I’m porting Geonetwork’s CSW client from Java to .NET. {I really like Java 1.5+ enums, BTW, very cool.}
I’m not about to brag about my methodology : I try to compile, it complains, I fix where it complained.
The relief is that I started with 650+ errors, and now I have zero compile-time errors to go.
Tons of runtime errors… but zero compile-time errors!
I’ve been hunting decent Catalogue Service clients. I want to use one in my web applications, and if I’m going to put any work into it, I’d like to be able to reuse it as an ArcMap plugin. Now, ESRI’s got their own, closed-source Portal Toolbar. However, my initial assessment says it has no soul; it relies on ESRI’s metadata shortcut nodes. Not cool, not extensible, and not useful as a library for my web applications.
I did find a couple of FOSS CSW clients… one from Deegree (LGPL‘ed), and one from GeoNetwork Opensource (GPL‘ed). To make a long story short, the Deegree one isn’t going to work. So I’ve strapped on my scuba gear, and begun the descent into the world of the GPL.
Now, the GPL FAQ tells me that I can modify GeoNetwork’s code however I want, as long as I don’t share it. I’m assuming that means I’m allowed to modify it for my web applications. Dive much deeper than this, and the barotrauma starts to kick in. I can’t distributed code that links closed-source libraries (ArcGIS’s) with GPL’ed libraries. Okay… but where do you draw the line on what’s considered linking?
Its entirely reasonable to use GeoNetwork’s GPL’ed CSW client to call a closed-source CSW server. Can I interpret this to mean that an XML web service is enough to differentiate between the GPL’s concepts of bundled programs and combined modules? So, what, I expose my server-side, modified, GPL’ed CSW client to ArcMap via SOAP? That doesn’t exactly make me feel happy technology-wise, and violates the spirit of the GPL.
To the point, I’m hoping some OS-GIS people out there will help me do a very bad thing. I’m hoping GeoNetwork’s CSW client can swim to more pleasant LGPL waters {minus some GPL’ed dependencies}. I’ve previously made ESRI-kool-aid inspired comments that OS-GIS needs more ArcGIS plug-ins to subvert ESRI users. I’m not sure GPL’ed clients are going to get us there.
Comments? Any GeoNetwork people out there?
UPDATE:
Paul Ramsey says fear not! The GPL’s code-mixing considerations shouldn’t affect me, see the comments for details.
I’ll keep this one short and sweet. There are some interesting open-source CSW (Catalogue Service for the Web) server options. Can anyone point me to open-source OGC CSW clients?
UPDATE:
http://geonetwork-opensource.org/ Version 2.1 (in Beta) will come with both server and client support for CSW. You can head over to http://sourceforge.net/projects/geonetwork and grab it today. The only caveat is that its GPL’ed … which doesn’t make distributing ESRI+CSW binary plugins feasible.
Deegree also has a client, in the org\deegree_impl\clients\wcasclient branch. The advantage of it is that its LGPL. The disadvantage is that (I have no idea how to run it and) it has a class named “AddToShoppingCartListener.” Forgive me for not knowing how that pertains to a Catalogue Service.
