clone https://github.com/shlomif/perl-XML-SemanticDiff.git