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Chris Prom Assistant University Archivist University of Illinois at Urbana-Champaign. Do Real Archivists Use OAI? Mid-Atlantic Regional Archives Conference Gettysburg, PA October 31, 2003. http://web.library.uiuc.edu/ahx/workpap/marac03.ppt. Goals. Examine rationale for archivists to use OAI
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Chris Prom Assistant University Archivist University of Illinois at Urbana-Champaign Do Real Archivists Use OAI?Mid-Atlantic Regional Archives ConferenceGettysburg, PAOctober 31, 2003 http://web.library.uiuc.edu/ahx/workpap/marac03.ppt
Goals • Examine rationale for archivists to use OAI • Describe my involvement in the University of Illinois Mellon OAI project • Speculate on OAI’s present and future • Suggest how archivists may wish to get involved with OAI
Should Archivists Use OAI? • OAI use growing, well-supported, (relatively) simple • NSDL base format, NCSTRL project • Allows metasearches across projects and data types (not content specific) • DL projects for archives, manuscripts, photos, artifacts, objects use a variety of metadata standards • Provides wider exposure for collections • University of Michigan OAIster service illustrates both promise and problems
NOT a link to NAACP visual materials finding aid
Found! (. . . 20 mins later) 5,000+ items! (11 online)
UIUC Mellon Project Goals • Test feasibility of harvesting, searching cultural heritage with OAI • Develop data provider tools that produce usable OAI records from disparate sources (MARC, EAD, databases, etc) • Build open-source service provider tools • My role: EAD/OAI • assess structural problems in mapping to OAI • develop an effective crossmapping • allow basic searching in an OAI environment • test effectiveness of the search • provide proof of concept
Our approach • “Dumbing down” metadata has benefits • Examined EAD encoding standards • Generated multiple OAI records for one EAD • top-level record drawn from <eadheader> and <archdesc> • mini records from <dsc>, with relation to top level • Preserve context for “hits” by linking user to finding aid in the search/retrieval mechanism • relations between levels in the finding aid rendered implicitly by our service provider, not within the OAI record
Our Data and Service Providers • OAI Repository (Data Provider) • Snapshot of ~5,500 EAD finding aids mirrored on UIUC server • responds to HTTP get and post with ASP scripts and XSLT stylesheet to provide requested data • Records produced from EAD include XPointer • When EADs are split into their subordinate components, Xpointers identify the individual parts • Service Provider • Server-side scripts use the XPointers in DC identifier tag for rendering and linking • Xpointer used to move user deep in finding aid, preserve context
XPointer • WC3 Recommendation, March 2003: http://www.w3.org/XML/Linking • Can identify XML fragments using a superset of the XPath syntax, e.g. xyz.xml#xpointer(//dsc[1]/c01[2]/c02[3]/c03[10]) • When EADs are split into their subordinate components, Xpointers identify the individual parts • To make it work, both data providers and service providers would need to share a set of assumptions about HOW it should work
<rdf:RDF> <rdf:Description> <dc:identifier> http://…/…/test.xml#xpointer(//dsc[1]/c01[8]/c02[5]/c03[244]) </dc:identifier> <dc:title>Toensing, Richard</dc:title> <dc:type>text</dc:type> <dc:type>archives or manuscripts</dc:type> <dc:type>file</dc:type> <dcterms:isPartOf> <rdf:Description> <dc:identifier> http://…/…/test.xml#xpointer(//dsc[1]/c01[8]/c02[5]) </dc:identifier> <dc:title>Various Composers</dc:title> </rdf:Description> </dcterms:isPartOf> </rdf:Description> </rdf:RDF>
What I learned • Using OAI can exposure your collections to new audiences • Not good enough to harvest from image databases, nor just give just top-level link to FA • But many users confused when stumble on a finding aid; “where’s the beef” • An “archives friendly” service provider would • . . . Serve as basis for cross-repository searches • . . . Reenginner the notion of what is a finding aid by allowing access from the back end • . . . Undo some of the damage inflicted when archival materials are treated as items • . . . need to reconstruct context using local mirrors of the ead document
The Future • OAI Currently better suited to representing digital objects than descriptive data • Service providers currently limited in number, 16 listed on openarchives.org • Will OAI take off? • IMLS Digital Collections and Content Project: (http://imlsdcc.grainger.uiuc.edu/)
Data Provider Options • If you want to provide dynamic (full) OAI metadata • Metadata items in Relational database • Map fields or pages to DC record • Use webscripting language to respond to harvester requests • XML, e.g. Finding aid (as a digital object) • map from <eadheader> and <archdesc> • use encodinganalog recommendations from RLG Best Practices or pass entire EAD file with XSD schema • metadata for digital objects linked from EAD??? • use XSLT and XPointer to provide context and allow service providers to replicate hierarchical structure of EAD. • Depends on SP’s ability to handle xpointer
Data Provider Options, cont. • Static OAI metadata • Suitable for small collections which are not growing • All metadata should be contained in a single xml file on a webserver • Projects which will harvest metadata (e.g. IMLS Digital Collections and Content) may be able to provide assistance in conversion.
Resources • OAI website: • http://www.openarchives.org/ • UIUC Provider Tools • http://uilib-oai.sourceforge.net/ • http://sourceforge.net/projects/uilib-ead/ • Library Hi Tech, Vol 21, No. 2, special issue on OAI • Further implementation guidelines • http://dli.grainger.uiuc.edu/publications/twcole/jcdl-oai/JCDL_2003_OAI_Intro.ppt • This powerpoint: • http://web.library.uiuc.edu/ahx/workpap/marac03.ppt
Chris Prom Assistant University Archivist University of Illinois at Urbana-Champaign Do Real Archivists Use OAI?Mid-Atlantic Regional Archives ConferenceGettysburg, PAOctober 31, 2003 http://web.library.uiuc.edu/ahx/workpap/marac03.ppt