HEASARC registry metadata and simple publishing protocols

[Thomas McGlynn]

Jeongin has been working building the metadata for the HEASARC tables
that will go in a registry.  For the moment, we're thinking that
the HEASARC will not have an active, does-everything registry, we'll
simply provide the documentation on our datasets for inclusion in
other registries.  Probably we'll do more in the future.

Jeongin has created something like 300 XML descriptions as separate files.
Does anyone have any experience going from there to building an OAI
interface that allows others to harvest these descriptions?  E.g.,
as I understand the OAI interface, it basically allows a harvester to
ask for anything that has been updated since a given date.
I'm wondering if something as simple as a shell script like

     cat OAIHeader > output
     find xmlDirectory -mtime $time exec cat {} \>\> output \;
     cat OAITrailer >> output
     cat output

where we just concatenate all the entries that have been modified since the
date the user has requested might satisfy the OAI harvesters.  Of course
we'd need to parse the CGI arguments and such too.  Is there anything
else we need to do to be OAI compliant?  If we can really do this with
very simple software it will be a real encouragement for others to publish
their metadata.

It will be a couple of weeks before we're ready to publish these tables -- they
are under internal review -- but pointers to simple OAI implementations
would be welcome.

	Thanks,
	Tom McGlynn