Ad-hoc performance testing a web service with Ammonite and Gatling (Scala)

sample-load-test.sc

/**
 * Load Test an example web service using Gatling
 * 
 * Based on https://gist.github.com/dacr/88c797b05ee968be145eccc77e498888 
 * 
 * ## Prerequisites: 
 *  1. Ammonite installed (http://ammonite.io/)
 *  2. users-query.csv file in same folder as the script. Its' structure is: 
 *    user, query, 
 *    Bob, beavers,
 *    Alice, airbrush,
 *  3. Asset classifier webservice running on localhost:9900 (otherwise modify the baseUrl param below)
 *
 * ## Running: 
 *  1. Execute `amm ./sample-load-test.sc`
 *  2. Open the /tmp/SamplePerformanceTest-20190801114719686/index.html to review the report (of course the timestamp will differ)
 */

import $ivy.`io.gatling:gatling-http:3.2.0`
import $ivy.`io.gatling:gatling-app:3.2.0`
import $ivy.`io.gatling.highcharts:gatling-charts-highcharts:3.2.0`
import $ivy.`ch.qos.logback:logback-classic:1.2.3`


import io.gatling.app.Gatling
import io.gatling.core.config.GatlingPropertiesBuilder
import io.gatling.core.Predef._
import io.gatling.http.Predef._
import scala.concurrent.duration._
import org.slf4j.{LoggerFactory, Logger}


val rootLogger = LoggerFactory.getLogger(Logger.ROOT_LOGGER_NAME).asInstanceOf[ch.qos.logback.classic.Logger]
rootLogger.setLevel(ch.qos.logback.classic.Level.ERROR)


class SamplePerformanceTest extends Simulation {

  def config = {
    http
      .baseUrl("http://localhost:9900")
  }

  def assertions = List(
    global.responseTime.mean.lt(20),
    global.successfulRequests.percent.gt(95)
  )

  def scn =
    scenario("Simple load").during(10 minutes) {
  feed(csv("./users-query.csv").random)
	.exec(http("search")
          .post("/search?${uuid}&${query}")
          .body(StringBody("""{"user":"${user}","searchQuery":"${query}"}""")).asJson
          .check(status.is(200)) )
    }

  setUp(scn.inject(atOnceUsers(1)))
        .throttle(jumpToRps(200),holdFor(10 minutes)) //This line limits the max requests per second to 200
    .protocols(config)
    .assertions(assertions)
}

val props =
  new GatlingPropertiesBuilder()
    .simulationClass(classOf[SamplePerformanceTest].getName)
    .resultsDirectory("/tmp")
    .build

Gatling.fromMap(props)