I want to save the request and response on test suite level

Hi,

Before looking at writing requests and responses, are you sure your script is correctly iterating over the test steps and 'picking' up the step name?

Try using log.info to check.  E.g. in your loop....

testSuite.testCases.each { testCaseName, testCase ->

    log.info("TestCaseName " + testCaseName);

    // path for this testCase
    def folderPathSuite = folderPath + testCaseName + File.separator;
    new File(folderPathSuite).mkdir();
    // for each testStep
    testCase.testSteps.each { testStepName, testStep ->

        log.info("TestStepName " + testStepName);
        def response = testStep.getProperty('Response').getValue();

        log.info(response);

        if(response){
            // define a file
           def file = new File(folderPathSuite + testStepName + '_response.json')
           // get the response and write to file
           file.write(response)
        }