- From: Holger Knublauch <holger@topquadrant.com>
- Date: Fri, 25 Jul 2014 16:49:27 +1000
- To: "public-rdf-shapes@w3.org" <public-rdf-shapes@w3.org>
- CC: ryman@ca.ibm.com
- Message-ID: <53D1FDF7.7040304@topquadrant.com>
Dear RDF Shapes list, as a proof-of-concept, I have taken the OSLC Resource Shapes submission [1] and implemented it using SPIN. I believe this demonstrates nicely that SPIN and Resource Shapes are *complementary* technologies, and that Shapes can be implemented as one "instance" of the SPIN constraint language. This combines the beauty of a high-level vocabulary with the flexibility of a SPARQL-based fall-back mechanism. It works today, and the Shapes have proper executable semantics. The actual OSLC vocabulary and its SPIN constraint templates can be found at [2]. I took the little bug database example from the spec and implemented it using two different approaches: 1) [3] is syntactically almost identical to the OSLC example from [5] (only that it uses spin:constraint instead of oslc:property). For this version I had to tweak the current SPIN engine a bit so that it also executes "inherited" spin:body queries. I plan to add this tweak to future SPIN API (and TopBraid) versions. Here is an example snippet in Turtle: oslc_cm:ChangeRequest spin:constraint <http://example.com/shape/oslc-change-request#dcterms-title> ; spin:constraint <http://example.com/shape/oslc-change-request#oslc_cm-status> . <http://example.com/shape/oslc-change-request#dcterms-title> rdf:type oslc:Property ; oslc:name "title"^^xsd:string ; oslc:occurs oslc:Exactly-one ; oslc:propertyDefinition dcterms:title . <http://example.com/shape/oslc-change-request#oslc_cm-status> rdf:type oslc:Property ; oslc:allowedValues oslc_cm:status-allowed-values ; oslc:name "status"^^xsd:string ; oslc:occurs oslc:Zero-or-one ; oslc:propertyDefinition oslc_cm:status . 2) [4] is using individual bnode constraints instead of the "bundle" oslc:Property. You can load that version into the current SPIN API version, or into TopBraid Composer Free Edition 4.4. Navigate to <http://example.com/bugs/2> and press the "Display constraint violation warnings" button in the toolbar. It will display a small warning symbol with information on the actual violation. You can make edits and see the violations updated in real time. It "just works". Other shape libraries beside the specific OSLC version can be implemented in a similar manner. Regards, Holger [1] http://www.w3.org/Submission/2014/SUBM-shapes-20140211/ [2] http://knublauch.com/oslc/oslc.spin.ttl [3] http://knublauch.com/oslc/oslc_cm1.ttl [4] http://knublauch.com/oslc/oslc_cm2.ttl [5] http://www.w3.org/Submission/2014/SUBM-shapes-20140211/#examples
Received on Friday, 25 July 2014 06:50:56 UTC