XML::Validate(3pm) User Contributed Perl Documentation XML::Validate(3pm)
NAME
XML::Validate - an XML validator factory
SYNOPSIS
my $validator = new XML::Validate(Type => 'LibXML');
if ($validator->validate($xml)) {
print "Document is valid
";
} else {
print "Document is invalid
";
my $message = $validator->last_error()->{message};
my $line = $validator->last_error()->{line};
my $column = $validator->last_error()->{column};
print "Error: $message at line $line, column $column
";
}
DESCRIPTION
XML::Validate is a generic interface to different XML validation backends. For a list of backend included with this distribution see the
README.
If you want to write your own backends, the easiest way is probably to subclass XML::Validate::Base. Look at the existing backends for
examples.
METHODS
new(Type => $type, Options => \%options)
Returns a new XML::Validate parser object of type $type. For available types see README or use 'BestAvailable' (see "BEST AVAILABLE").
The optional argument Options can be used to supply a set of key-value pairs to the backend parser. See the documentation for
individual backends for details of these options.
validate($xml_string)
Attempts a validating parse of the XML document $xml_string and returns a true value on success, or undef otherwise. If the parse
fails, the error can be inspected using "last_error".
Note that documents which don't specify a DTD or schema will be treated as valid.
For DOM-based parsers, the DOM may be accessed by instantiating the backend module directly and calling the "last_dom" method - consult
the documentation of the specific backend modules. Note that this isn't formally part of the XML::Validate interface as non-DOM-based
validators may added at some point.
last_error()
Returns the error from the last validate call. This is a hash ref with the following fields:
o message
o line
o column
Note that the error gets cleared at the beginning of each "validate" call.
type()
Returns the type of backend being used.
version()
Returns the version of the backend
ERROR REPORTING
When a call to validate fails to parse the document, the error may be retrieved using last_error.
On errors not related to the XML parsing methods will throw exceptions. Wrap calls with eval to catch them.
BEST AVAILABLE
The BestAvailable backend type will check which backends are available and give you the "best" of those. For the default order of
preference see the README with this distribution, but this can be changed with the option PrioritisedList.
If Xerces and LibXML are available the following code will give you a LibXML backend:
my $validator = new XML::Validate(
Type => 'BestAvailable',
Options => { PrioritisedList => [ qw( MSXML LibXML Xerces ) ] },
);
KNOWN ISSUES
There is a bug in versions 1.57 and 1.58 of XML::LibXML that causes an issue related to DTD loading. When a base parameter is used in
conjunction with the load_ext_dtd method the base parameter is ignored and the current directory is used as the base parameter. In other
words, when validating XML with LibXML any base parameter option will be ignored, which may result in unexpected DTD loading errors. This
was reported as bug on November 30th 2005 and the bug report can be viewed here http://rt.cpan.org/Public/Bug/Display.html?id=16213
VERSION
$Revision: 1.25 $ on $Date: 2006/04/19 10:16:19 $ by $Author: mattheww $
AUTHOR
Nathan Carr, Colin Robertson
<cpan _at_ bbc _dot_ co _dot_ uk>
COPYRIGHT
(c) BBC 2005. This program is free software; you can redistribute it and/or modify it under the GNU GPL. See the file COPYING in this
distribution, or http://www.gnu.org/licenses/gpl.txt
perl v5.10.1 2006-04-19 XML::Validate(3pm)