Passing parameter - number of users - scala

Question

I'm using gatling in linux terminal. When I pass parameter like described in github I get error:
value users is not a member of Integer
This is my code:
package mypackage
import io.gatling.core.Predef._
import io.gatling.http.Predef._
import io.gatling.jdbc.Predef._
import io.gatling.http.Headers.Names._
import scala.concurrent.duration._
import bootstrap._
import assertions._
import util.Random
class MySimulation extends Simulation {
val usersCount = Integer.getInteger("users", 1)
val links = csv("links.csv").random
val httpProtocol = http
.baseURL("http://mywebsite.com:8080/")
.acceptCharsetHeader("ISO-8859-1,utf-8;q=0.7,*;q=0.7")
.acceptHeader("text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8")
.acceptEncodingHeader("gzip, deflate")
.acceptLanguageHeader("fr,fr-fr;q=0.8,en-us;q=0.5,en;q=0.3")
.disableFollowRedirect
val headers_1 = Map(
"Keep-Alive" -> "115")
val headers_3 = Map(
"Keep-Alive" -> "115",
"Content-Type" -> "application/x-www-form-urlencoded")
val scn = scenario("big project benchmark")
.repeat(50) {
feed(links)
.exec(
http("request_1")
.get("${pageUri}")
.headers(headers_1)).pause(1000 millisecond)
}
setUp(scn.inject(ramp(usersCount users) over (30 seconds)))
.protocols(httpProtocol)
.assertions(global.successfulRequests.percent.is(100), details("request_1").responseTime.max.lessThan(1000))
I start this in terminal using:
JAVA_OPTS="-Dusers=300" ./gatling.sh -s mypackage.mySimulation -on testing -sd test1
Please, be patient, because I'm totally new to scala and gatling. Thanks for any help.

Answer 1

The problem comes from the usersCount users part of the setUp.
In Scala, this is interpreted as usersCount.users which, in our case does not exist since Integer does not have a users method.
I think (but I'm not sure since I cannot test it right now), that you should make usersCount an Int like so: val usersCount: Int = Integer.getInteger("users", 1).toInt.
Hope this helps!
PS: The reason you should convert Integer to Int is because of implicit conversions. This is a really powerful feature of Scala.
PPS: The wiki documentation was valid for Gatling 1.X, it will be updated accordingly for Gatling 2.X