W3C home > Mailing lists > Public > public-vocabs@w3.org > March 2014

Re: schema.org Roles design

From: Jarno van Driel <jarno@quantumspork.nl>
Date: Wed, 26 Mar 2014 23:21:33 +0100
Message-ID: <CAFQgrbYrRXGWnwh5394gjDyyxDS7ZvmDMVzMrNV_YhRZFsbd3Q@mail.gmail.com>
To: Aaron Bradley <aaranged@gmail.com>
Cc: Dan Brickley <danbri@google.com>, Jason Douglas <jasondouglas@google.com>, Guha <guha@google.com>, Gregg Kellogg <gregg@greggkellogg.net>, W3C Web Schemas Task Force <public-vocabs@w3.org>
Just to make sure I got it right (or wrong), I've had a try add translating
it to Microdata. Is this correct?

<div itemscope itemtype="http://schema.org/Movie">
<span itemprop="name">Ghostbusters</span>
<span itemprop="hasRole" itemid="movierole_678" itemscope itemtype="
http://schema.org/MovieRole">
<span itemprop="characterName">Dr. Peter Venkman</span>
<span itemprop="actor" itemscope itemtype="http://schema.org/Person">
<span itemprop="name">Bill Muray</span>
<link itemprop="hasRole" href="movierole_678">
</span>
</span>
<div>


On Wed, Mar 26, 2014 at 10:55 PM, Aaron Bradley <aaranged@gmail.com> wrote:

> I'm baffled by @id as well.  Forget the RDFa/microdata/JSON-LD syntax
> differences for a moment, I've read the proposal but still don't know from
> whence the the @id values arise.
>
> In the PDF where does...
> @id "role321" come from? (e.g.1)
> @id "movierole_678" come from? (e.g. 2)
> @id "edurole25151" come from? (e.g. 3)
>
> Are these arbitrarily assigned by the coder?  Are these serial?  And are
> they resolvable to an IRI?
>
> And are they integral to the Role/hasRole proposal - that is, does
> everything break if they're not employed?  Am I correct in reading @ID in
> e.g. 1 ("role321") is the necessary entity referred to in order to have the
> "athlete property applied to the Role, instead of to a Team"?
>
> Now returning to the syntax, I'd certainly I'd love to see any one of
> these marked up with microdata. :)
>
> > it is important to find the right
> > balance between ease of adoption for publishers, expressivity, ease of
> > processing etc.
>
> I appreciate the perseverance of list members.  While my technical
> expertise is limited I'm no slouch either, and Jarno ain't a slouch at all
> - so if @id/@id-like functionality is crucial here it does have
> implications for the "ease of adoption for publishers".
>
>
>
> On Wed, Mar 26, 2014 at 2:22 PM, Dan Brickley <danbri@google.com> wrote:
>
>> On 26 March 2014 20:59, Jarno van Driel <jarno@quantumspork.nl> wrote:
>> > Well if @id has the same role as 'itemref' then could there also please
>> be
>> > some info explaining how that works, because to be honest, I sort of
>> > understand the proposal but am confused about @id/itemid. e.g. to me it
>> > seems @id functions the same way as @resource does in RDFa, or at least
>> > that's how I read it.
>>
>> The following are all similar in RDF-based languages - they identify
>> the entities being described:
>>
>> RDF/XML: about= (for subjects, i.e. the thing that has the property),
>> resource= (for objects, i.e. a thing that is a value of some property)
>> RDFa 1.0: about= (for subjects), resource= (for objects),
>> http://www.w3.org/TR/2008/REC-rdfa-syntax-20081014/#rdfa-attributes
>> RDFa 1.1: about= (for subjects), resource= (for objects),
>> http://www.w3.org/TR/rdfa-syntax/#A-about
>> http://www.w3.org/TR/rdfa-syntax/#A-resource
>> RDFa 1.1 Lite ... doesn't make this distinction; resource= works for
>> either . http://www.w3.org/TR/rdfa-lite/#resource
>> JSON-LD: @id http://www.w3.org/TR/json-ld/#node-identifiers
>> Microdata: itemid=
>>
>> http://www.whatwg.org/specs/web-apps/current-work/multipage/microdata.html#global-identifiers-for-items
>>
>> Most of these also have a way of using less-than-global local
>> identifiers too, as a way of joining up a graph structure from
>> different trees of markup. Microdata's itemref can also sometimes be
>> used for that purpose but as already discussed it is a different kind
>> of mechanism.
>>
>> > Wouldn't the Person linking back to the AmericanFootballRole create an
>> infinite loop?
>>
>> This is no more problematic than someone being their mother's son.
>> These languages are all oriented towards describing relationships; it
>> is natural that sometimes there will be loops.
>>
>> Dan
>>
>>
>
Received on Wednesday, 26 March 2014 22:22:01 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:29:38 UTC