This work presents how to translate OWL to OAS.

1. Paola Espinoza-Arias1, Daniel Garijo2, Oscar Corcho1
1Ontology Engineering Group
Universidad Politécnica de Madrid
2Information Sciences Institute
University of Southern California
pespinoza@fi.upm.es
@mijaspao
4 November 2020
Virtual - CMOMM4FAIR
Mapping the Web Ontology
Language to the
OpenAPI Specification
This work has been supported by a Predoctoral grant from the I+D+i program of the Universidad Politécnica
de Madrid and the Spanish project DATOS 4.0: RETOS Y SOLUCIONES (TIN2016-78011-C4-4-R).
Workshop on Conceptual Modeling, Ontologies and (Meta)data
Management for FAIR Data co-located with the 39th
International Conference on Conceptual Modeling

2. “Mapping the Web Ontology Language to the OpenAPI Specification” by Paola Espinoza-Arias, Daniel Garijo and Oscar Corcho
Introduction
2
LOD cloud: https://lod-cloud.net/#diagram
Adoption of Knowledge Graphs (late 2019): https://www.slideshare.net/Frank.van.Harmelen/adoption-of-knowledge-graphs-late-2019
I need to use
the KG’s data
OWL
SPARQL EndpointOntologies Web developer

3. “Mapping the Web Ontology Language to the OpenAPI Specification” by Paola Espinoza-Arias, Daniel Garijo and Oscar Corcho
Introduction
3
§ OpenAPI Specification (OAS):
o Is a de facto standard
o Represented in either YAML or JSON.
o Many tools for editing, documenting, etc.
OAS
Last OAS version : http://spec.openapis.org/oas/v3.0.3
List of available tools for OAS: https://openapi.tools

4. “Mapping the Web Ontology Language to the OpenAPI Specification” by Paola Espinoza-Arias, Daniel Garijo and Oscar Corcho
Outline
4
§ Related Work
§ Mapping OWL to OAS
o Method
o Coverage
o Implementation
§ Conclusions and Future Work

5. “Mapping the Web Ontology Language to the OpenAPI Specification” by Paola Espinoza-Arias, Daniel Garijo and Oscar Corcho
Proposal OWL to OAS
mapping available
Expressiveness REST Server
OBA extended ✓ ++ ✓
Proposal OWL to OAS
mapping available
Expressiveness REST Server
OWL2OAS x + x
OBA ✓ - ✓
Related Work
§ Specifications: Linked Data API, Linked Data
Platform, or Triple Pattern Fragments.
§ Proposals to generate APIs on top of SPARQL
endpoints:
a) From SPARQL queries:
• BASIL (Daga E. et al, 2015) and GRLC (Meroño A. et
al, 2016)
b) From ontologies:
• OWL2OAS (Hammar K., 2020) and OBA (Garijo D. and
Osorio M., 2020)
5
(✓= included, x = not included, - = less coverage, and + = more coverage of OWL constructs)

6. “Mapping the Web Ontology Language to the OpenAPI Specification” by Paola Espinoza-Arias, Daniel Garijo and Oscar Corcho
Related Work
§ Ontology-Based APIs (OBA)
o Framework to create REST APIs from OWL ontologies
o https://oba.readthedocs.io
6
Garijo, D. and Maximiliano Osorio. “OBA: An Ontology-Based Framework for Creating REST APIs for Knowledge Graphs.” (2020) https://arxiv.org/abs/2007.09206

7. “Mapping the Web Ontology Language to the OpenAPI Specification” by Paola Espinoza-Arias, Daniel Garijo and Oscar Corcho
Method for Mapping OWL to OAS
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http://w3id.org/OWLToOAS
OWL
OAS
• Implementation details
• Examples
• Coverage (OWLtoOAS
profile)
• Ontology metadata
• Path and Schema naming
strategy

8. “Mapping the Web Ontology Language to the OpenAPI Specification” by Paola Espinoza-Arias, Daniel Garijo and Oscar Corcho
Mapping coverage
8
§ Our mapping specification covers:
§ Limitations:
o Some OWL constructs don’t correspond to OAS definitions
e.g. Person is equivalent to a Human: Person owl:EquivalentClass
Human
o The OAS doesn’t support complex boolean restrictions. e.g.
ChildlessPerson is a Person who is not a Parent: ChildlessPerson
rdfs:subClassOf (Person owl:intersectionOf (owl:complementOf Parent))
https://owl-to-oas.readthedocs.io/en/latest/mapping/#owltooas-profile
Expressivity Coverage Expressivity Coverage
Functional (F) ✓ Nominal values (O) ✓
Existential (E) - Inverse properties (I) x
Unions (U) - Cardinality (N) ✓
Concept Negation (C) ✓ Qualified Cardinality (Q) ✓
Hierarchies (H) ✓ Data types (D) ✓
Role disjointness (R) x
(✓= covered, - = partially covered, and x = not covered)

9. “Mapping the Web Ontology Language to the OpenAPI Specification” by Paola Espinoza-Arias, Daniel Garijo and Oscar Corcho
Mapping implementation
9
Mapping OWL to OAS implementation: https://github.com/KnowledgeCaptureAndDiscovery/OBA/releases/tag/3.4.0
OWL
OAS
(ttl)
(YAML)

10. “Mapping the Web Ontology Language to the OpenAPI Specification” by Paola Espinoza-Arias, Daniel Garijo and Oscar Corcho
Conclusions and future work
10
§ Conclusions:
o A mapping specification between the OWL and OAS.
o A mapping implementation as an extension of OBA.
o Adherence to the FAIR principles.
o Some OWL constructs are not covered by the mapping.
§ Future work:
o Generate the names for API resource paths and schemas
from the ontology annotations.
o Annotate APIs with key metadata.
o Combine our API definitions with the Shapes Constraint
Language (SHACL).

11. Paola Espinoza-Arias1, Daniel Garijo2, Oscar Corcho1
1Ontology Engineering Group
Universidad Politécnica de Madrid
2Information Sciences Institute
University of Southern California
pespinoza@fi.upm.es
@mijaspao
4 November 2020
Virtual - CMOMM4FAIR
Mapping the Web Ontology
Language to the
OpenAPI Specification
This work has been supported by a Predoctoral grant from the I+D+i program of the Universidad Politécnica
de Madrid and the Spanish project DATOS 4.0: RETOS Y SOLUCIONES (TIN2016-78011-C4-4-R).
Workshop on Conceptual Modeling, Ontologies and (Meta)data
Management for FAIR Data co-located with the 39th
International Conference on Conceptual Modeling