- From: Sandro Hawke <sandro@w3.org>
- Date: Wed, 16 Mar 2011 21:54:03 -0400
- To: Thomas Steiner <tsteiner@google.com>
- Cc: RDF Working Group <public-rdf-wg@w3.org>
On Thu, 2011-03-17 at 00:20 +0100, Thomas Steiner wrote: > Hello all, > > While I love "GRDDL for JSON" as a name, I'm still not sure it is a > generalizable functionality that would be straight-forward to offer. > As I said today on IRC, isn't it one-offs for each and every single > JSON data provider? Isn't the objective of this WG to come up with > something that JSON data providers would use in the first place? We > can still provide (or document how to provide) > mappings/goggles/"GRDDL", but in my opinion this shouldn't be our > primary goal. Lots of questions to be discussed at the F2F or earlier. > Maybe I simply got the concept wrong, though. Thanks for corrections > in either case. Thinking about it, I'm seeing a spectrum of the folks who send data using JSON and their relationship to RDF and this effort. In order of least-RDF-friendly to most-RDF-friendly..... Level 1 - Folks who publish json data which cannot be easily mapped to RDF and are not willing to do anything about it. If a translator-to-RDF is done for their data, it will have to be complex (probably using a Turing Complete language ) and done without their participation. Level 2 - Folks who publish json data which has a fairly clean mapping to RDF (basically namespaces prefixes and property types), but are still not willing to do anything at all to help RDF consumers. Level 3 - Folks who are willing to help with the mapping, and have the mapping information served from their website in a way that machines can find. But they don't want non-RDF json users to see any hint of RDF in their actually data stream. Level 4 - Folks who are willing to add a few little flags to their json data, such as the URL of the mapping-to-RDF declaration. Level 5 - Folks who are willing to include all the necessary information for mapping their json to RDF, so their data can be converted without additional dereferences. This probably goes along with having a json data design that is close enough to RDF that the mapping is pretty trivial, so maybe they had to design their json a bit differently. Level 6 - Folks who are willing to make their main json feeds specifically designed for RDF compatibility, probably making their json seem a little odd to people with a feel for json. These are the folks that I think the charter requires us to address; it's debatable how much we should cater to levels 1-5. (I think helping levels 3-5 is desirable, but might not be practical. Level 7 - Folks who are willing to provide their data in RDFa, RDF/XML, or Turtle. These folks don't actually need us to do anything in the json space. I think there are also some different segments among developers (json users): Group A - Developers consuming data from a relatively small number of sites, willing to do custom coding for each site (eg hardcoding how to read news streams from twitter *and* facebook). These folks probably want very comfortable and obvious json they can use without libraries. That's what they get now, and they wont like the json to get messier. I don't think we can offer anything to this group; our job is avoid making their lives difficult or annoying them. Groups B+C - Developers who do not want to do custom coding per data source. They want to see those news streams in some common interface, so they don't need special code for each one. That sounds like RDF to me. (These developers are also working on behalf of users who don't want to hire more developers for each data site.) Now, this group can be divided into: -- Group B, Developers who want the generality of RDF but don't want to use any sort of RDF API. For them we could try to make a format the Level-6 producers will publish and which Group-B developers can consume without complex code or a library/API. -- Group C, Developers who want the generality of RDF, but are willing to use an RDF API. What they really need is for their libraries to support Level-N sources, for as low an N as possible. They would be most happy if they have RDF API access to even Level-1 sources, without having to do any work. (This could potentially be done with some sort of open repository of javascript modules which translate various publishers' json to RDF. I think level-3 is as low as this WG can go, though.) Looking at this matrix of 21 boxes (in my head), I'm seeing two sweet spots, where we could do some good: 6-B and 3/4/5/6-C. I'm worried that 6-B is over-constrained (anything we do will annoy Group A -- we went through this with RDF and XML), so I think our best bet is probably 3/4/5/6-C. At least, that's how it looks to me right now. This is the space of standardizing annotations, occurring inline or out-of-band, which enable deterministic, efficient conversation of "normal" json into RDF triples, by a library. Note that for this space (1) we don't need to serialize every kind of RDF graph, and (2) the json is "pretty" (but not RDFy) for Group-A folks, but can be converted by standard code, eventually built into various libraries, to RDF for Group-C folks. Group B may just be out of luck any way we slice it. -- Sandro > Best, > Tom > > Thank God not sent from a BlackBerry, but from my iPhone > > On 16.03.2011, at 23:27, Andy Seaborne <andy.seaborne@epimorphics.com> wrote: > > > > > > > On 16/03/11 17:07, David Wood wrote: > >> On Mar 16, 2011, at 10:59, Richard Cyganiak wrote: > >> > >>> On 16 Mar 2011, at 01:11, Manu Sporny wrote: > >>>> I know that Richard did a good job writing up an argument for a > >>>> triple-based serialization, but even the write-up wasn't a > >>>> glowing recommendation for that approach. > >>> > >>> Fair enough. > >>> > >>>> PROPOSAL: The RDF Working Group should design the RDF in JSON > >>>> syntax structure to reflect the object-based data model that is > >>>> in wide use in the Web developer community. The group recognizes > >>>> that both the triple-based and iterative-reduction based > >>>> approaches are useful and have a purpose to serve, but the time > >>>> it would take to standardize two RDF in JSON syntaxes may impact > >>>> the ability for the Working Group to meet its tight 1-year > >>>> deadline. > > > > The time argument only makes sense if you are talking about the same people swapping between the two extremes. From the discussions so far, that's far from clear to me. > > > >>> > >>> I'd prefer not having to vote on this proposal yet, because there > >>> are certain clarifications and discussions that I'd like to see > >>> before making up my mind. > >>> > >>> My concerns here are: > >>> > >>> 1. It appears to me that the goal of the RDF-in-JSON approach as > >>> championed by Manu is not to serialize an RDF graph in a JSON > >>> syntax, but to standardize a system of JSON conventions that allow > >>> parsing of the output of existing JSON APIs (perhaps with small > >>> modifications) as RDF. > > > > I agree. > > > > Sometimes it sounds more like "GRDDL for JSON". The mapping isn't universal - the generation of IRIs from data that has sufficiently unique keys is application dependent, for example. > > > >>> > >>> 2. If I am mistaken in thinking so, then I observe that a lot of > >>> Manu's arguments in favour of the object-based approach fall apart, > >>> especially those regarding �picking up the developers where they > >>> are right now.� > >>> > >>> 3. If my observation regarding the goal of this RDF-in-JSON > >>> approach is correct, then I think we need discussion about charter > >>> scope and WG composition, as the goal appears somewhat broader than > >>> what the WG was chartered for. > >> > >> Perhaps, but this seems like a reasonable conversation to have. > >> Let's get the proposal fully on the table and then take it off if we > >> need to (or coordinate with other groups as appropriate). > > > > Then the phrase "RDF in JSON" seems the wrong way round. It's "JSON as RDF". > > > > PROPOSAL: The RDF Working Group JSON Task Force will work on way of mapping typical existing JSON data objects into a form that can be interpreted as RDF. > > > > > > Feel free to suggest a better wording - this is just a quick draft to try to find a proposal that is about the core issue directly, and not indirectly by talking about syntax structure. > > > > Andy > > > >> > >> Regards, Dave > >> > >> > >> > >>> > >>> Best, Richard > >> > >> > > > >
Received on Thursday, 17 March 2011 01:54:14 UTC