Kingsley Idehen wrote:
On 1/13/11 12:04 PM, Nathan wrote:
Hi Kinglsey,
Kingsley Idehen wrote:
When our engine describes entities it can publish these descriptions
using variety of structured data formats that include RDF. The same
thing applies on the data consumption side. Basically, RDF formats
are options re. Linked Data (the concept).
A generic problem here, when using non RDF types with Linked Data over
HTTP, is that there's currently no way to indicate that a resource
is/has a set of machine readable "linked data" variants, in many cases
it is useful to publish and consume with linked data in CSV format and
related (as you well note) - but without prior out of band knowledge
that the representation contains, or is, linked data, the machines are
pretty much screwed. Typically the RDF variants don't have this
problem because the media type sets the expectation, so you can conneg
on an RDF type and know your getting back "linked data", you can't do
this with CSV and related with any expectation that you'll get back
"linked data" - thus, if there was some way to mark the set of
representations given upon dereferencing a URI as linked data,
containing rdf, rdfable 3 tuples, or a view thereof, it'd be a lot
friendlier to the web of data in general.
So what happens to RDFa in (X)HTML? Even worse, no DOCTYPE declarations?
What about various JSON dialects for Linked Data graphs?
How about N-Triples? Ditto TriX and others?
Probably wasn't clear, I'm saying there needs to be something (for
instance a new header) which indicates that the representation contains
"linked data", then you machines could automatically throw the CSV
through a csv-linked-data parser and it'd work, likewise every type you
mentioned above.
The problem here isn't the different types of media, the problem here is
(1) internet media types are dire and badly need re-looked at
(2) there's no information provided to machine so that it has a hope in
hell of understanding one of these other variants (lest it has it's own
special mediatype)
Fix that and the door is opened to all of the above.
- RDFa needs an indicator at HTTP Message level to say it's "html+rdfa"
- JSON dialects need standardized (coming soon to a WG near you) w/
media type registered / well-known
- N-Triples needs it's own media type (doesn't have one)
- and so on..
Typically we need a machine to not only ask "Accept: something/rdf" but
to effectively ask "if linked data give me JSON" (swap json for csv,
turtle, rdf+xml, whatever)
Best,
Nathan
