An XML-based approach to automated software testing

Abstract

The advantages of automating the functional testing of application software are well-known, but the manner of automation can lead to difficulties in authenticating the test coverage. In this paper we consider the class of automated tests in which a driver tool simulates the input and responses of a human operator and sequentially checks the output generated by the application software. The driver tool commonly employs its own language to describe the tasks it can be required to perform, for example:• Issue a sequence of characters that simulate input from the keyboard.• Verify that a segment of the display buffer contains the expected bit pattern.Although these tasks are simply stated, the language to effect them in a test script can become complex and hard to maintain. Furthermore, reading the driver tool program is not an effective way to confirm that the test script performs its tasks to the test specification.XML (eXtensible Markup Language)[1)] scripts offer a rigorous intermediate description that can be readily translated into both the driver tool test script and a readable statement of the task the test performs. The advantages accruing from the use of XML are:• The XML scripts are easy to edit, simplifying basic script maintenance. New steps can be included for testing bug fixes.• Content review becomes much easier, as the relevant aspects of the script can be rendered in a readily readable form, such as HTML;• Global changes become feasible, as the structured nature of XML documents makes it possible to search for specific element content;• The structure of the XML document can itself be checked, for example using a validating editor such as Xeena [2)].In the next section we describe an example of automated testing using a driver tool, based on XML scripts. The application being tested is called Wired for Learning [3)] and provides the IT infrastructure for schools to:• Enhance communication between teachers, students and parents.• Enable teachers to plan and share ideas for lessons and activities, linking in with national standards.• Organize team projects involving teachers and students across classes and schools, with the option of inviting members of the community to provide additional information.• Provide an events calendar to keep everyone up to date with what is happening in the school.• Allow teachers easily to create their own home pages for information dissemination.