Migration to OAI Metadata Harvesting Protocol Version 1.1

The XML Schema specification reached W3C recommendation status on May 2, 2001. This has repercussions for the OAI, because version 1.0 of the Metadata Harvesting Protocol built upon the October 2000 XML Schema specification. Therefore, a version 1.1 of the Metadata Harvesting Protocol has been created, that builds upon the May 2001 XML Schema specification.

This document summarizes the changes that OAI data providers will need to implement in order to validate with XML Schema 2001 and OAI Protocol 1.1. This document will also help service providers obtain an understanding of the changes being made.

OAI protocol-replies

First, we list the changes to be made in the XML instance documents sent in response to OAI Protocol requests.

For replies to each verb, the following changes must be made (substituting the actual verb for "<verb>" in the following):

-1.0: xsi:schemaLocation="http://www.openarchives.org/OAI/1.0/OAI_<verb>
1.1: xsi:schemaLocation="http://www.openarchives.org/OAI/1.1/OAI_<verb>

For replies to the Identify request, one additional change is necessary:

-1.0: <protocolVersion>1.0</protocolVersion>
1.1: <protocolVersion>1.1</protocolVersion>

Other schema used by OAI data providers

Next, we list the changes that need to be made to .xsd files involved in OAI communications, e.g. .xsd files defining protocol replies, metadata schema, etc. Each .xsd must be changed as follows:

-1.0: <schema xmlns="http://www.w3.org/2000/10/XMLSchema" ...
1.1:<schema xmlns="http://www.w3.org/2001/XMLSchema" ...

Data providers who currently have their own .xsd files will need to change them. The files that need changing include .xsd schemas defining the following metadata formats: marc21, olac, arXivOld, arXiv, opcit-dc, and perseus.

The OAI provides updated .xsd files in the protocol version 1.1 document: OAI_GetRecord.xsd, OAI_Identify.xsd, OAI_ListMetadataFormats.xsd, OAI_ListSets.xsd, OAI_ListRecords.xsd, OAI_ListIdentifiers.xsd, dc.xsd, eprints.xsd, oai-identifier.xsd, oai_marc.xsd, and rfc1807.xsd.

Metadata and description schema defined by the OAI

Appendix 1 and 2 of version 1.0 of the Metadata Harvesting Protocol list .xsd files that comply to the October 2000 XML Schema specification: dc.xsd, rfc1807.xsd, oai_marc.xsd, oai-identifiers.xsd, and eprints.xsd). The corresponding .xsd files are available at http://www.openarchives.org/OAI/.

In version 1.1 of the Metadata Harvesting Protocol the updated .xsd files will be stored at http://www.openarchives.org/OAI/1.1/.

As a consequence of this directory change, instance documents that use elements defined in these revised schema will have to be modified as follows ("<foo>" stands for dc, rfc1807, oai_marc, oai-identifiers, eprints):

-1.0: xsi:schemaLocation="... http://www.openarchives.org/OAI/<foo>.xsd">
1.1: xsi:schemaLocation="... http://www.openarchives.org/OAI/1.1/<foo>.xsd"


Here are some OAI examples that have been modified to conform to the XML Schema of May 2, 2001. The new bits are colored in red.

An XML instance document responding to the GetRecord request:

<dc xmlns="http://purl.org/dc/elements/1.1/"

A schema (.xsd document) for some community-defined metadata format:

<schema xmlns="http://www.w3.org/2001/XMLSchema"


July 1st 2001