WI#58: standard hierarchy schema

Given the resolution of WI#9 (hierarchical resources), there need
to be standard schemas for certain common hierarchies such as
UFS.

Following is an attempt to define one such a schema.  I think it
would be suitable for use with UFS, most other file systems, and
for many other types of hierarchies.  Such a schema could either
be included as an appendix in XACML 2.0, or could be in a
separate profile.  It is so general, however, that I think
inclusion in an XACML 2.0 appendix might be appropriate.

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema targetNamespace="urn:oasis:names:tc:xacml:2.0:hierarchy-schema" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:hs="urn:oasis:names:tc:xacml:2.0:hierarchy-schema" elementFormDefault="qualified" attributeFormDefault="unqualified">
	<!-- -->
	<xs:element name="Hierarchy" type="hs:HierarchyType"/>
	<xs:complexType name="HierarchyType">
		<xs:sequence>
			<xs:element name="RootName" type="xs:anyURI"/>
            <xs:element ref="hs:Node" maxOccurs="unlimited"/>
        </xs:sequence>
    </xs:complexType>
    <!--  -->
    <xs:element name="Node" type="hs:NodeType"/>
    <xs:complexType name="NodeType">
        <xs:sequence>
            <xs:element name="hs:NodeName" type="xs:string"/>
            <xs:element ref="hs:Node" minOccurs="0" maxOccurs="unlimited"/>
    </xs:complexType>
</xs:schema>

Text:

Where possible, the hierarchy schema defined in
urn:oasis:names:tc:xacml:2.0:hierarchy-schema SHOULD be used for
expressing hierarchical resources in the
urn:oasis:names:tc:xacml:1.0:resource:resource-content Attribute.
For example, this schema allows a web page hierarchy to be
expressed as:

   <hs:Hierarchy>
      <hs:RootName>file://research.sun.com</hs:RootName>
      <hs:Node>
         <hs:NodeName>people</hs:NodeName>
      </hs:Node>
      <hs:Node>
         <hs:NodeName>projects</hs:NodeName>
         <hs:Node>
            <hs:NodeName>GCspy</hs:NodeName>
         </hs:Node>
         <hs:Node>
            <hs:NodeName>Barcelona</hs:NodeName>
         </hs:Node>
      </hs:Node>
      <hs:Node>
         <hs:NodeName>features</hs:NodeName>
         <hs:Node>
            <hs:NodeName>jackpot</hs:NodeName>
            <hs:Node>
               <hs:NodeName>specification</hs:NodeName>
            </hs:Node>
            <hs:Node>
               <hs:NodeName>presentation</hs:NodeName>
            </hs:Node>
         </hs:Node>
         <hs:Node>
            <hs:NodeName>4g_wireless</hs:NodeName>
         </hs:Node>
      </hs:Node>
    </hs:Hierarchy>

Similarly, this schema can be used for for various types of file
system hierarchies.

-- 
Anne H. Anderson             Email: 
Sun Microsystems Laboratories
1 Network Drive,UBUR02-311     Tel: 781/442-0928
Burlington, MA 01803-0902 USA  Fax: 781/442-1692