AppTesterTM is a useful supporting tool for test automation and validation in automated modernization projects. The roles of AppTester are
- to record test cases on legacy systems (3270, Unix terminal, Windows GUI, batch, etc.),
- maintain test definitions,
- replay them on migrated applications in the target scenario,
- evaluate the results automatically and provide overall statistics of success and coverage rate.
Regression testing and QA is critical for all iterative modernization projects, so this tool significantly reduces risk and required effort.
The assumption of legacy application migration is that the migrated application does exactly what the legacy system did: produces the same output for a certain input.
This is true for batch processing when a captured database state as a baseline is modified by the application. The same – but migrated – database in the new world is modified exactly the same way by the converted application. Batch applications – by the thousands – must be repeatedly run and tested to prove identity.
This is also true for applications with a user interface: the output, be it a screen visible to the user or database changes, must be identical in both systems. For hundreds of screens with many different variations of user input must be tested repeatedly. These test cases are usually defined by the customer and recorded in the legacy system. Then replayed in the converted system and the outputs are compared accordingly.
The recording, management, playback, and comparison is managed by the AppTester that comes with a management interface.