- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Tue, 28 Jul 2015 19:49:15 -0400
- To: Holger Knublauch <holger@topquadrant.com>
- Cc: RDF Data Shapes Working Group <public-data-shapes-wg@w3.org>
* Holger Knublauch <holger@topquadrant.com> [2015-07-28 09:27+1000] > Both tickets [1] and [2] essentially talk about the same thing - how > a SHACL engine selects which shapes apply to a given data graph. My > proposal is to resolve both as follows: > > The SHACL engine is invoked with two parameters: > 1) a dataset including the data graph as its default graph > 2) a shapes graph (we don't need to decide on whether that must be > in the dataset here) In my experience, the most common question is "does this node conform to this shape?" This requires a schema and access to the data graph. Access to a node graph seems to be a requirement for SPARQL template implementations of SHACL. > There is a class sh:Graph, instances of which can represent the > named graphs themselves similar to owl:Ontology, but the use of > sh:Graph is not mandatory. Graphs that wish to help an engine find > its default shapes graph can use the property sh:shapesGraph in a > triple such as > > <dataGraph> sh:shapesGraph <shapesGraph> > > to point at one or more shapes graph - the union of those becomes > the input 2) unless specified otherwise. If the SHACL core > vocabulary is needed then it could look like > > <dataGraph> a sh:Graph ; > sh:shapesGraph <http://www.w3.org/ns/shacl> . > > In addition, graphs can point to each other using a property > sh:include, which plays a similar role like owl:imports, only > without the OWL dependency/ballast. It defines an imports closure of > graphs, e.g. myGraph sh:include schema.org to help tools such as > SHACL editors figure out which other files need to be loaded when > the user opens the base graph. > > Holger > > [1] http://www.w3.org/2014/data-shapes/track/issues/3 > [2] http://www.w3.org/2014/data-shapes/track/issues/44 > -- -ericP office: +1.617.599.3509 mobile: +33.6.80.80.35.59 (eric@w3.org) Feel free to forward this message to any list for any purpose other than email address distribution. There are subtle nuances encoded in font variation and clever layout which can only be seen by printing this message on high-clay paper.
Received on Tuesday, 28 July 2015 23:49:20 UTC