XML & Library Applications

1. XML & Library Applications ELAG 2001 Poul Henrik Jørgensen, phj@dbc.dk Danish Bibliographic Centre, www.dbc.dk

2. Objective • To identify family of relevant XML standards • To describe existing use of XML standards within important Bibliographic IT standards • To identify future development of Bibliographic IT standards based on XML standards • Not an introductory course in the XML standards themselves! Poul Henrik Jørgensen

3. Content • XML Standards Overview • Major benefits of XML • MARC formats and XML • Z39.50 and XML formats • Interlibrary Loan transactions in XML • NISO Circulation Interchange Protocol and XML • ZML: Z39.50 as XML Protocol • RDF: Semantic Web and Metadata Poul Henrik Jørgensen

4. XML Standards Overview • Family of related standards from W3C • XML: Representation of hierarchical data • XML Schema: Specification of XML structure • XHTML: Presentation/display of data • DOM: Internal representation of XML • XSLT/XPath: Transformation of XML • RDF: Relationships between Objects and Classes Poul Henrik Jørgensen

5. Major benefits of XML • Easy to understand by humans – as well as by computers • Supported by all mainstream IT vendors • Handles hierarchical information well • Can be edited by simple tools • Many IT people knows XML Poul Henrik Jørgensen

6. OAI MARC XML Schema • Developed for Open Archives Initiative • Similar to limited ISO 2709 structure • Single Field element type containing single Subfield element type • Field- and Subfield instances identified by attribute values • Suitable for exchange and conversions • http://www.openarchives.org/OAI/oai_marc.xsd Poul Henrik Jørgensen

7. MARC XML Schemas • Developed for VisualCat and ONE-2 project • Similar to LC MARC DTD • Each possible combination of Field and Subfield specified as separate XML Element Types • danMARC2: 164 MARC Fields and 1189 Subfields • Suitable for automatic syntax validation • Schemas for MARC21 (British Library), UNIMARC (Italian SBN) and danMARC2 (DBC) Poul Henrik Jørgensen

8. VisualCat MARC21 Schema Poul Henrik Jørgensen

9. Z39.50 and XML formats • CompSpec option may specify Record Syntax, Schema, and Element Specification: • recordSyntax identifies format, e.g. XML (OID= 1.2.840.10003.5.109.10) • Schema identifies structure e.g. Holdings(OID=1.2.840.10003.13.7.1) • elementSpec identifies subset, e.g. Level B-1: Minimal Bibliographic Level Holdings (ESN=”B1”) Poul Henrik Jørgensen

10. XML Schemas in Z39.50 • Dublin Core XML format • http://www.nlc-bnc.ca/bath/bp-app-d.htm • http://www.openarchives.org/OAI/dc.xsd • ExplainLite XML DTD • http://www.one-2.org/technical/ONE-ICONE-DTD-0001.dtd • Holdings XML Schema • http://www.portia.dk/zholdings/Holdings6a/HoldingsSchema6a_xsd/HoldingsSchema6a.htm • ES Task Package XML format Poul Henrik Jørgensen

11. Dublin Core (Bath Profile) <record-list> <dc-record> <creator>some author</creator> <creator>some author</creator> <title>some title</title> </dc-record> <dc-record> ..... </dc-record> </record-list> Poul Henrik Jørgensen

12. ExplainLite (VisualCat) Poul Henrik Jørgensen

13. Holdings XML (danZIG) <?xml version="1.0" encoding="UTF-8" ?> <!--ZIG XML Holdings B-2/A danZIG example --> <!--Produced by Poul Henrik Jorgensen 2001-05-21 --> <holdingsStructure xmlns:xsi="http://www.w3.org/2000/10/XMLSchema-instance" xsi:noNamespaceSchemaLocation="http://www.portia.dk/zholdings/Holdings6a/HoldingsSchema6a.xsd"> <bibItemInfo-1targetItemId-3="001 field in DanBib" /> <!--holdingsStatement repeated for each location --> <holdingsStatement-4 unionCatShelfMark-9="Local Shelf Mark" holdingsNotes-25="Holdings of serials"> <holdingsSiteLocation-6targetLocationId-26="Identificator in local system" institutionOrSiteId-27="Library Number" networkAddress-33="Z39.50URL" siteNotes-34="Availability" /> <unionCatLendingInfo-19servicePolicy-109="1 eller 2 cf. danZIG note" /> </holdingsStatement-4> </holdingsStructure> Poul Henrik Jørgensen

14. ILL transactions in XML • ICCU/SBN system offers XML Item-Order request messages (APDU) via E-mail • ONE-2 Profile of all ILL messages in XML • http://www.portia.dk/pubs/ill/schema/illv2/illv2.htm • New danZIG Profile using XML for Z39.50/ILL Profile 1 Poul Henrik Jørgensen

15. Circulation Interchange Protocol • NISO Circulation Interchange Protocol • http://www.niso.org/commitat.html • NCIP Data specified by XML DTD/Schema • http://www.portia.dk/pubs/NCIP/NCIP_v0_1a.xsd • Adapted to SOAP/WSDL • http://www.portia.dk/pubs/NCIP/PortTypes.wsdl Poul Henrik Jørgensen

16. ZML Objectives • Initiative by Library of Congress and others • Leverage investments in existing Z39.50 Services and specifications • Simplify Z39.50 implementation • Facilitate interoperability with other relevant standards • Foster migration of Z39.50 functionality to mainstream IT technologies Poul Henrik Jørgensen

17. ZML: Z39.50 over SOAP • Protocol elements encoded as XML Structures • Relevant Z39.50 Services mapped to SOAP Request/Response functions over HTTP • Search/Present and other services simplified • Existing Web-to-Z gateways may be enhanced with SOAP-to-Z gateways • Draft specifications to be presented at ZIG in October 2001 at British Library in York Poul Henrik Jørgensen

18. Semantic Web and RDF • RDF is part of W3C Semantic Web Activity • http://www.w3.org/2001/sw/Activity • Defines relationships and attributes of electronic resources • Can represent any metadata schema, e.g. Dublin Core or IFLA FRBR metadata • RDF is expressed by directed graphs or XML • RDF is used to represent Authority Data and other metadata Poul Henrik Jørgensen

19. FRBR RDF graph (VisualCat) Poul Henrik Jørgensen

20. Summary • XML offers many inherent advantages as data format • XML standards are already implemented in relation to MARC, Z39.50, ILL and NCIP • Next generation of Z39.50 (i.e. ZML) will most likely be based on XML standards • ”Digital Libraries may be the killer application for RDF” Poul Henrik Jørgensen