GR4PHP: A Programming API for Consuming E-Commerce Data from the Semantic Web

Nowadays, large data collections are made available on-line for free. The liberalized data is predominantly accessed via Web services. The interaction with such Web services is facilitated by RESTful Web APIs and programming libraries that provide a convenient means for Web developers to build intelligent applications and mash-ups. However, for typical Web developers it is still hard to include the growing amount of e-commerce data on the Semantic Web in applications. Fetching useful data from public SPARQL endpoints requires substantial expertise, such as regarding the popularity of competing RDF modeling patterns, data cleansing heuristics, etc. In this paper, we propose an architecture and implementation of a PHP library for consuming e-commerce data in RDF expressed in terms of the GoodRelations vocabulary. Our approach (1) provides an efficient way of fetching information about stores, offers, product models, and opening hours from a SPARQL endpoint, and (2) hides the complexity of SPARQL and GoodRelations modeling patterns. We show that our approach significantly reduces the amount of time for a respective implementation. Furthermore, our approach has been applied successfully in a real-world application.