Add more realistic test scenario and bump versions

Author: pbernet

build.sbt

@@ -19,11 +19,11 @@ val keycloakVersion = "26.0.1"
 val sttpVersion = "3.10.1"
 val influxdbVersion = "7.1.0"
 val awsClientVersion = "2.25.32"
-val gatlingVersion = "3.12.0"
+val gatlingVersion = "3.13.1"
 val circeVersion = "0.14.8"
 
 libraryDependencies ++= Seq(
-  "org.scala-lang.modules" %% "scala-parallel-collections" % "1.0.4",
+  "org.scala-lang.modules" %% "scala-parallel-collections" % "1.1.0",
 
   "org.apache.pekko" %% "pekko-stream" % pekkoVersion,
   "org.apache.pekko" %% "pekko-stream-typed" % pekkoVersion,
@@ -124,7 +124,7 @@ libraryDependencies ++= Seq(
   "org.testcontainers" % "localstack" % testContainersVersion,
   "org.testcontainers" % "clickhouse" % testContainersVersion,
 
-  "com.clickhouse" % "clickhouse-jdbc" % "0.6.1",
+  "com.clickhouse" % "clickhouse-jdbc" % "0.6.5",
   "com.crobox.clickhouse" %% "client" % "1.2.2",
 
   "org.opensearch" % "opensearch-testcontainers" % "2.0.1",
@@ -140,8 +140,8 @@ libraryDependencies ++= Seq(
   "org.jboss.spec.javax.ws.rs" % "jboss-jaxrs-api_2.1_spec" % "2.0.2.Final",
 
   "org.postgresql" % "postgresql" % "42.7.4",
-  "io.zonky.test.postgres" % "embedded-postgres-binaries-bom" % "16.4.0" % Test pomOnly(),
-  "io.zonky.test" % "embedded-postgres" % "2.0.7" % Test,
+  "io.zonky.test.postgres" % "embedded-postgres-binaries-bom" % "16.6.0" % Test pomOnly(),
+  "io.zonky.test" % "embedded-postgres" % "2.1.0" % Test,
 
   "org.scalatest" %% "scalatest" % "3.2.18" % Test,
   "org.apache.pekko" %% "pekko-testkit" % pekkoVersion % Test,

project/plugins.sbt

@@ -4,4 +4,4 @@ addSbtPlugin("ch.epfl.scala" % "sbt-scalafix" % "0.12.1")
 //addDependencyTreePlugin
 
 // https://docs.gatling.io/reference/integrations/build-tools/sbt-plugin
-addSbtPlugin("io.gatling" % "gatling-sbt" % "4.10.1")
+addSbtPlugin("io.gatling" % "gatling-sbt" % "4.10.2")

src/main/scala/akkahttp/ReverseProxy.scala

@@ -46,7 +46,8 @@ import scala.util.{Failure, Success}
   * Remarks:
   *  - The target server selection is via the "Host" HTTP header
   *  - Local/Remote target servers are designed to be flaky to show Retry/CircuitBreaker behavior
-  *  - On top of the built-in client, you may also try other clients
+  *    eg for Local adjust [[responseCodes]]
+  *  - On top of the built-in client, you may also try other clients, see below
   *  - This PoC may not scale well, possible bottlenecks are:
   *     - Combination of Retry/CircuitBreaker
   *     - Round robin impl. with `requestCounter` means shared state
@@ -93,9 +94,12 @@ object ReverseProxy extends App {
     )
   )
 
-  localTargetServers(maxConnections = 5) // 1-1024
+  // For Mode.local: Adjust to provoke more retries on ReverseProxy
+  val responseCodes = List(200, 200, 200, 200, 200, 200, 200, 200, 500, 503)
+
+  localTargetServers(maxConnections = 100) // 1-1024
   reverseProxy()
-  // Switch here to force ReverseProxy to forward requests to local or remote target server(s)
+  // Switch here to force ReverseProxy to forward requests to local/remote target server(s)
   clients(nbrOfClients = 10, requestsPerClient = 10, Mode.local)
 
   // HTTP client(s)
@@ -233,11 +237,9 @@ object ReverseProxy extends App {
           Thread.sleep(500)
           val id = request.getHeader("X-Correlation-ID").orElse(RawHeader("X-Correlation-ID", "N/A")).value()
 
-          // Adjust to provoke more retries on ReverseProxy
-          val codes = List(200, 200, 200, 500, 500, 500)
-          val randomResponse = codes(new scala.util.Random().nextInt(codes.length))
-          logger.info(s"Target server: ${request.uri.authority.host}:${request.uri.effectivePort} got echo request with id: $id, reply with: $randomResponse")
-          (StatusCode.int2StatusCode(randomResponse), Seq(RawHeader("X-Correlation-ID", id)))
+          val randomResponseCode = responseCodes(new scala.util.Random().nextInt(responseCodes.length))
+          logger.info(s"Target server: ${request.uri.authority.host}:${request.uri.effectivePort} got echo request with id: $id, reply with: $randomResponseCode")
+          (StatusCode.int2StatusCode(randomResponseCode), Seq(RawHeader("X-Correlation-ID", id)))
         }
       }
 

src/test/scala/ReverseProxySimulation.scala

@@ -38,10 +38,45 @@ class ReverseProxySimulation extends Simulation {
         .exec(session => session.set("correlationId", session("correlationId").as[Int] + 1))
     }
 
-  setUp(
-    scn.inject(
-      atOnceUsers(10),
-      rampUsers(50).during(30.seconds)
+  // Adjust to scale load
+  val loadFactorMorning = 0.01
+  val loadFactorMidday = 0.02
+  val loadFactorEvening = 0.03
+
+  val morningPeak = scenario("Morning Peak")
+    .exec(scn)
+    .inject(
+      nothingFor(5.seconds), // initial quiet period
+      rampUsers((20 * loadFactorMorning).toInt).during(10.seconds), // ramp up
+      constantUsersPerSec(50 * loadFactorMorning).during(20.seconds), // peak load
+      rampUsersPerSec(50 * loadFactorMorning).to(10 * loadFactorMorning).during(10.seconds), // ramp down
+      constantUsersPerSec(10 * loadFactorMorning).during(10.seconds), // tail off
+      nothingFor(30.seconds) // cool down period
+    )
+
+  val middayPeak = scenario("Midday Peak")
+    .exec(scn)
+    .inject(
+      nothingFor(5.seconds),
+      rampUsers((20 * loadFactorMidday).toInt).during(10.seconds),
+      constantUsersPerSec(50 * loadFactorMidday).during(20.seconds),
+      rampUsersPerSec(50 * loadFactorMidday).to(10 * loadFactorMidday).during(10.seconds),
+      constantUsersPerSec(10 * loadFactorMidday).during(10.seconds),
+      nothingFor(30.seconds)
     )
+
+  val eveningPeak = scenario("Evening Peak")
+    .exec(scn)
+    .inject(
+      nothingFor(5.seconds),
+      rampUsers((20 * loadFactorEvening).toInt).during(10.seconds),
+      constantUsersPerSec(50 * loadFactorEvening).during(20.seconds),
+      rampUsersPerSec(50 * loadFactorEvening).to(10 * loadFactorEvening).during(10.seconds),
+      constantUsersPerSec(10 * loadFactorEvening).during(10.seconds),
+      nothingFor(30.seconds)
+    )
+
+  setUp(
+    morningPeak.andThen(middayPeak).andThen(eveningPeak)
   ).protocols(httpProtocol)
 }