harvest based distributed library index ?

[Tony Barry]

At 6:17 AM 19/6/97, <wawra at info.ub.uni-potsdam.de> wrote:
>has anyone seen/or used/or produced a harvest-based distributed index of
>library catalogues (opacs) ? we are thinking about a regional
>distributed library system which based on tools for gathering,
>extracting, searching, organizing and cache information.

Harvest needs replicable URLs to work.  I don't think it will work on
webopac sites that use POST forms as the search arguments are not passed in
the URL.

Harvest also normally also navigates down a tree and would stop at a form
or ISINDEX page. You therefore need some way for harvet to find the data.

I'm a bit familiar with Innopac wich uses ISINDEX but the URLs are only
stable done to the first level of search.  After that however they depend
on the current content of that search result. If an record has an ISBN or
ISSN there is a stable URL to it but no fixed path via the OPAC for Harvest
to follow.  You might be able to do it by cobbling together something in
harvest which probed the site for all possible ISSN/ISBN numbers recording
hits as it got them but it doesn't sound like a good idea.  Otherwise you
could export data from the OPAC for harvest to pick up but then you start
getting all the problems of a union catalgue.

Hope somebody else has some better ideas than I do as its a good concept.

There has recently been an amendment to the z39.50 specification which
would let a client update the local database and a union catalogue
simultaneously which is another possibility BUT I don't think there are and
clients yet which can do it.

Tony

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