Core: custom metrics and assertions

[domi-nika60]

Hi,

I'm unable to make assertion in exec block of code (Scala test) that fails the test if it's not passed.
My Gatling version I'm using is '3.7.3'

I'm doing request to http separately like:

 val request = exec {
    http("GET SOMETHING")
      .get(<some endpoint>)
      .header(<some header>)
      .check(status.exists, status.saveAs("get.statusCode"))
}

And then I'm using it in definition of function like:

def someFunction = {
     exec(
        request.during(<some time>) {
           exec(
             session => {
              allRequests += 1
              if (session("get.statusCode").as[Int] == 200) {
                successes += 1
              }
              session
            }
          )
})

I'd like to add some assertion in this someFunction to check, if percentage of successful requests (statusCode == 200) is not less than 10.

I've tried adding something like:

        assert((successes*100)/allRequests >= 10))

But it does not fail the test scenario, when it's below that 10%.
I've tried using exitHereIfFailed or any of those types from Gatling documentation (but with no luck).

Moreover, I also added .assertions(forAll.failedRequests.count.is(0)) in setUp section. This also did not work (test is still ending with Build Successful).

I'm aware, there is also possibility to use an assertion for global requests (assertions(global.successfulRequests.percent.gt(10))), but I need my custom one.

Also I do not want to use any check, because counters (allRequests and successes) must be in request.during(<some time>) block.

Is there any option to use my custom counters and check percentage of successful request as in my example?

[slandelle]

We want assertions to be:

• serializable over the wire (hence use an AST, not arbitrary functions)
• computed against Gatling metrics (not arbitrary ones you would compute manually)

In short, you would like Gatling to have custom metrics (counters, but others might want durations, often called timers) and that they support assertions.

That's something we're considering, but it will probably only make its way in Gatling Enterprise.

[domi-nika60]

Okey, I see. Thanks for so fast response.
In this situation, is there any other way to check if e.g. at least 10% requests return proper value?

[slandelle]

Can't you explicitly check for status 200, instead of using the default one?

[domi-nika60]

I was thinking about it. But the counters are not working properly in this http request exec. So that, I assumed that I need to use them in request.during(<some time>) block. Am I doing sth wrong?