CRAFTS: Configurable REST APIs for Triple Stores

Abstract

Massive amounts of Linked Open Data are readily available to anyone who wants to use them. Unfortunately, Semantic Web technologies such as SPARQL and RDF remain unfamiliar to the majority of web developers, more used to REST APIs. This paper addresses the challenge of accessing Linked Open Data through REST APIs. Configurable REST APIs For Triple Stores (CRAFTS) is the tool devised for this purpose. CRAFTS allows knowledge engineers to configure REST APIs over multiple triple stores. CRAFTS automatically handles the translation of API calls into SPARQL queries, delivering results in JSON format. Web developers can then use a CRAFTS API to read and write Linked Open Data. The API of CRAFTS is uniform, domain-independent, and described with the OpenAPI specification. A reference implementation of CRAFTS is published in a GitHub repository, and a live test site is readily available since February 2021. CRAFTS is currently employed in eight different applications, with more than 2.4K users, and more than 260K API calls.