Re: DESCRIBE ENDPOINT

On 30 Jun 2009, at 18:23, Axel Polleres wrote:

> Paul Gearon wrote:
>> On Tue, Jun 30, 2009 at 10:05 AM, Axel Polleres<axel.polleres@deri.org 
>> > wrote:
>> > just to pick up the discussion on "option 6" in today's telecon  
>> which was
>> > mentioned in a rush in the end of the telecon...
>> >
>> > I didn't get clear how
>> >
>> > DESCRIBE ENDPOINT
>> > or
>> > SELFDESCRIBE
>> >
>> > are different from
>> >
>> > DESCRIBE <endpoint-URI>
>> >
>> > Can someone elaborate?
>> A service may not necessarily know it's own endpoint URI so the  
>> latter
>> may not be possible. That's also why Steve raised the issue of
>> relative URIs.

In general, it's not actually possible. Especially in enterprise  
environments servers are often covered with 1:1 NAT policies as part  
of the security.

> So that could be DESCRIBE <.>


<> Might be more conventional. That depends on what BASE defaults to  
though. It will still map to some graph inside the store, which  
restricts the things you can import into the store without confusing  
the discovery.

>> On a slightly separate note, the "DESCRIBE <endpoint-URI>" form may  
>> be
>> capable of referring to descriptions on other endpoints. May that's
>> something we want to consider (or to exclude).
>
> yeah, that makes it look appealing somehow.

On the downside, you have to know that the endpoint speaks SPARQL  
before you can ask that query with any expectation of getting a  
sensible response.

With a HTTP header based method however, we can provide both forward  
and backward compatibility.

- Steve

-- 
Steve Harris
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Received on Tuesday, 30 June 2009 20:59:21 UTC