Re: JMeter DSL discussion

[Vladimir Sitnikov]

I've been improving tests, and I realized there's a small change that
brings a decent way to build test plans.

I've updated PR https://github.com/apache/jmeter/pull/678
The PR includes samples for both Kotlin and Java
(see OpenModelThreadGroupConfigElementTest
and OpenModelThreadGroupConfigElementJavaTest).

I think we can merge it and make incremental improvements later.
The good part is that DSL is usable for all the components with no
modifications.

I might miss certain cases, however, it looks nice, at least for testing
JMeter itself.

WDYT?

Here's Java code:

HashTree tree = testTree(b -> {
    b.add(TestPlan.class, tp -> {
        b.add(OpenModelThreadGroup.class, tg -> {
            tg.setName("Thread Group");
            // 5 samples within 100ms
            // Then 2 sec pause to let all the threads to finish,
especially the ones that start at 99ms
            tg.setScheduleString("rate(50 / sec) random_arrivals(100 ms)
pause(2 s)");
            b.add(listener);
            b.add(CounterConfig.class, c -> {
                c.setVarName("counter");
                c.setIncrement(1);
            });
            b.add(DebugSampler.class, dbg -> {
                dbg.setName("${counter}");
                dbg.setDisplayJMeterProperties(false);
                dbg.setDisplayJMeterVariables(false);
                dbg.setDisplaySystemProperties(false);
            });
        });
    });
});

Here's Kotlin code:

val tree = testTree {
    TestPlan::class {
        OpenModelThreadGroup::class {
            name = "Thread Group"
            // 5 samples within 100ms
            // Then 2 sec pause to let all the threads to finish,
especially the ones that start at 99ms
            scheduleString = "rate(50 / sec) random_arrivals(100 ms)
pause(2 s)"
            listener()
            CounterConfig::class {
                varName = "counter"
                increment = 1
            }
            DebugSampler::class {
                name = "\${counter}"
                isDisplayJMeterProperties = false
                isDisplayJMeterVariables = false
                isDisplaySystemProperties = false
            }
        }
    }
}

Vladimir