Choreographies: using Constraints to Satisfy Service Requests

Interacting with a web service enabled marketplace to achieve a complex task involves sequencing a set of individual service operations, gathering information from the services, and making choices. In the context of coreographies of web services, we propose to encode the problem of issuing requests as a constraint problem. In particular, we provide a choreographic framework to handle requests, we show how request encoding is performed, and we illustrate an implementation using the Choco constraint system.