Automated choreography repair

Abstract

Choreography analysis is a crucial problem in concurrent and distributed system development. A choreography specifies the desired ordering of message exchanges among the components of a system. The realizability of a choreography amounts to determining the existence of components whose communication behavior conforms to the given choreography. The realizability problem has been shown to be decidable. In this paper, we investigate the repairability of un-realizable choreographies, where the goal is to identify a set of changes to a given un-realizable choreography that will make it realizable. We present a technique for automatically repairing un-realizable choreographies and provide formal guarantees of correctness and termination. We demonstrate the viability of our technique by applying it to several representative unrealizable choreographies from Singularity OS channel contracts and Web services.