Test Case Generation of Web Service Composition based on CP-nets

Web service composition is an error prone task. Based on CP-nets (colored petri net) models, an approach of test case generation is proposed for web service compositions coded in BPEL. In this approach the semantic of BPEL concurrence and some special features are well dealt. Firstly, BPEL processes of a web service composition is translated into CP-nets models, then depth-first traversal works on the models immediately, and results in some sequence test paths. Secondly, after these sequence test paths merged into program executable units (PEU for short), the constraint set of these units is solved and filtered and formed into test cases. Finally, an application of the approach is illustrated with an example, which more efficiency shown with 7 test units less than 9 test paths appeared in a reference for same example, 3 test cases far less than formal works.