In gatling, how do I validate the value of a string extracted via the css check?

Question

I'm writing a Gatling simulation, and I want to verify both that a certain element exists, and that the content of one of its attributes starts with a certain substring. Eg:

val scn: ScenarioBuilder = scenario("BasicSimulation")
  .exec(http("request_1")
  .get("/path/to/resource")
  .check(
    status.is(200),
    css("form#name", "action").ofType[String].startsWith(BASE_URL).saveAs("next_url")))

Now, when I add the startsWith above, the compiler reports an error that says startsWith is not a member of io.gatling.http.check.body.HttpBodyCssCheckBuilder[String] . If I leave the startsWith out, then everything works just fine. I know that the expected form element is there , but I cant confirm that its @action attribute starts with the correct base.

How can I confirm that the attribute start with a certain substring?

Answer 1

Refer this https://gatling.io/docs/2.3/general/scenario/

I have copied the below from there but it is a session function and will work like below :-

doIf(session => session("myKey").as[String].startsWith("admin")) {  // executed if the session value stored in "myKey" starts with "admin"  exec(http("if true").get("..."))}