Status of this document
This report describes the current status of work on the RDF representation of records served by the Re3gistry and the INSPIRE Registry.
This specification is still work in progress, and it must be considered as unstable until the publication of its final version.
Summary
The data schema of the content of the Re3gistry consists of 4 main entities, depicted in the following diagram:
The registry is the service, whereas entitites register and item denote how the content served by the registry is organised. As shown in the diagram, items may include other items (referred to as child items). This is, e.g., the case of code lists, which are modelled as items, and code values, which are child items of code lists.
Entity item class is meant to denote the type of content corresponding to an item. Version 4 of the INSPIRE Registry includes the following ones: i.e., application schemas, (metadata) code lists, documents, feature concepts, glossary items, themes.
The proposed approach is as follows:
- The W3C Data Catalog vocabulary (DCAT) is used to model entities registry (
dcat:Catalog) and register (dcat:Dataset) - The Provenance Vocabulary is used to mode entity item (
prv:DataItem) - The W3C Simple Knowledge Organization System (SKOS) to model entity item class (
skos:Concept, orskos:ConceptSchemewhen an item has child items), with the only exception of the item class concerning reference documents, where the Friend of a Friend vocabulary (FOAF) is used instead (foaf:Document).
| NOTE | About item classes, it is to be considered whether to use other vocabularies in addition to SKOS. The mapping tables in the following sections include some proposals (marked with "?"- question mark). |
|---|
The adopted vocabularies determine also the properties used to model the relationships linking the different entities:
dcat:dataset: links the registry to registersdct:hasPart: links a register to an item, and an item to a child itemskos:inScheme: links any item modelled as askos:ConceptSchemeto its child items, which are modelled asskos:Concept's
In case of items organised hierarchically (e.g., some of the code lists), the proposed approach is as follows:
- 1st-level items are modelled as
skos:ConceptScheme's and all the rest are modelled asskos:Concept's skos:topConceptOfis used to link the 2nd-level items to the corresponding parentskos:hasTopConcept: inverse property ofskos:topConceptOfskos:broaderis used to link items under the 2nd level to their parent
Proposed mappings
Used namespaces
Entities
| Components | RDF classes | Comments |
|---|---|---|
| Registry | dcat:Catalog | |
| Register | dcat:Dataset | |
| Item | prv:DataItem | |
dcat:Dataset | Only when the item has child items |
| Item classes | RDF classes | Other RDF classes |
|---|---|---|
| Theme | skos:Concept | |
| Application schema | skos:Concept | owl:Ontology? |
| Code list / Metadata code list | skos:ConceptScheme | |
| Code list value | skos:Concept | |
| Feature concept | skos:Concept | rdfs:Class? |
| Glossary item | skos:Concept | others? |
| Document | foaf:Document | dct:Standard? |
Standard / common attributes
| Attributes | Registry, Register | Item | All items modelled as skos:Concept's | Status |
|---|---|---|---|---|
| Base URI + URI name | @rdf:about | stable | ||
| URI name | dct:identifier | stable | ||
| Label | dct:title | +skos:prefLabel | stable | |
| Definition | dct:description | +skos:definition | stable | |
| Description | vann:usageNote | testing | ||
| Language | dct:language | stable | ||
| Status | adms:status | stable | ||
| This version | owl:sameAs | unstable | ||
| Latest version | adms:last | stable | ||
| Manager | dct:publisher | - | unstable | |
| Control body | dct:creator | - | unstable | |
| Owner | dct:rightsHolder | - | stable | |
Content of RDF representation
- What is in the original records concerning the registry, registers and items
- Information on the available distributions - implicit in the original records – in terms of formats (and languages)
The part concerning distributions makes use of:
- For formats:
- For languages:
- URIs available in the corresponding authority table operated by the Metadata Registry of the Publications Office of the EU (OP) [MDR-LANG]
| NOTE | Alternatively to the IANA MIME media types registry, another option is to use the OP's authority table of file types [MDR-FT]. |
|---|
The OP's authority tables are already used in the metadata records of the EU Open Data Portal, and their use is recommended in the DCAT Application Profile for Data Portal in Europe (DCAT-AP).
Example of RDF representation
Registry
The example can be downloaded in the following RDF serialisations:
- RDF/XML (attached: registry.rdf)
- Turtle , JSON-LD (through RDF Translator)
Register (code list register)
The example can be downloaded in the following RDF serialisations:
- RDF/XML (attached: register-code-list.rdf)
- Turtle , JSON-LD (through RDF Translator)
Item (code list)
The example can be downloaded in the following RDF serialisations:
- RDF/XML (attached: item-code-list.rdf)
- Turtle , JSON-LD (through RDF Translator)
Child item (code list value)
The example can be downloaded in the following RDF serialisations:
- RDF/XML (attached: child-item-code-list-value.rdf)
- Turtle , JSON-LD (through RDF Translator)