OAI-PMH
Aus Geoinformation HSR
'Open Archives Initiative Protocol for Metadata Harvesting'
Inhaltsverzeichnis
Description
- Leightweight:
- A low barrier interoperability specification
- RESTful: HTTP based, GET / POST requests, XML responses
- Clear concepts:
- Based around metadata harvesting model (metadata aggregation and syndication)
- Metadata about resources, mandates unqualified Dublin Core as default
- Not a search protocol! That could be for example enhanced or merged versions of OpenSearch/GeoRSS and SRU/SRW besides WFS.
- Extendable: Has extension mechanism for more domain specific metadata models
- Stable: OAI has committed to making subsequent revisions of the protocol backwards compatible.
- Established: Implemented - among others - by Google, CiteSeer and MSN as well as by dozens of open source tools, like OAICat (Java) or mod_oai (C, installed at 500 sites); see more tools in the Weblinks section below.
There are following alternatives (Remarks: all considered either inappropriate or not established or at least 'painfull' compared to OAI-PMH):
- Z39.50 and SRW - the more leightweight and 'modern' successor of Z39.50
- UDDI - the SOAP thing
- WFS - the OGC thing
Architecture
Specifications
- OAI-PMH 2.0 Spec. - Specification for Open Archives Initiative Protocol for Metadata Harvesting 2.0
- OAI-PMH Static Repository 2.0 Spec. - Specification for an OAI Static Repository and an OAI Static Repository Gateway 2.0
For Tools and Demos see Weblinks section below.
Weblinks
- Tutorials and short explanations:
- Concise technical description of the protocol
- OAI for beginners, OAI and OAI-PMH for absolute beginners by Philip Hunter, 2005.
- Papers:
- Haixia Mao (2005), OAI-PMH Based Interoperation For Spatial Metadata. In: ISPRS Workshop on Service and Application of Spatial Data Infrastructure, XXXVI(4/W6), Oct.14-16 2005, Hangzhou, China.
- Use of OAI to disclose metadata as an output from the portal From: Go-Geo! Geo-Data Portal Project
- 'Open Content and Access for Digital Scholarship' by Gerry McKiernan, 2004 (describes use of map resources)
- Software and Tools:
- OAI-PMH Data Provider Components (open source):
- OAI tools list
- Java: OAICat
- PHP: hu-berlin.de, ...
- OAI-PMH Static Repository Gateways (open source):
- srepod - OAI-PMH Static Repository Gateway (C)
- Digital Repository System Software (open source):
- DSpace (Java)
- OAI-PMH Data Provider Components (open source):
- Demos and examples:
- Demo of OAICat - The OAICat Open Source project is a Java Servlet web application providing an OAI-PMH v2.0 repository framework.
- OAIster - Most often mentioned collection of freely available, previously difficult-to-access, academically-oriented digital resources that are easily searchable by anyone.
- PKP Open Archives Harvester - Free metadata indexing system developed by the Public Knowledge Project through its federally funded efforts to expand and improve access to research.
- OJAX Demo - Federated Metasearch Service using Ajax/Lucene