Skip to content

Latest commit

 

History

History
83 lines (63 loc) · 2.8 KB

testing_guide.md

File metadata and controls

83 lines (63 loc) · 2.8 KB

Testing Guide

Getting started

TestKit that is described by this doc requires following module. Please add the dependency to your project.

libraryDependencies ++= Seq(
  "com.typesafe.akka" %% "akka-actor-testkit-typed" % akkaVersion % Test
)

ReplicatedEntityBehaviorTestKit

To unit test ReplicatedEntityBehavior, you can use ReplicatedEntityBehaviorTestKit. It makes the behavior run a command, and you can assert the returned result is as expected. The result contains the following elements:

  • The event emitted by the command
  • New state after applying the events
  • Reply message to a command (if the command provides it)

The TestKit verifies serialization of commands, events and state automatically.

To test restoring the behavior, you can use ReplicatedEntityBehaviorTestKit.restart() method. It will restart the behavior, and then recover the state from stored snapshot and events from commands that are processed.

Following example is a test for the BankAccountBehavior which is shown in the Implementation Guide:

class BankAccountBehaviorSpec extends AnyWordSpecLike with Matchers with BeforeAndAfterEach with BeforeAndAfterAll {

  import BankAccountBehavior._

  private[this] val testKit = ActorTestKit()

  private[this] val bankAccountTestKit =
    ReplicatedEntityBehaviorTestKit[Command, DomainEvent, Account](
      testKit.system,
      BankAccountBehavior.TypeKey,
      entityId = "test-entity",
      behavior = context => BankAccountBehavior(context),
    )

  override def afterEach(): Unit = {
    bankAccountTestKit.clear()
    super.afterEach()
  }

  override def afterAll(): Unit = {
    testKit.shutdownTestKit()
    super.afterAll()
  }

  "A BankAccountBehavior" should {

    "increase a balance when it receives Deposit" in {
      val transactionId1 = 1L
      val result1        = bankAccountTestKit.runCommand(Deposit(transactionId1, amount = 1000, _))
      result1.eventOfType[Deposited].amount should be(1000)
      result1.state.balance should be(1000)
      result1.reply.balance should be(1000)

      val transactionId2 = 2L
      val result2        = bankAccountTestKit.runCommand(Deposit(transactionId2, amount = 2000, _))
      result2.eventOfType[Deposited].amount should be(2000)
      result2.state.balance should be(3000)
      result2.reply.balance should be(3000)
    }
    
    "restore the balance after it restarts" in {
      val result1 = bankAccountTestKit.runCommand(Deposit(transactionId = 1L, amount = 1000, _))
      result1.reply.balance should be(1000)
      val result2 = bankAccountTestKit.runCommand(Withdraw(transactionId = 2L, amount = 500, _))
      result2.replyOfType[WithdrawSucceeded].balance should be(500)

      bankAccountTestKit.restart()
      bankAccountTestKit.state.balance should be(500)
    }
  }
}