On 1/13/11 1:16 PM, Nathan wrote:
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.
Yes, maybe, but that takes time. The practical thing is to work with
what exists first, then finesse later. WWW already works this way. In a
sense, the real ingenuity of the WWW is the fact that imperfection is an
intrinsic feature :-)
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)
See comments above. That's InterWeb reality.
What needs fixing is Identity. Basically, what's happening via WebID
which is a great example of Linked Data exploitation.
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..
But it ain't going to happen within realistic timeframes, if at all.
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)
I think it should ask for data in a representation it understands as
defined by its application senses. If the server can't produce what is
required, the client should make a best effort to transform the data,
and if it can't do that, move on.
Perfection has never boostrapped anything. Pragmatism wins all the time.
WWW is a contemporary example of the aforementioned statement.
At this juncture, the goal has to be: Linked Data comprehension and mass
exploitation. It has to be inclusive and devoid of distractions. Those
who understand its nuances and innards should express these prowess via
their solutions -- client or server side. Every new productive Linked
Data solution -- that appreciate working with what exists -- simply
enhances the ecosystem.
Kingsley
Best,
Nathan
--
Regards,
Kingsley Idehen
President& CEO
OpenLink Software
Web: http://www.openlinksw.com
Weblog: http://www.openlinksw.com/blog/~kidehen
Twitter/Identi.ca: kidehen
