W3C home > Mailing lists > Public > public-ldp@w3.org > January 2014

Re: Multiple resource representations during LDPC POST (5.4.1)

From: (wrong string) čius <martynas@graphity.org>
Date: Wed, 22 Jan 2014 13:11:07 +0100
Message-ID: <CAE35VmxaNdEGR7fjV_-Fe0wQ4mqPRpTN-+iaow+Nz+RC43kziw@mail.gmail.com>
To: John Arwe <johnarwe@us.ibm.com>
Cc: "public-ldp@w3.org" <public-ldp@w3.org>
Hey John,

are you saying that it is more important for a Linked Data Platform to
support binary resources than to use existing terminology and build on
established RDF standards like SPARQL? The binary use case is far from
convincing to me.

You're right that I'm in trouble implementing PUT as my argument is
that you cannot store resource description in a single graph, by
*directly* submitting it to the resource URI. But that does not stop
me from storing those graphs indirectly (using GSP) and still
retrieving RDF representations of resources that are assembled from
multiple such graphs.

POST can be also implemented this way but there has to be a
correspondence between resources and graphs, such as "Graph per
resource" pattern:
http://patterns.dataincubator.org/book/graph-per-resource.html

Martynas

On Mon, Jan 13, 2014 at 4:14 PM, John Arwe <johnarwe@us.ibm.com> wrote:
>> as input -- but why call it "representation" as 5.4.1 does, and not
>> "graph"?
>
> Because 5.4.1 applies to creation of all types of members, not only of
> members representable as RDF.
> It's an HTTP interaction, and HTTP transfers representations (generally).
>
>> I'm arguing that one cannot PUT or POST a resource representation (in
>> full). One can only GET it, possibly as product of multiple graphs, as
>> with the DESCRIBE result.
>
> At the HTTP level, your PUT argument sounds equivalent to saying PUT cannot
> be implemented, which conflicts with implementation experience.
> You MIGHT be in similar trouble with POST, I have not checked 2616's wording
> today but generally it talks about POST accepting processing instructions
> (create is one example of that usage, but not the only one).
>
> If you are talking about some restricted subset of all Web resources,
> "maybe" [he says, without checking ;-) ].  But as soon as I wrote "Web", I
> started to feel like it will be a definitional issue.
>
>> I think "description of resource" from SPARQL is actually the true
>> meaning of LDP "resource representation", and defined better:
>
> That might be true if LDP 5.4.1 ONLY dealt with graphs, but that's not the
> case.  Search on "binary" for other points in the text where this comes out
> more clearly.
>
>
> Best Regards, John
>
> Voice US 845-435-9470  BluePages
> Tivoli OSLC Lead - Show me the Scenario
>
Received on Wednesday, 22 January 2014 12:11:34 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 20:03:11 UTC