W3C

RDF-star

9 April 2021

Attendees

Present
AndyS, gkellogg, james, ora, pchampin, rivettp, TallTed
Regrets
-
Chair
pchampin
Scribe
ora, pchampin

Meeting minutes

Announcements and newcomers

new member: Julián

pchampin: I will take some time off next week, will not be on next call

pchampin: who will be the chair?

pchampin: propose we skip next week

pchampin: new pull request from gkellogg

pchampin: Trig-star

gkellogg: still some questions to be worked out

gkellogg: e.g., ordering

pchampin: examples in abstract syntax is a good idea

andys: prefer Turtle* first

gkellogg: will do a PR for ordering

Action: gkellogg to reorder the concrete sections: Turtle-star, TriG-star, N-Triples-star, N-Quads-star

<Zakim> AndyS, you wanted to say that there is a TriX-star implementation (!!)

andys: I did a TriX-star implementation, for no reason whatsoever

<gkellogg> I updated my TriX implementation too :)

Open actions

pchampin: no open actions

publishing a new draft

<AndyS> The 2nd draft discussion -- https://w3c.github.io/rdf-star/Minutes/2021-03-19.html#t04

pchampin: canonicalization will probably not make it to the next draft

pchampin: we discussed that a new draft sooner rather than later would be a good thing

pchampin: publish often and early

pchampin: some things are pending...

pchampin: 5 PRs

pchampin: some have no impact on the draft

pchampin: test suite

<pchampin> https://github.com/w3c/rdf-star/pull/149

pchampin: does not stop us from publishing

(audio weirdness, did not capture everything...)

now fine again...

<pchampin> https://github.com/w3c/rdf-star/pull/129

pchampin: long standing PR: clarification of SPARQL functions

james: that's what I wanted to add

pchampin: olaf wanted to remove some examples

pchampin: recommend merging anyway

<pchampin> https://github.com/w3c/rdf-star/pull/155

pchampin: recent PR: extending the overview with examples using annotation syntax

pchampin: propose we leave a few days for people to react, merge next week

pchampin: after these merges we should publish

<pchampin> PROPOSAL: merge PR 129 and 155 after a few days, and then release next public draft

<pchampin> +1

<william> +1

<gkellogg> +1

<ora> +1

<james> +1

<rivettp> +1

<AndyS> +1

<TallTed> +1

<Julian> +1

pchampin: reminding we are not a formal group, wrt. voting

Resolution: merge PR 129 and 155 after a few days, and then release next public draft

andys: what is the most pressing issue to close?

pchampin: I will be back the week after next

pchampin: several active issues

pchampin: we are in pretty good shape overall

pchampin: but still: introducing a new IRI

pchampin: mime-type

pchampin: do we want to include something about SHACL, possible SHEX?

andys: I think no need to do that

andys: once there is a CG report (our target), then the SHACL group can react

andys: similarly for SHEX

gkellogg: we did not address JSON-LD either

andys: label open issues as "discussion items"...?

pchampin: Notation3, semantics (at least) belong there

<pchampin> STRAWPOLL: we won't include anything in our report about SHACL not SHEX

<gkellogg> +1

<william> +0

<james> +1

<ora> +1

<AndyS> +1 (better to come from those communities)

<Julian> +1

<rivettp> I think we should at least mention SHACL and OWL with an outline of possible impact

<pchampin> +1

<rivettp> -1

pchampin: I did not mean to not mention at all

pchampin: the idea is not to ignore, we can give some "leads"

rivettp: should be fine

<AndyS> FYI: OWL-star https://w3c.github.io/rdf-star/UCR/rdf-star-ucr.html#compact-serialization-of-owl-graphs -- from https://github.com/w3c/rdf-star/issues/148

<rivettp> +1

pchampin: next public draft is very close to a final report

pchampin: editorial changes notwithstanding

RDF-star and dataset canonicalization

pchampin: this was raised by gkellogg

pchampin: there is a W3C WG charter proposed, linked data signature

pchampin: standard way of signing RDF datasets

pchampin: hence canonicalization

pchampin: question was raised about RDF* during preparation

pchampin: RDF-star included in the proposed charter

pchampin: understanding that RDF-star will not be a Rec by then

(thank you AndyS)

pchampin: dataset defined in terms of triples, nothing about embedded triples

pchampin: clarification is needed

gkellogg: canonicalization is challenging (math proofs), extending to RDF-star could be problematic

gkellogg: RDF-star dataset transformed to RDF dataset could be signed

gkellogg: but now we would have two versions of the same

gkellogg: let's not use language that restricts our work too much

andys: how about a short section about principles (embedded triples, etc.), any future work on RDF will need to deal with these

andys: that is, set requirements rather than offering solutions

gkellogg: they may not heed any of that

gkellogg: solution may involve introduction of a new vocabulary

gkellogg: make it possible to do a reverse transformation

andys: RDF-star system understand embedded triples natively, this may be a problem

pchampin: hidden IRIs...

andys: my point was that they are not isomorphic

gkellogg: canonical does not have to imply isomorphic

andys: what if two different things have the same canonicalization, because we missed something?

andys: you may need to know that something was originally RDF-star

<gkellogg> Link to RDF C14N draft: https://json-ld.github.io/rdf-dataset-canonicalization/spec/

pchampin: introduce reification predicates only for this purpose?

pchampin: an RDF graph using these would be identified as coming from RDF-star

gkellogg: canonicalization algorithm should introduce extensible steps [?]

gkellogg: it is not our job to solve this, but make it possible for future groups to solve it

gkellogg: this is not simple to implement

gkellogg: math proof is required, changing the algorithm would invalidate the proof

andys: IRI spec explains how to turn an IRI into a URI

pchampin: what do we do after publishing the 2nd draft?

andys: mention it in the charter...

andys: we will not be recommending changes to the algorithm

gkellogg: similar to n3 and lists

pchampin: we will liaise at some point

pchampin: not much more we can do

pchampin: no time to discuss media type this time

open-ended discussion

gkellogg: namespace for hidden triples?

pchampin: type for hidden triples?

andys: new extension namespace for all groups to use

andys: "rdfx"

pchampin: temporary use?

andys: that is the idea, but reality may be different

andys: creating things is easy, getting rid of them not so much

pchampin: we could create a temporary RDF-star namespace, just as easy to fix (or not)

pchampin: put a time extent on these

<AndyS> e.g. https://w3.org/ns/rdfx

andys: what's under "ns" at W3C?

ora: I don't understand the need for that NS
… namespaces are cheap
… the essential thing is that they must be unique
… This notion of shared namespace is a misuse of the concept.
… It may create clashed, which namespaces were invented to prevent.

<rivettp> I think rdf namespaces are a mess because we have too many - people don't know when to use rdfs vs rdf

<william> yes, indeed

gkellogg: there is a difference between something that is eventually meant for, say, the RDF namespace, as opposed to something that remains separate

<william> thanks!

<gkellogg> We need a CG to discuss transitional IRIs :)

bye

Summary of action items

  1. gkellogg to reorder the concrete sections: Turtle-star, TriG-star, N-Triples-star, N-Quads-star

Summary of resolutions

  1. merge PR 129 and 155 after a few days, and then release next public draft
Minutes manually created (not a transcript), formatted by scribe.perl version 127 (Wed Dec 30 17:39:58 2020 UTC).