Difference between revisions of "Metacat OAI Provider"

Revision as of 13:03, 13 February 2009

UNM is creating an OAI-PMH provider to add on to Metacat.

Requirements

• Our primary goal is to enhance access, not to provide a failover copy. It is ok for Dryad to only store the Dryad-format metadata, and not use the full EML.
• Metacat exposes all metadata through an OAI-PMH provider.
• The provider makes all data available in these formats:
  • Simple DC
  • Dryad application profile (qualified DC with extensions)
  • EML
• Dryad harvests all metadata exposed by Metacat.
  • The record in Dryad must point to the record in Metacat, enabling users to find the actual datasets.
• Metacat harvests metadata from the Dryad OAI-PMH server, and makes it available alongside the native Metacat metadata.
• Not an actual requirement, but keep in mind that we need to eventually download the data files.

Tasks

• Ryan/Mark: schedule a bi-weekly call to touch base on progress.
• Mark: discuss with Matt Jones on the current state of the MetaCat OAI-PMH provider.
• Ryan: discuss with Matt Jones (and Mark?) how to ensure that we're implementing things in a way to will work well for other Metacat installations.
• Ryan: work with MRC to determine "ideal" Dryad records.
• Duane: Create XSL to convert EML -> simple DC.
• Duane: Create XSL to convert EML -> Dryad application profile.
• Duane: Create XSL to convert dryad application profile -> EML.
• Ryan: Evaluate quality of simple DC and Dryad application profile records, suggest modifications to XSL.
• Duane: Complete/create OAI-PMH provider functionality in LTER Metacat.
• Ryan: Configure harvest of Metacat metadata and test metadata availability in Dryad.
• Duane/Mark: Move OAI-PMH provider code from LTER to core Metacat.
• Duane: Install an OAI-PMH harvester at LTER and configure to harvest from the Dryad provider.

Open Questions

• Should any "sets" be defined in the provider? Is there any natural breakdown of the MetaCat data into categories?
• Is there any need to convert from simple DC to EML?
• UNM can send us the metacat XSL, so we can display EML "properly" if we want. Is there any reason Dryad should display the EML in a more Metacat-like manner?

EML Examples

The EML schema documents (EML 2.0.1) can be downloaded at http://knb.ecoinformatics.org/software/download.html#eml (note that there is a new revision, EML 2.1, of the schema due to be released this Spring).

1) Georgia Coastal Ecosystem LTER (knb-lter-gce.247.9.xml): Annual summaries of daily climatological observations from the National Weather Service weather station at Brunswick, Georgia for 1915 to 2004.

2) North Temperate Lake LTER (knb-lter-ntl.110.2): Lake Metabolism in North Temperate Lakes.

3) Andrews Experimental Forest LTER (knb-lter-and.3185.4.xml): Role of vegetation and coarse wood debris on soil processes and mycorrhizal mat distribution patterns at the Hi-15, Andrews Experimental Forest.

Data in EML that has no logical place in the Dryad Application Profile:

• description of dataset size, encoding, table format, implementation details
• details of fields within the dataset
• geographic bounding boxes
• processing method
• software
• author/organization distinction
• access control