Note: this specification has been superceded by the Resource Directory Description Language
This version: January 2, 2001
Latest Version: January 2, 2001
Previous Version: January 1, 2000
Editor: Jonathan Borden
Note: you are looking at the actual XML Namespace Catalog for the "http://www.openhealth.org/XMLCatalog/" namespace.
This proposal defines a format for an XML Namespace Catalog. An XML Namespace Catalog serves as a text description of an XML Namespace [1] and includes links to resources associated with the namespace such as schemata, stylesheets and/or other resources associated with the namespace URI. An XML Catalog may also map Formal Public Identifiers into System Identifiers defined as URI references [2]. An XML Namespace Catalog is designed to be suitable for service as the body of a resource returned by deferencing a URI serving as an XML Namespace name.
The XML Namespace Catalog format is an extension of XHTML with a new element named "resource". The resource element serves as an XLink to the referenced resource.
This document defines the syntax and semantics of the XML Namespace Catalog Format, and also serves as an XML Catalog for the namespace http://www.openhealth.org/XMLCatalog/.
The XML Namespace Catalog 1.0 DTD has been produced as an extension of XHTML Basic 1.0 [5].
The resource element is qualified with the namespace URI http://www.openhealth.org/XMLCatalog/
The resource element represents an XLink with two additional attributes public and content-type which provide for optional formal public identifiers and/or content type specifiers.
<!ELEMENT xcat:resource <!ATTLIST xcat:resource %Common.attrib; xmlns:xcat CDATA #FIXED 'http://www.openhealth.org/XMLCatalog/' xlink:type (simple) #FIXED "simple" xlink:role CDATA #IMPLIED xlink:arcrole CDATA #IMPLIED xlink:title CDATA #IMPLIED xlink:href CDATA #REQUIRED public CDATA #IMPLIED -- public identifier content-type CDATA #IMPLIED > |
A URI.
The xlink:arcrole defines the type of the link. [6]
The xlink:arcrole may a schema defining the referenced document, e.g. xhtml, XSD, RDF Schema. In this case such schemata
are named by a URI. The URI should be well known. For example:
XHTML may be referenced by http://www.w3.org/1999/xhtmlXSD may be referenced by http://www.w3.org/2000/10/XMLSchemaRDF Schema may be referenced by http://www.w3.org/2000/01/rdf-schemaA URI.
The xlink:role of the link can be used to distinguish among related
schemata such as for strict, transitional and frameset. The xlink:role of a link should be thought of as the
type of the resource referenced by the link.
A further discussion about the relationships between these attributes and resource types is available in the W3C Note XLink2RDF [6].
Ed. need to further discuss uses of and compare xmlink:arcrole and xlink:role
The xlink:href contains a mandatory URI referencing the target resource
An optional attribute defining the media content type
An optional attribute defining a formal public identifier
The resource element may be placed within the html head or may be placed in the html body. The %Flow.mix entity has been redefined to contain "resource" so it rougly may be placed anywhere a "p" tag may be placed.
This example demonstrates resource within the header:
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xcat="http://www.openhealth.org/XMLCatalog/"> <head> <xcat:resource xlink:type="simple" xlink:arcrole="http://www.w3.org/TR/REC-xml#dt-doctype" xlink:role="http://www.w3.org/TR/xhtml-basic/" xlink:href="http://www.openhealth.org/XMLCatalog/xcat-xhtml.dtd" public="-//XML Catalog//DTD XML Namespace Catalog 1.0//EN" content-type="text/xml-dtd" /> <xcat:resource xlink:type="simple" xlink:title="XHTML1 Strict DTD" xlink:role="http://www.w3.org/tr/xhtml1/DTD/xhtml1-strict.dtd" xlink:arcrole="http://www.w3.org/TR/REC-xml#dt-doctype" xlink:href="xcat-xhtml1-strict.dtd" public="-//XML Catalog//DTD XHTML Strict 1.0//EN" content-type="text/xml-dtd" /> <xcat:resource xlink:type="simple" xlink:title="XHTML1 Transitional DTD" xlink:role="http://www.w3.org/tr/xhtml1/DTD/xhtml1-transitional.dtd" xlink:arcrole="http://www.w3.org/TR/REC-xml#dt-doctype" xlink:href="xcat-xhtml1-transitional.dtd" public="-//XML Catalog//DTD XHTML Transitional 1.0//EN" content-type="text/xml-dtd" /> <xcat:resource xlink:type="simple" xlink:title="XHTML1 Frameset DTD" xlink:role="http://www.w3.org/tr/xhtml1/DTD/xhtml1-frameset.dtd" xlink:arcrole="http://www.w3.org/TR/REC-xml#dt-doctype" xlink:href="xcat-xhtml1-frameset.dtd" public="-//XML Catalog//DTD XHTML Frameset 1.0//EN" content-type="text/xml-dtd" /> <xcat:resource xlink:type="simple" xlink:title="XML Schema" xlink:arcrole="http://www.w3.org/2000/10/XMLSchema" xlink:href="http://www.openhealth.org/XMLCatalog/xcat-xhtml1.xsd" public="-//XML Catalog//XSD XHTML 1.0//EN" content-type="application/xml" /> <xcat:resource xlink:type="simple" xlink:title="OASIS Catalog" xlink:arcrole="http://www.oasis-open.org/html/a401.htm" xlink:href="xcat-xhtml.soc" public="-//XML Catalog//SOC XCAT XHTML 1.0//EN" content-type="application/SGML-Open-Catalog" /> </head> <body>...description goes here ...</body> </html>
In another example resources can be placed within the body, allowing intermingling of text descriptions and resource links.
<html> <head></head> <body> <xcat:resource xlink:type="simple" xlink:title="XML Schema" xlink:arcrole="http://www.w3.org/2000/10/XMLSchema" xlink:href="http://www.openhealth.org/XMLCatalog/xcat-xhtml1.xsd" public="-//XML Catalog//XSD XHTML 1.0//EN" content-type="application/xml" > <p>Here is the description of the XSD Schema being described within a <a class="element" href="#resource">resource</a> tag.</p> </xcat:resource> </body> </html>
Here is the description of the XSD Schema being described within a resource tag.