VOSpace vs WebDAV

[Markus Demleitner]

Hi GWS, Hi Registry,

[Followups, I guess, should only go to registry at ivoa.net]

For Registry folks not on GWS:  There's been a discussion on
the relation between various URI schemes and http over on the GWS
mailing list, with this contribution from Norman:

http://www.ivoa.net/pipermail/grid/2014-May/002587.html

To this and a previous mail from yours truly, Dave replied:

On Thu, May 15, 2014 at 10:22:56PM +0100, Dave Morris wrote:
> 
> On 2014-05-15 13:20, Markus Demleitner wrote:
> >
> >.... and frankly I think plain HTTP
> >(in the sense of "curl is all you need") just won't do as a Registry
> >client protocol, even with accept: and all the other fancy stuff.
> >
> 
> Actually ... Norman's description of the ARK service got me thinking.
> I agree with Paul, Norman is probably right about many things and we
> should listen to him more often ;-)
> 
> For a registry resolver service, all we want it to do is to resolve
> an 'ivo://' URI into the corresponding VOResource document.
> 
> So, could we define a 'RegistryResolver' service as a web server
> where you add an 'ivo://' URI to the RegistryResolver endpoint, and
> you get back the corresponding VOResource document, or a 404 error.
> 
> Nothing more than that.
> No resource discovery.
> No query language, table formats or schema.
> No partial fragments or subsections of the document.
> 
> Just the VOResource XML or a 404 error.

OAI-PMH isn't very far from this.  But I give you that simple URLs
matter, so I sat down and quickly wrote an NMAH for ivo; this is a
quick hack and probably has wires sticking out left and right, but if
anyone wants to experiment, it's there.  Try, e.g.,

http://dc.g-vo.org/rr/q/nmah/custom/ivo://cds.vizier/j/a+as/58/39
http://dc.g-vo.org/rr/q/nmah/custom/ivo://archive.stsci.edu/borg
or
http://dc.g-vo.org/rr/q/nmah/custom/ivo://org.gavo.dc/__system__/tap/run

Given this is fairly straightforward, I could well imagine having it
in RI2 -- as usual, XML namespaces and their prefix mappings are
tricky to get right, but if you run OAI-PMH (which we'll keep
requiring, I expect) on harvested records, you need to handle those
anyway.

In short: I like it.  A much easier sell than
...?verb=GetRecord&metadataPrefix=ivo_vor&identifier=...

Cheers,

        Markus