Akka/Scala example source code file (ThrottleModeSpec.scala)

This example Akka source code file (ThrottleModeSpec.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Akka and Scala source code examples by using tags.

All credit for the original source code belongs to akka.io; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Akka tags/keywords

akka, akkaspec, long, remote, test, testing, testkit, throttlemode, throttlemodespec, tokenbucket, transport, unthrottled

The ThrottleModeSpec.scala Akka example source code

package akka.remote.transport

import akka.testkit.AkkaSpec
import akka.remote.transport.ThrottlerTransportAdapter.{ TokenBucket, Unthrottled }
import java.util.concurrent.TimeUnit

class ThrottleModeSpec extends AkkaSpec {

  val halfSecond: Long = TimeUnit.MILLISECONDS.toNanos(500)

  "ThrottleMode" must {

    "allow consumption of infinite amount of tokens when untrhottled" in {
      val bucket = Unthrottled
      bucket.tryConsumeTokens(0, 100) should be((Unthrottled, true))
      bucket.tryConsumeTokens(100000, 1000) should be((Unthrottled, true))
      bucket.tryConsumeTokens(1000000, 10000) should be((Unthrottled, true))
    }

    "in tokenbucket mode allow consuming tokens up to capacity" in {
      val bucket = TokenBucket(capacity = 100, tokensPerSecond = 100, nanoTimeOfLastSend = 0L, availableTokens = 100)
      val (bucket1, success1) = bucket.tryConsumeTokens(nanoTimeOfSend = 0L, 10)
      bucket1 should be(TokenBucket(100, 100, 0, 90))
      success1 should be(true)

      val (bucket2, success2) = bucket1.tryConsumeTokens(nanoTimeOfSend = 0L, 40)
      bucket2 should be(TokenBucket(100, 100, 0, 50))
      success2 should be(true)

      val (bucket3, success3) = bucket2.tryConsumeTokens(nanoTimeOfSend = 0L, 50)
      bucket3 should be(TokenBucket(100, 100, 0, 0))
      success3 should be(true)

      val (bucket4, success4) = bucket3.tryConsumeTokens(nanoTimeOfSend = 0, 1)
      bucket4 should be(TokenBucket(100, 100, 0, 0))
      success4 should be(false)
    }

    "accurately replenish tokens" in {
      val bucket = TokenBucket(capacity = 100, tokensPerSecond = 100, nanoTimeOfLastSend = 0L, availableTokens = 0)
      val (bucket1, success1) = bucket.tryConsumeTokens(nanoTimeOfSend = 0L, 0)
      bucket1 should be(TokenBucket(100, 100, 0, 0))
      success1 should be(true)

      val (bucket2, success2) = bucket1.tryConsumeTokens(nanoTimeOfSend = halfSecond, 0)
      bucket2 should be(TokenBucket(100, 100, halfSecond, 50))
      success2 should be(true)

      val (bucket3, success3) = bucket2.tryConsumeTokens(nanoTimeOfSend = 2 * halfSecond, 0)
      bucket3 should be(TokenBucket(100, 100, 2 * halfSecond, 100))
      success3 should be(true)

      val (bucket4, success4) = bucket3.tryConsumeTokens(nanoTimeOfSend = 3 * halfSecond, 0)
      bucket4 should be(TokenBucket(100, 100, 3 * halfSecond, 100))
      success4 should be(true)
    }

    "accurately interleave replenish and consume" in {
      val bucket = TokenBucket(capacity = 100, tokensPerSecond = 100, nanoTimeOfLastSend = 0L, availableTokens = 20)
      val (bucket1, success1) = bucket.tryConsumeTokens(nanoTimeOfSend = 0L, 10)
      bucket1 should be(TokenBucket(100, 100, 0, 10))
      success1 should be(true)

      val (bucket2, success2) = bucket1.tryConsumeTokens(nanoTimeOfSend = halfSecond, 60)
      bucket2 should be(TokenBucket(100, 100, halfSecond, 0))
      success2 should be(true)

      val (bucket3, success3) = bucket2.tryConsumeTokens(nanoTimeOfSend = 2 * halfSecond, 40)
      bucket3 should be(TokenBucket(100, 100, 2 * halfSecond, 10))
      success3 should be(true)

      val (bucket4, success4) = bucket3.tryConsumeTokens(nanoTimeOfSend = 3 * halfSecond, 70)
      bucket4 should be(TokenBucket(100, 100, 2 * halfSecond, 10))
      success4 should be(false)
    }

    "allow oversized packets through by loaning" in {
      val bucket = TokenBucket(capacity = 100, tokensPerSecond = 100, nanoTimeOfLastSend = 0L, availableTokens = 20)
      val (bucket1, success1) = bucket.tryConsumeTokens(nanoTimeOfSend = 0L, 30)
      bucket1 should be(TokenBucket(100, 100, 0, 20))
      success1 should be(false)

      val (bucket2, success2) = bucket1.tryConsumeTokens(nanoTimeOfSend = halfSecond, 110)
      bucket2 should be(TokenBucket(100, 100, halfSecond, -40))
      success2 should be(true)

      val (bucket3, success3) = bucket2.tryConsumeTokens(nanoTimeOfSend = 2 * halfSecond, 20)
      bucket3 should be(TokenBucket(100, 100, halfSecond, -40))
      success3 should be(false)

      val (bucket4, success4) = bucket3.tryConsumeTokens(nanoTimeOfSend = 3 * halfSecond, 20)
      bucket4 should be(TokenBucket(100, 100, 3 * halfSecond, 40))
      success4 should be(true)
    }

  }

}