The RDF mapping of the geoshape datatype is not correct yet. Geoshapes are currently represented as strings in RDF, instead of the URLs of the actual shape.
In RdfBuilder::propertyIsLink(), there is a hard-coded list of data types that should be treated as URLs. geoshapes Need to be added to the list.
Conceptually, geoshapes should be handled similarly to the commonsMedia types in the RDF mapping. This means we need a GeoShapeRdfBuilder similar to CommonsMediaRdfBuilder, and RdfVocabulary::getGeoShapeURI similar to RdfVocabulary::getCommonsURI (which should probably be renamed to getMediaURI).
According to T161527: RFC: Canonical data URLs for machine readable page content, the canonical URL for pages in the Data namespace on commons should have the following form:
See also the relevant design document.