<p>Tom Kralidis wrote Friday, August 04, 2006 3:23 PM <br>> Following the discussions on cataloguing, it may be a good idea outline<br>> what we would want a catalogue to do.<br>> <br>> 1./ discover the existence of a web service
<br>> 2./ discover the existence of a resource which is available via web<br>> services (i.e WMS layer, WFS feature type)<br>> 3./ discover the existence of a static resource (dataset, document,<br>> etc.)
<br>> 4./ ability to performs operations 1 - 3 with spatial, aspatial and<br>> temporal predicates<br>> 5./ provide a RESTful request API<br>> 6./ provide responses in XML</p>
<p>To me it's all this except perhaps 4. because the operations should concentrate on (incremental) 'harvesting' rather than distributed online querying. Security, as Norman Barker suggested, is solved otherwise and has been discussed in debates about RESTful services and security.
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<p>Having said that: I speak about 'search service' and to me such a web service has to important 'interfaces' one to the user and a programmatic one to the internet (besides internal persistence layers etc.).</p>
<p>Paul and others strongly emphasized to start with the focus on what users are probably looking for. To me they look for decisions and want to have access to information which is spatially related (sic: 'Open Access' and OAI). They are not looking for data per se and also not for services but for the map information behind them.
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<p>On the other hand we have spatial data providers as well as a community, like us (not actually the same as the data providers) who calls for open and better access to this geodata. What seems now crucial, is what have the geodata providers to do such that their information can be 'discovered' and hopefully bound automatically to users seeking geospatial decisions.
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<p>So to me the big challenge is now, to define what minimal information data providers should document as metadata and how they could publish it, so that spiders and registries can find, register and publish it as catalogues, specialized search engines for the deep web or build in geodata discovery components (as
p.ex. in uDig).</p>
<p>-- Stefan</p>
<p>BTW: I could transfer my stuff here<br><a href="http://www.geometa.info/rappiinfo/wiki/index.php/OSGeodata">http://www.geometa.info/rappiinfo/wiki/index.php/OSGeodata</a><br>to <a href="http://wiki.osgeo.org/index.php/Geodata_Metadata_Requirements#Discovery">
http://wiki.osgeo.org/index.php/Geodata_Metadata_Requirements#Discovery</a> (but I would open an extra page there)?</p>