Reusable and Extensible Fault Tolerance for RESTful Applications

Abstract

Despite the simplicity and scalability benefits of REST, rendering RESTful web applications fault-tolerant requires that the programmer write vast amounts of non-trivial, ad-hoc code. Network volatility, HTTP server errors, service outages- -- all require custom fault handling code, whose effective implementation requires considerable programming expertise and effort. To provide a systematic and principled approach to handling faults in RESTful applications, we present FT-REST- -- an architectural framework for specifying fault tolerance functionality declaratively and then translating these specifications into platform-specific code. FT-REST encapsulates fault tolerance strategies in XML-based specifications and compiles them to modules that reify the requisite fault tolerance. To validate our approach, we have applied FT-REST to enhance several realistic RESTful applications to withstand the faults described in their FT-REST specifications. As REST is said to apply verbs (HTTP commands) to nouns (URIs), FT-REST enhances this conceptual model with adverbs that render REST reliable via reusable and extensible fault tolerance.