Katalon Studio provides a built-in keyword WebUI.takeScreenshot. This feature brings an itchy problem to me. Let me describe the problem and what I have done.
I have developed a Katalon project https://github.com/kazurayam/ContextTrace/tree/master/app. Let’s go through this sample project, which will propose a untility class com.kazurayam.ks.ContextTrace.
As the document tells, the WebUI.takeScreenshot keyword takes an argument fileName, which is optional. What value will the fileName take as default? So let me check it hands-on. I created a testcase script
Also I made a test suite
The test suite calls the aforementioned testcase. When I ran the test suite, I got the result in the Reports folder.
$ tree Reports/20251004_204203
Reports/20251004_204203
└── TS
└── 20251004_204203
├── 1759578150377.png
├── 1759578157116.png
├── 1759578166156.png
├── 1759578172001.png
├── 20251004_204203.csv
├── 20251004_204203.html
├── console0.log
├── execution.properties
├── execution.uuid
├── execution0.log
├── JUnit_Report.xml
├── testCaseBinding
└── tsc_id.txt
3 directories, 13 files
As you see, the WebUI.takeScreenshot() generated a PNG file named with 13 digits appended with postfix .png, like 1759578150377.png.
What is
1759578150377? — It is the value ofnew java.util.Date().getTime(); the Current Epoch Unix Timestamp.
This file name tells me nothing what the PNG image presents. Therefore I can not re-use the PNG files named in this format. These PNG files are just useless for me.
How can I give screenshot files better names? — It’s easy. As the doc WebUI.takeScreenshot tells, I can specify fileName as the 1st argument.
It is a good idea to name the screenshot files with the TestCaseId. I can do it easily. See the test cases source code:
...
WebUI.openBrowser(GlobalVariable.G_SiteURL)
WebUI.takeScreenshot('1-Main_Test_Cases-TC_Verify_Successful_Appointment_-_awkward.png')
...
When I ran the app/Test Suites/TS - awkward, I got the following output in the Console:
$ tree Reports/20251004_212933
Reports/20251004_212933
└── TS - awkward
└── 20251004_212933
├── 1-Main_Test_Cases-TC_Verify_Successful_Appointment_-_awkward.png
├── 2-Main_Test_Cases-TC_Verify_Successful_Appointment_-_improved,Common_Test_Cases-Login_-_awkward.png
├── 20251004_212933.csv
├── 20251004_212933.html
├── 3-Main_Test_Cases-TC_Verify_Successful_Appointment_-_awkward.png
├── 4-Main_Test_Cases-TC_Verify_Successful_Appointment_-_awkward.png
├── console0.log
├── execution.properties
├── execution.uuid
├── execution0.log
├── JUnit_Report.xml
├── testCaseBinding
└── tsc_id.txt
3 directories, 13 files
The PNG files are named better than the original code — the sequence number 1,2,3,4 followed by Test Case ID. Even in the case where 2 or more Test Cases are chained by WebUI.callTestCase() keyword, the file name contains the full information of the chained test cases.
But I hate the test case source code. It is a terrible idea to hard-code a string like "2-Main_Test_Cases-TC2_Verify_Successful_Appointment_-improved,Common_Test_Cases-Login-_awkward.png" in the script. Anyone can imagin, such string literals will make the maintenance job a nightmare.
The com.kazurayam.ks.ContextTrace class can improve my code. See the README how to introduce it. See the test cases source code:
....
WebUI.openBrowser(GlobalVariable.G_SiteURL)
WebUI.takeScreenshot('1-' + ContextTrace.escapedTestCaseIdChain() + '.png')
....
As you see, the test case source code now contains no lenthy string literal, which is replaced with a call to ContextTrace.escapedTestCaseIdChain(). This style makes the code much more maintainable.
When I ran the app/Test Suites/TS - improved, I got the following output in the Console:
$ tree Reports/20251004_213229
Reports/20251004_213229
└── TS - improved
└── 20251004_213229
├── 1-Main_Test_Cases-TC2_Verify_Successful_Appointment_-_improved.png
├── 2-Main_Test_Cases-TC2_Verify_Successful_Appointment_-_improved,Common_Test_Cases-Login_-_improved.png
├── 20251004_213229.csv
├── 20251004_213229.html
├── 3-Main_Test_Cases-TC2_Verify_Successful_Appointment_-_improved.png
├── 4-Main_Test_Cases-TC2_Verify_Successful_Appointment_-_improved.png
├── console0.log
├── execution.properties
├── execution.uuid
├── execution0.log
├── JUnit_Report.xml
├── testCaseBinding
└── tsc_id.txt
3 directories, 13 files
This output is just similar to the “awkward solution”.
The “improved solution” generates 4 screenshot files. This means, the test case scripts repeats the following code 4 times:
WebUI.takeScreenshot('1-' + ContextTrace.escapedTestCaseIdChain() + '.png')
I want to make the code even simpler. I want to have a custom keyword that encapsulates the statements of calling WebUI.takeScreenshot and ContextTrace.escapedTestCaseIdChain(). So I made one more code set.
....
WebUI.openBrowser(GlobalVariable.G_SiteURL)
CustomKeywords.'my.Screenshooter.takeScreenshot'()
....
The my.Screenshooter class is a short Groovy class, as follows:
When I ran the app/Test Suites/TS - modularized, I got the following output in the Console:
$ tree Reports/20251004_213431
Reports/20251004_213431
└── TS - modularized
└── 20251004_213431
├── 20251004_213431.csv
├── 20251004_213431.html
├── console0.log
├── execution.properties
├── execution.uuid
├── execution0.log
├── JUnit_Report.xml
├── snapshots
│ ├── 1-Main_Test_Cases-TC2_Verify_Successful_Appointment_-_modularized.png
│ ├── 2-Main_Test_Cases-TC2_Verify_Successful_Appointment_-_modularized,Common_Test_Cases-Login_-_modularized.png
│ ├── 3-Main_Test_Cases-TC2_Verify_Successful_Appointment_-_modularized.png
│ └── 4-Main_Test_Cases-TC2_Verify_Successful_Appointment_-_modularized.png
├── testCaseBinding
└── tsc_id.txt
4 directories, 13 files
This is the final result. I like it.
The com.kazurayam.ks.ContextTrace class enables Katalon Test Case scripts to get its own TestCaseId programatically. You can use value returned by ContextTrace.escapedTestCaseIdChain() as screenshot file name. You would be able to find more usecases of it.