Towards Offline Support for RESTful Systems

Abstract

Representational State Transfer (REST) is an efficient and by now established architectural style for distributed hypermedia systems. However, REST has not been designed for offline operations, yet many applications must also keep functioning when going offline for more than a few seconds. Burdening the programmer with knowledge about offline status is undesirable. RESTful applications can be described by a formal model. Therefore, we define a function to derive a formal model of the proxy for handling offline support on the client-side. We then extend existing caching approaches so that a client-side proxy can transparently hide the offline status from the application. We validate our solution with a proxy layer that covers all test cases derived from the model. Using our model and proxy, clients do not have to know and worry about whether they are online or offline.