Automated testing of MES systems is becoming increasingly more popular these days, and for a good reason. When done right, it can save your company a lot of time and expense on testing while providing reliable information on the state of your MES. Like in manual testing, automated tests can also be divided into functional (i.e., ‘does it work as designed?’) and non-functional (i.e., check software speed, stability, integration, etc.). The overwhelming majority of automated MES testing are usually functional tests, using well-established tools like Selenium Web Driver to check business operations. But this is only the tip of the iceberg – automated testing software can do a lot more these days.
Depending on your industry and legal regulations, preparing master data or specific test data can be tedious and time-consuming to a downright pain in the neck. It may require copying data from production to test/QA environment or creating the data manually in the QA environment, and then copying or altering it for each iteration of testing. Sometimes, setting up test data takes longer than actually performing the test case. That is where automated testing tools can take over and shine. Once provided with specific parameters, they can quickly and painlessly generate any amount of test data that is always correct. When the testing is complete, the data can be erased to save disk space.
Given MES systems’ nature, the data they use often comes from ERP software and is passed down to your industrial automation systems, like SCADA or PLCs. While it is common to have a test instance of the ERP system set up in the test environment, it is not necessary – a Process Order or Work Order with parameters to start an operation can be easily emulated with webservice tools. Simulating the behavior and responses of automation systems is far trickier (as there is no dedicated software for that) but doable with the right tools and expertise. Reading and interpreting the output of the PLCs saved in the database, also something automated testing software can do, is relatively simple in comparison. With these start and endpoints, the entire business flow can be run from start to finish, and test results can be recorded in minutes. Because test automation tools can also be configured to generate test reports, you can have them laid out in a user-friendly, readable MS Word or PDF file.
For test automation to make economic sense, it is vital to define the scope of automated testing carefully. The best candidates for automation are the cases that are both critical for your business operation and that do not frequently change, to keep maintenance down to a minimum. Your testers will need to look into the size and complexity of your solution and your business, discuss your needs, and decide on the optimal testing approach and tools. No matter what industry your company works in, or how complicated your business processes are, there is an automated testing tool out there that can be used (or adapted) to test them.
We will not lie to you: creating a well-designed and sustainable automated testing process takes quite a bit of effort and expenditure at first. Getting to know your solution and business and moving from the assessment to the pilot phase (where one or two sample automated test cases are developed to show the potential return on investment), to implementation can take several weeks. Obtaining licenses for any non-free software (or customizing open-source tools) and a good version control system (for documenting all releases, builds, and changes in your solution and the corresponding automated testing suite(s)) may require some budgeting. The investment will pay off as soon as you need to make updates to your automated test suite, e.g., after an upgrade of your MES solution. With a well-designed automated test suite, it will only take changing a dozen or so lines of code or adding a single module instead of tedious revisions and multiple rewrites across the entire suite. Given that maintenance is a semi-regular occurrence in the software lifecycle, the savings will build up over time, lightening the strain on your budget long after the first automated test case is used.
We hope we have shown here that despite the initial hurdles, test automation is a worthwhile investment. At Andea, we have had years of experience automating MES tests in a range of industries – we know how to find the right software for the job and push it to its limits (or sometimes beyond!).
Łukasz Howorski is a Project Excellence Department Manager and a QA Architect with rich and diverse experience in test management, execution, and test automation. ISTQB and AGILE certificates help him create full test strategies that are tailored to client requirements. His technical and organizational skills allow him to implement frameworks not only in the test automation field but also in improving test processes using different approaches. He likes sharing his findings with the team, improving their skills one nugget of knowledge at a time.