Photorealistic Semantic Web Service Groundings: Unifying RESTful and XML-RPC Groundings Using Rules, with an Application to Flickr

Semantic Web services achieve effects in the world through Web services, so the mechanism connecting the ontological representations of services with the on-the-wire messages—the grounding—is of paramount importance. The conventional approach to grounding is to use XML-based translations between ontologies and the SOAP message formats of the services, but these mappings cannot address the growing number of non-SOAP services, and step outside the ontological world to describe the mapping. We present an approach which draws the service’s interface into the ontology: we define ontology objects which represent the whole HTTP message, and use backward-chaining rules to translate between semantic service invocation instances and the HTTP messages passed to and from the service. We show how this approach can be used to access the Flickr photo-sharing service through both its RESTful and XML-RPC interfaces.