gatling cant keep users lopping the scenario for a period of time

Gatling (Open-Source)
1

I want basically to add some load to some apis mocking user flow. Something like ramp up to 20 users that do the same thing all the time for a period of time and then ramp down

  private val httpProtocol = http
    .baseUrl(baseUrl)
    .doNotTrackHeader("1")
    .header("Content-Type", "application/json")
    .acceptEncodingHeader("gzip, deflate")
    .userAgentHeader("Gatling load test")
    .disableFollowRedirect

  private val scn = scenario("User login")
    .exec(http("login successful")
    .post("/customer-service/api/login")
    .body(StringBody("""{ "username": "test@mail.com", "password": "12345" }"""))
    .check(status.is(200)))

  setUp(scn.inject(rampUsers(20) during (20 minutes))).maxDuration(10 minutes)

At the moment I can see how the users are ramping up but terminating after they do one request. In the active user graph I can see a peaky mountain rather than the expected rampup slope then a steady line and then a ramp down line to 0

Thanks!

2

I want basically to add some load to some apis mocking user flow. Something like ramp up to 20 users that do the same thing all the time for a period of time and then ramp down

  private val httpProtocol = http
    .baseUrl(baseUrl)
    .doNotTrackHeader("1")
    .header("Content-Type", "application/json")
    .acceptEncodingHeader("gzip, deflate")
    .userAgentHeader("Gatling load test")
    .disableFollowRedirect

  private val scn = scenario("User login")
    .exec(http("login successful")
    .post("/customer-service/api/login")
    .body(StringBody("""{ "username": "[test@mail.com](mailto:test@mail.com)", "password": "12345" }"""))
    .check([status.is](http://status.is)(200)))

  setUp(scn.inject(rampUsers(20) during (20 minutes))).maxDuration(10 minutes)

At the moment I can see how the users are ramping up but terminating after they do one request. In the active user graph I can see a peaky mountain rather than the expected rampup slope then a steady line and then a ramp down line to 0

UP

Thanks!

UPDATE: I found what was missing:

  private val httpProtocol = http
    .baseUrl(baseUrl)
    .doNotTrackHeader("1")
    .header("Content-Type", "application/json")
    .acceptEncodingHeader("gzip, deflate")
    .userAgentHeader("Gatling load test")
    .disableFollowRedirect

  private val scn = scenario("User login")
    .during(3 minutes) {
        exec(http("login successful")
        .post("/customer-service/api/login")
        .body(StringBody("""{ "username": "test@mail.com", "password": "12345" }"""))
        .check(status.is(200)))
  }

  setUp(
    scn.inject(rampUsers(20) during (1 minutes)),
  ).protocols(httpProtocol)

Wrapping it with a during makes it repeat the flow again and again for a period of time. So in my code it takes 1 minute to ram up users then 3 minutes steady load and another 1 minute to rampdown