Re: shapes-ISSUE-86 (dimitris): Associating shapes with ontologies or vocabularies [SHACL Spec]

On Thu, Oct 1, 2015 at 11:49 PM, Holger Knublauch <holger@topquadrant.com>
wrote:

> On 10/1/15 5:04 PM, Dimitris Kontokostas wrote:
>
> Now that it is more clear I would like to propose my resolution of
> issue-86.
>
> I suggest the spec mentions something in the lines of the following
> sentence
> ontology or vocabulary designers that want to publish SHACL constraints
> along with their schemas are encouraged (or SHOULD) either define the
> associated shapes in the same document with the schema or link to them
> through the sh:shapesGraph property.
>
>
> sh:shapesGraph would not have the right effect. It would basically only
> say that the ontology (e.g. definition of skos:Concept) itself would have
> to follow the shape definitions. I believe it should be owl:imports instead.
>

owl:imports and inline declaration have the exact same effect. the problem
with those is that if a user imports an ontology in the data graph, she
automatically loads the shapes as well which might not be what the user
expects / wants.

I agree that sh:shapesGraph does not have the exact semantics in this case
but when the ontology is loaded in the data graph, sh:shapesGraph gets
proper semantics again.
We can redefine the semantics of sh:shapesGraph or introduce a new property
for this


> Overall, I don't think we need to specify or recommend anything here.
> There will be different design patterns emerging, and we cannot anticipate
> yet which variation people will prefer, how SHACL will relate to OWL etc.
>

If we do not recommend anything we are forcing people to write shapes
inline or use owl:imports which might have an undesired effect.
I am ok with that, although I would prefer to have an alternative.

Dimtiris


>
>
> Holger
>
>
>
>
> This is independent of Peter's suggestion and if the WG thinks that
> Peter's suggestion should also exist in the spec I would vote +1 on this as
> well.
>
> Dimitris
>
> On Thu, Oct 1, 2015 at 8:43 AM, Dimitris Kontokostas <
> <kontokostas@informatik.uni-leipzig.de>
> kontokostas@informatik.uni-leipzig.de> wrote:
>
>>
>>
>> On Thu, Oct 1, 2015 at 5:35 AM, Peter F. Patel-Schneider <
>> pfpschneider@gmail.com> wrote:
>>
>>> I do not see that SHACL needs any connection between a shapes graph and
>>> an
>>> ontology definition.
>>>
>>> For purposes of designing a collection of shapes, having access to an
>>> ontology
>>> that provides axioms about the classes in a collection of shapes is
>>> handy.
>>> However, validating SHACL shapes or documents against a data graph or
>>> node in
>>> a data graph does not need any link going from the shapes graph to an
>>> ontology
>>> graph.   A SHACL validation engine does need to have access to ontology
>>> axioms
>>> to determine whether a node in the data graph is a SHACL instance of a
>>> class,
>>> but this is best done by including a graph with the required ontology
>>> axioms
>>> into the data graph.
>>>
>>> I therefore vote 0 for a) and -1 for the other options.
>>>
>>
>> Peter,
>>
>> I also do not think that shacl needs a link to an ontology/vocabulary.
>> The issue subject is indeed not clear but the intent was about the
>> reverse relation: ontology/vocabulary to shacl
>>
>> e.g. skos could define their additional constraints [1] in shacl and my
>> issue was about how could e.g. skos publish these constraints
>>
>> Dimitris
>>
>> [1] http://www.w3.org/TR/2009/REC-skos-reference-20090818/#L2422
>>
>>
>>>
>>> I would vote +1 for a proposal like:
>>>
>>> PROPOSED: The SHACL spec states that there is no need for a link from a
>>> SHACL
>>> shapes graph to an ontology graph and does not define such a link.  The
>>> SHACL
>>> spec further states that there is nothing in SHACL to prevent a SHACL
>>> shapes
>>> graph from including ontology axioms or importing ontology axioms, but
>>> that
>>> such inclusion or importation has no effect on determining whether a
>>> node in a
>>> data graph is a SHACL instance of a class.  The SHACL spec states that
>>> ontology axioms that affect SHACL are either part of the data graph or
>>> included from the data graph.   The SHACL spec mentions that SHACL shape
>>> graphs are often best developed in conjunction with a set of ontology
>>> axioms
>>> and that tools for the development of SHACL shapes may want to provide
>>> mechanisms for viewing axioms from a separate ontology.
>>>
>>> This proposal clearly makes the required distinction between what is
>>> required
>>> for SHACL validation and thus should be part of the SHACL language, and
>>> what
>>> is useful for SHACL development and thus should not be part of the SHACL
>>> language.
>>>
>>>
>>> peter
>>>
>>>
>>> On 09/10/2015 01:09 AM, RDF Data Shapes Working Group Issue Tracker
>>> wrote:
>>> > shapes-ISSUE-86 (dimitris): Associating shapes with ontologies or
>>> vocabularies [SHACL Spec]
>>> >
>>> > http://www.w3.org/2014/data-shapes/track/issues/86
>>> >
>>> > Raised by: Dimitris Kontokostas
>>> > On product: SHACL Spec
>>> >
>>> > Related to ISSUE-44, this is issue is about ways to associate an
>>> ontology or vocabulary to a set of shapes.
>>> >
>>> > Possible ways to resolve it
>>> > a) SHACL spec says nothing about associating ontologies/vocabularies
>>> with shapes
>>> > b) SHACL spec suggests the use of owl:imports
>>> > c) SHACL spec suggests the use of sh:shapesGraph
>>> > d) SHACL spec suggests shapes are defined in the same file with the
>>> ontology/vocabulary
>>> > e) SHACL spec suggests a combination of (d) with (b) or (c)
>>> >
>>> >
>>> >
>>>
>>>
>>
>>
>> --
>> Dimitris Kontokostas
>> Department of Computer Science, University of Leipzig & DBpedia
>> Association
>> Projects: <http://dbpedia.org>http://dbpedia.org, http://
>> http://aligned-project.eu, http://rdfunit.aksw.org
>> Homepage: <http://aksw.org/DimitrisKontokostas>
>> http://aksw.org/DimitrisKontokostas
>> Research Group: <http://aksw.org>http://aksw.org
>>
>>
>
>
> --
> Dimitris Kontokostas
> Department of Computer Science, University of Leipzig & DBpedia
> Association
> Projects: <http://dbpedia.org>http://dbpedia.org, http://
> <http://aligned-project.eu>http://aligned-project.eu,
> http://rdfunit.aksw.org
> Homepage: <http://aksw.org/DimitrisKontokostas>
> http://aksw.org/DimitrisKontokostas
> Research Group: <http://aksw.org>http://aksw.org
>
>
>


-- 
Dimitris Kontokostas
Department of Computer Science, University of Leipzig & DBpedia Association
Projects: http://dbpedia.org, http://http://aligned-project.eu,
http://rdfunit.aksw.org
Homepage:http://aksw.org/DimitrisKontokostas
Research Group: http://aksw.org