Re: Some points in editor's draft that we might want to discuss our understandings of

John Arwe/Poughkeepsie/IBM@IBMUS wrote on 07/15/2013 05:52:40 PM:

> 4.1.10 LDPR servers MUST advertise their LDP support ... 
> During the F2F someone (Sandro maybe?) said that we should state 
> that the ldp:Resource link header is roughly equivalent to 
> rdf:type=ldp:Resource... at least that's how I interpreted what I 
> heard, and I reflected that in the draft using the "notionally 
> equivalent" language.

I think that pretty much matches the resolution, assuming this is what 
"shorthand" meant:

Closed, adding that LDP servers MUST advertise LDP with a link header: 
Link: <http://www.w3.org/ns/ldp/Resource>; rel=type (and noting that we 
consider rel=type to be shorthand for the rdf:type property). And 
we/others can subclass ldp:Resource as needed later.
See: http://www.w3.org/2013/meeting/ldp/2013-06-18#resolution_1 

>   It's chafing a bit - I don't think they are 
> in fact equivalent.  A non-LDPR server "dumb RDF store" might 
> happily serve up a document with rdf:type=ldp:Resource, and 
> *without* the header.  A client should not expect behaviors like 
> "must serve Turtle" from such an implementation, so they're clearly 
> not equivalent.  This counter-example in fact might illuminate 
> things in one of the accompanying documents. 

This is indeed the case and it's been pointed out before. This is the old 
story about the data model vs the interaction model. I'm not willing to 
rehash this point.

The spec is clear about the fact that the HTTP header is a MUST have and 
clients ought to be coded against that to be safe.

> ...

> Best Regards, John
> 
> Voice US 845-435-9470  BluePages 
> Tivoli OSLC Lead - Show me the Scenario 

Thanks.
--
Arnaud  Le Hors - Software Standards Architect - IBM Software Group