Web services robustness testing

Abstract

Web services are a new paradigm for building software applications that has many advantages over the previous paradigms; however, Web Services are still not widely used because Service Requesters do not trust services that were built by others. Testing can assuage this problem because it can be used to assess the quality attributes of Web Services. This thesis proposes a framework and presents a proof of concept tool that can be used to test the robustness and other related attributes of a Web Service. The tool can be easily enhanced to assess other quality attributes. The framework is based on analyzing Web Services Description Language (WSDL) documents of Web Services to find what faults could affect the robustness quality attributes. After that using these faults to build test case generation rules to assess the robustness quality attribute of Web Services. This framework will give a better understanding of the faults that may affect the robustness quality attribute of Web Services, how these faults are related to the interface or the contract of a Web Service under test, and what testing techniques can be used to detect such faults. The approach used in this thesis for building test cases for Web Services was used with many examples in order to demonstrate its effectiveness; these examples have shown that the approach and the proof of concept tool are able to assess the robustness of Web Services implementation and Web Services platforms. Four hundred and two test clients were automatically built by the tool, based on the test cases rules, to assess the robustness of these Web Services examples. These test clients detected eleven robustness failures in the Web Services implementations and nine robustness failures in the Web Services platforms. Also the approach was able to help in comparing the robustness of two different Web Services platforms, namely Axis and GLUE. After deploying the same Web Services in both of these platforms; Axis showed less robustness and security failures than GLUE.