|
NAMEXML::Validator::Schema - validate XML against a subset of W3C XML SchemaSYNOPSISuse XML::SAX::ParserFactory; use XML::Validator::Schema; # # create a new validator object, using foo.xsd # $validator = XML::Validator::Schema->new(file => 'foo.xsd'); # # create a SAX parser and assign the validator as a Handler # $parser = XML::SAX::ParserFactory->parser(Handler => $validator); # # validate foo.xml against foo.xsd # eval { $parser->parse_uri('foo.xml') }; die "File failed validation: $@" if $@; DESCRIPTIONThis module allows you to validate XML documents against a W3C XML Schema. This module does not implement the full W3C XML Schema recommendation (http://www.w3.org/XML/Schema), but a useful subset. See the SCHEMA SUPPORT section below.IMPORTANT NOTE: To get line and column numbers in the error messages generated by this module you must install XML::Filter::ExceptionLocator and use XML::SAX::ExpatXS as your SAX parser. This module is much more useful if you can tell where your errors are, so using these modules is highly recommeded! INTERFACE
RATIONALEI'm writing a piece of software which uses Xerces/C++ ( http://xml.apache.org/xerces-c/ ) to validate documents against XML Schema schemas. This works very well, but I'd like to release my project to the world. Requiring users to install Xerces is simply too onerous a requirement; few will have it already and the Xerces installation system leaves much to be desired.On CPAN, the only available XML Schema validator is XML::Schema. Unfortunately, this module isn't ready for use as it lacks the ability to actually parse the XML Schema document format! I looked into enhancing XML::Schema but I must admit that I'm not smart enough to understand the code... One day, when XML::Schema is completed I will replace this module with a wrapper around it. This module represents my attempt to support enough XML Schema syntax to be useful without attempting to tackle the full standard. I'm sure this will mean that it can't be used in all situations, but hopefully that won't prevent it from being used at all. SCHEMA SUPPORTSupported ElementsThe following elements are supported by the XML Schema parser. If you don't see an element or an attribute here then you definitely can't use it in a schema document.You can expect that the schema document parser will produce an error if you include elements which are not supported. However, unsupported attributes may be silently ignored. This should not be misconstrued as a feature and will eventually be fixed. All of these elements must be in the http://www.w3.org/2001/XMLSchema namespace, either using a default namespace or a prefix. <schema> Supported attributes: targetNamespace, elementFormDefault, attributeFormDefault Notes: the only supported values for elementFormDefault and attributeFormDefault are "unqualified." As such, targetNamespace is essentially ignored. <element name="foo"> Supported attributes: name, type, minOccurs, maxOccurs, ref <attribute> Supported attributes: name, type, use, ref <sequence> Supported attributes: minOccurs, maxOccurs <choice> Supported attributes: minOccurs, maxOccurs <all> Supported attributes: minOccurs, maxOccurs <complexType> Supported attributes: name <simpleContent> The only supported sub-element is <extension>. <extension> Supported attributes: base Notes: only allowed inside <simpleContent> <simpleType> Supported attributes: name <restriction> Supported attributes: base Notes: only allowed inside <simpleType> <whiteSpace> Supported attributes: value <pattern> Supported attributes: value <enumeration> Supported attributes: value <length> Supported attributes: value <minLength> Supported attributes: value <maxLength> Supported attributes: value <minInclusive> Supported attributes: value <minExclusive> Supported attributes: value <maxInclusive> Supported attributes: value <maxExclusive> Supported attributes: value <totalDigits> Supported attributes: value <fractionDigits> Supported attributes: value <annotation> <documentation> Supported attributes: name <union> Supported attributes: MemberTypes Simple Type SupportSupported built-in types are:string normalizedString token NMTOKEN Notes: the spec says NMTOKEN should only be used for attributes, but this rule is not enforced. boolean decimal Notes: the enumeration facet is not supported on decimal or any types derived from decimal. integer int short byte unsignedInt unsignedShort unsignedByte positiveInteger negativeInteger nonPositiveInteger nonNegativeInteger dateTime Notes: Although dateTime correctly validates the lexical format it does not offer comparison facets (min*, max*, enumeration). double Notes: Although double correctly validates the lexical format it does not offer comparison facets (min*, max*, enumeration). Also, minimum and maximum constraints as described in the spec are not checked. float Notes: The restrictions on double support apply to float as well. duration time date gYearMonth gYear gMonthDay gDay gMonth hexBinary base64Binary anyURI QName NOTATION Miscellaneous DetailsOther known devations from the specification:
CAVEATSHere are a few gotchas that you should know about:
BUGSPlease use "rt.cpan.org" to report bugs in this module:http://rt.cpan.org Please note that I will delete bugs which merely point out the lack of support for a particular feature of XML Schema. Those are feature requests, and believe me, I know we've got a long way to go. SUPPORTThis module is supported on the perl-xml mailing-list. Please join the list if you have questions, suggestions or patches:http://listserv.activestate.com/mailman/listinfo/perl-xml CVSIf you'd like to help develop XML::Validator::Schema you'll want to check out a copy of the CVS tree:http://sourceforge.net/cvs/?group_id=89764 CREDITSThe following people have contributed bug reports, test cases and/or code:Russell B Cecala (aka Plankton) David Wheeler Toby Long-Leather Mathieu h.bridge@fasol.fujitsu.com michael.jacob@schering.de josef@clubphoto.com adamk@ali.as Jean Flouret AUTHORSam Tregar <sam@tregar.com>COPYRIGHT AND LICENSECopyright (C) 2002-2003 Sam TregarThis program is free software; you can redistribute it and/or modify it under the same terms as Perl 5 itself. A NOTE ON DEVELOPMENT METHODOLOGYThis module isn't just an XML Schema validator, it's also a test of the Test Driven Development methodology. I've been writing tests while I develop code for a while now, but TDD goes further by requiring tests to be written before code. One consequence of this is that the module code may seem naive; it really is just enough code to pass the current test suite. If I'm doing it right then there shouldn't be a single line of code that isn't directly related to passing a test. As I add functionality (by way of writing tests) I'll refactor the code a great deal, but I won't add code only to support future development.For more information I recommend "Test Driven Development: By Example" by Kent Beck. SEE ALSOXML::Schemahttp://www.w3.org/XML/Schema http://xml.apache.org/xerces-c/
Visit the GSP FreeBSD Man Page Interface. |