REST Service Discovery Based on Ontology Model

Abstract

RESTful web services are the new drift that is used for most of the present technical solutions when creating stateless web services. At present world moves towards RESTful web services, the number of available web services is rapidly increasing thereby service discovery can be a challenging task. The present service discovery approaches have deficiencies in semantics, lack of inefficiency, and lower precision rates. The web service usage can be categorized as ‘Provider Developers’ and ‘Consumer Developers’. Provider Developers develop APIs and publish along with Open API specification. Published web services are consumed by Consumer Developers. Consumer Developers integrate thirdparty web services in their solutions yet face difficulties in finding the best suitable service for their needs. Most traditional service discovery approaches depend on semantic specifications like OWL-S. OWL-S is the universal ontology specification to represent RESTful service semantics. This specification was initially created for WSDL and up to the present, there are only a few conversions available for RESTful service to OWL-S. To convert a REST service to a semantic specification, the syntactic of the RESTful service needs to be available. The objective of this Research Study is to propose a solution to reducing the present gap between syntactic and semantics of RESTful service. At present most RESTful service developers incorporate Open API specification formerly known as Swagger to provide syntactically. The main use of the Open API Specification document provides guided documentation for consumers on how to invoke web service. In this document, synthetics are hidden, which can be extremely useful for service discovery, but mostly not used at present. The proposed study aims towards the use of Open API specification to extract syntactic and map syntactic to OWL-S semantic specification. The approach further proposes to provide a keyword-based search engine that can be used to search web services based on IOPE conditions by leveraging the generated semantic specification. As proof of concept for this proposed approach, Lufthansa Swagger API was used to generate semantic specification and service grounding. The search engine was developed to query by keyword and Input/ Output condition based.