WSCLim is a tool that automatically executes tests for significantly load testing Web service compositions described in BPEL. It considers the limitations of WS-BPEL Compositions under load conditions. WSCLim is based on Timed Automata as model for specifying requirements to test under various load conditions, a distributed testing architecture, an algorithm for online load test generation and execution, a log analysis technique and finally an algorithm for limitations detection under load.
WSCLim is a developed tool in Java code. It allows studying the limitations of Web service compositions under a given load on two main steps:
- Online testing: it is used to observe the functioning of the BPEL process under test considering a given load condition and to record its different actions. Also, it is used to store performance data.
- Offline analysis: it consists in analyzing the results of online testing in order to generate a final test report in which we present the test verdict of each BPEL instance invocation.
The required inputs for our testing tool, as shown in the figure, are:
- SUT (System Under Test): a Web service composition implemented in BPEL. In our case, this BPEL process is designed with JDeveloper and deployed on Oracle BPEL Application Server.
- Specification (TA): the Timed Automata specifying the SUT. It is designed using UPPAAL.
- Threads number : the number of concurrent calls of the composition under test.
- Delay between each two successive invocations of the BPEL process under test.
As output, WSCLim generates a:
- Test report: contains the identifiers of created instances and its corresponding detailed verdicts.
- Graph showing test statistics: represents the PASS percentage (and FAIL percentage), natures and causes of FAIL verdicts.
- Graph showing test statistics: represents the CPU utilization and the memory utilization.