OpenAPI framework for the Web of Things

The Web of Things (WoT) Architecture recommendation of W3C defines a framework for integrating Things (e.g. devices) into the Web. It establishes an information representation of Things based on JSON-LD and RESTful API interfaces to enable access to Things. Leveraging the latest results on hypermedia construction and documentation of RESTful APIs, we argue that OpenAPI can also be used to provide documentation of Things that adheres to the W3C Architecture recommendation. OpenAPI is a widely accepted industry standard endorsed by prominent industry vendors and user communities. Therefore, it is mature and can become acceptable. An essential part of the approach is a mechanism that facilitates the generation of OpenAPI Thing Descriptions and a Web proxy that implements access to Things on the Web. An implementation of the API is also proposed and evaluated. Last but not least, OpenAPI achieves uniformity of representation of both types of WoT entities (i.e. Web services and Things) that co-exist and interact with each other in an application. This has a positive impact on the way WoT applications are designed and implemented.