1. 1 herbert van de sompel CS 502 Computing Methods for Digital Libraries Cornell University – Computer Science Herbert Van de Sompel herbertv@cs.cornell.edu Lab : Reference Linking Access to PC orpcuser orpcpw

2. 2 herbert van de sompel Assignment 3: validation of OAI protocol requests Identify request BASE-URL?verb=Identify ListMetadataFormats request BASE-URL?verb= ListMetadataFormats ListSets request BASE-URL?verb= ListSets ListIdentifiers request BASE-URL?verb= ListIdentifiers & from=YYYY-MM-DD & until=YYYY-MM-DD GetRecord request BASE-URL?verb= GetRecord & identifier=xxxxxxx & metadataPrefix=xxxxx GetRecord request BASE-URL?verb= ListRecords & from=YYYY-MM-DD & until=YYYY-MM-DD & set=setSpec

3. 3 herbert van de sompel OAMH protocol replies Real OAMH reply (XML document conforming to defined Schema) for legal protocol requests; HTTP Status-Code 400 for illegal protocol requests: Illegal verbs are used in the request; Illegal arguments are used in the request: The argument itself is illegal as such; The argument is illegal in conjunction with a certain verb; Illegal values are used for valid arguments BUT: it seems to be a mess out there!

4. 4 herbert van de sompel Formalize the notion of legal protocol requests It is possible to transform a GET URL with &-delimited name=value pairs into an XML instance document: http://an.oa.org/request?verb=ListRecords&from=12-01- 1999&until=14-01-1999&set=theset&metadataPrefix=oai_dc 12-01-1999 14-01-1999 oai_dc theset

5. 5 herbert van de sompel Formalize the notion of legal protocol requests It is possible to create an XML Schema that defines which XML instance documents correspond with legal protocol requests. (how stringent can the Schema be?) … ….. …

6. 6 herbert van de sompel Formalize the notion of legal protocol requests Using: such XML instance documents the XML Schema It is possible to check the validity of the XML instance documents against the XML Schema XML document validates => Legal protocol request XML document does not validate => Illegal protocol request The rest: see Assignment 3

7. 7 herbert van de sompel Exploring reference linking solutions – PubMed LinkOut PubMed & LinkOut http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi Publishers, Aggregators, Libraries provide links in XML documents to PubMed PubMed loads these links into the LinkOut linking database Users can set Linkout preferences using the cubby

8. 8 herbert van de sompel Exploring reference linking solutions – OpCit project OpCit http://arabica.ecs.soton.ac.uk/cgi-bin/access_pdf PDF versions of arXiv preprints are parsed for references (dynamic or static) References are identified; essential information is extracted and put on an actionable URL the URL points at a linking server in the demo this linking server is dedicated to arXiv linking it could point at an OpenURL-compliant service component Two interfaces: Reference link only (SFX off) Extended services (SFX on)

9. 9 herbert van de sompel Exploring reference linking solutions – OpenURL SFX Ghent environment Use Netscape Go Edit => Preferences => Advanced => Proxies Choose “manual proxy configuration” sfxserv.rug.ac.be 33334 http://sfxserv.rug.ac.be/execl_eng.cgi name: cs502 pass: lab13 Pick a database – BIOSIS, Inspec, Medline, Current Contents

10. 10 herbert van de sompel Exploring reference linking solutions – PeP Perspectives in Electronic Publishing Use Internet Explorer go http://aims.ecs.soton.ac.uk/Pep.nsf/http://aims.ecs.soton.ac.uk/Pep.nsf/ Click Open Links Session Downloads a linking database to your PC Wherever you travel terms that are in the linking database will become clickable