Flexible Pattern Monitoring for WS-BPEL through Stateful Aspect Extension

The execution of composite web services with WS-BPEL relies on externally autonomous Web services. This implies the need to constantly monitor the running behavior of the involved parties. Moreover, monitoring the execution of such processes is critical to enforce business policies and meet reliability goals. This paper proposes a stateful aspect extension to WS-BPEL, as a solution to support flexible behavior pattern monitoring for composite Web services. Specifically, in the stateful aspect, history-based pointcut specifies the pattern of interest within a range, while advice describes the associated action to manage the process if the specified pattern occurs. We also present its implementation based on finite state automata through runtime weaving mechanism. Our experiments indicate the proposed monitoring approach incurs minimal overhead.