wrong semantic modeling in GS1DigitalLinkCompressionPrototype

[VladimirAlexiev]

Picking up from #33.
@mgh128 (cc @philarcher )
Notes on the semantic modeling implicit in https://gs1.github.io/GS1DigitalLinkCompressionPrototype/
I understand it's just a prototype but I'd rather speak up now than later.

• Go to last section and input this in GS1 Digital Link URI: http://example.org/01/05412345000013/21/ABC%26%2B123?7003=1903061658
• save as DL-example.jsonld
• convert to Turtle:

<http://example.org/01/05412345000013/21/ABC%26%2B123>
        rdf:type                schema:Product , owl:Class , gs1:Product , rdfs:Class ;
        rdfs:subClassOf         <http://example.org/01/05412345000013> ;
        dcterms:isPartOf        <http://example.org/01/05412345000013> ;
        schema:gtin             "05412345000013" ;
        owl:sameAs              "http://example.org/01/05412345000013/21/ABC%26%2B123?7003=1903061658" ;
        gs1:elementStrings      "(01)05412345000013(21)ABC&+123(7003)1903061658" ;
        gs1:expirationDateTime  "2019-03-06T16:58:00"^^xsd:dateTime ;
        gs1:gtin                "05412345000013" ;
        gs1:hasSerialNumber     "ABC&+123" .

1. Modeling Product (and ProductBatch) as RDF classes and using subClassOf is questionable
   • Will lead to an uncontrollable proliferation of classes
   • Will mix up the defined hierarchy (eg gs1:WearableProduct<gs1:Product) with these uncontrolled classes
   • Goes against schema.org practice
   • Is certainly wrong for the above thing which is an IndividualProduct (because it hasSerialNumber)
2. I also don't quite like dct:isPartOf. I think it's better to use specific props. Eg I've used schema:model, but maybe a new gs1:product is better:

<$SGTIN_PRODUCT1> a gs1:IndividualProduct;
  schema:model <$GTIN_PRODUCT1>;
  gs1:gtin "$GTIN1";
  gs1:hasSerialNumber "$SERIAL1".
<$LGTIN_PRODUCT2> a gs1:ProductBatch;
  schema:model <$GTIN_PRODUCT2>;
  gs1:gtin "$GTIN2";
  gs1:hasBatchLotNumber "$LOT2".
<$GTIN_PRODUCT1> a gs1:Product;
  gs1:gtin "$GTIN1".
<$GTIN_PRODUCT2> a gs1:Product;
  gs1:gtin "$GTIN2".

4. owl:sameAs is not declared @id, that's why it's value is a string but must be a resource (URL)
5. Using sameAs means that a Product/Batch/Individual with extra details is the same as the basic thing without these details, therefore it is an error to use the same GTIN/LGTIN/SGTIN with different sets of details.

<http://example.org/01/05412345000013/21/ABC%26%2B123>
        owl:sameAs   <http://example.org/01/05412345000013/21/ABC%26%2B123?7003=1903061658>;
        owl:sameAs   <http://example.org/01/05412345000013/21/ABC%26%2B123?7003=2103061658>. ## error