As many organizations embrace DevOps on IBM Z today, one of the key challenges is undoubtedly Shift Left testing, which helps the developers sustaining their velocity by providing them with the capability to test the applications they develop as soon as possible. This capability applies to Unit testing but also to Integration testing, a discipline aimed towards the validation of a set of programs that represent a consistent business domain. IBM provides the IBM Z Virtual Test Platform (VTP) tool to help z/OS Developers and Testers to Shift-Left some Application Integration Test.
VTP became generally available in late 2020, and new capabilities were released in June 2021 to improved setup and usability. However, getting started with tools and using the variety of features can be daunting, so a new series of technical videos has been created to help those working with VTP to see how it works firsthand. The following videos for VTP are available in the IBM Media Center:
- Get help setting up IBM Z VTP
To help z/OS systems programmers with the installation of IBM Z DevOps solutions, the Host Configuration Assistant (HCA) is the ideal companion of z/OS admins who are looking at a guided, condensed documentation that is listing everything that needs to be done to configuration all the necessary components. A video was created to demonstrate how it can be used to save time in the setup phase: https://mediacenter.ibm.com/media/1_eabfqrn9
Additionally, a video was created to highlight the major steps of configuring IBM Virtual Test Platform on z/OS. This video covers the z/OS traditional configuration to activate, enabling the use of VTP’s main features: https://mediacenter.ibm.com/media/1_1n588yfh
- Create and Update VTP tests for a CICS application
VTP is able to record CICS transactions and programs running in a CICS context. The generated file, called a playback file, can then be used to replay the recorded transaction without needing a CICS environment setup and configured. This replay capability is particularly helpful for integration tests, that don’t necessarily contain all the required ecosystem (CICS regions, DB2 subsystems, …). The VTP’s replay feature stubs out all the calls to external systems, focusing on passing the data in the program calls flow. A video has been created to demonstrate how to record a CICS transaction and replay it with VTP in a stubbed CICS environment: https://mediacenter.ibm.com/media/1_j0msnpbu
As developers are implementing new features in their applications, there may be cases where the program requires an update, so the flow logic changes. To a certain extent, VTP is designed to support those changes when replaying the program call chain. During an integration test where the call chain changed, VTP is able to detect that the replayed data doesn’t match the recorded data and can generate a second playback file that contains the new replayed data. This handy feature simplifies the developer’s workflow as it avoids recording again the same transaction. This feature is highlighted in this video: https://mediacenter.ibm.com/media/1_zupnbu2c
This series of video was designed to kickstart developers’ adoption of VTP, but many more features are near at hand to implement early Integration tests in the development practices on z/OS.