A Plug-in Architecture for Self-Adaptive Web Service Compositions

Several approaches have been proposed to introduce self-management capabilities for web service compositions. However, most of these works are limited as they are not extensible, i.e., new self-adaptation features cannot be supported, and even if that is possible then still this cannot be done dynamically while the composite services are running. In addition, many of these works are not based on the service composition standard WS-BPEL. In this paper, we propose a plug-in architecture for self-adaptive web service composition, in which self-adaptation features are well-modularized in aspect based plug-ins. Our approach supports application-specific adaptation scenarios, is easily extensible, and allows self-adaptation logic to be hot-deployed on running process instances. We have implemented this architecture and several plug-ins using the dynamic aspect-oriented workflow language AO4BPEL.