如何测试客户端Akka HTTP

Question

我刚刚开始测试Akka HTTP请求级客户端API(基于未来).我一直在努力弄清楚的一件事是如何为此编写单元测试.有没有办法模拟响应并在不必实际执行HTTP请求的情况下完成未来？

我正在查看API和testkit包,试图看看我如何使用它,只是在文档中找到它实际上说的:

akka-http-testkit用于验证服务器端服务实现的测试工具和实用程序集

我正在思考一些事情TestServer(有点像TestSourceAkka Streams),并使用服务器端路由DSL来创建预期的响应,并以某种方式将其挂钩到Http对象上.

以下是我想要测试的函数的简化示例:

object S3Bucket {

  def sampleTextFile(uri: Uri)(
    implicit akkaSystem: ActorSystem,
    akkaMaterializer: ActorMaterializer
  ): Future[String] = {
    val request = Http().singleRequest(HttpRequest(uri = uri))
    request.map { response => Unmarshal(response.entity).to[String] }
  }
}

Answer 1

我认为，总的来说，您已经想到了最好的方法是模拟响应。在Scala中，可以使用Scala Mock http://scalamock.org/完成。

如果您安排代码以便将您的实例akka.http.scaladsl.HttpExt依赖注入到使用它的代码中（例如，作为构造函数参数），那么在测试期间，您可以注入的实例，mock[HttpExt]而不是使用Httpapply方法构建的实例。

编辑：我想这是因为不够具体而被否决。这是我如何模拟您的方案。所有的隐式函数使它变得更加复杂。

代码在main：

import akka.actor.ActorSystem
import akka.http.scaladsl.Http
import akka.http.scaladsl.model.{Uri, HttpResponse, HttpRequest}
import akka.http.scaladsl.unmarshalling.Unmarshal
import akka.stream.ActorMaterializer

import scala.concurrent.{ExecutionContext, Future}

trait S3BucketTrait {

  type HttpResponder = HttpRequest => Future[HttpResponse]

  def responder: HttpResponder

  implicit def actorSystem: ActorSystem

  implicit def actorMaterializer: ActorMaterializer

  implicit def ec: ExecutionContext

  def sampleTextFile(uri: Uri): Future[String] = {

    val responseF = responder(HttpRequest(uri = uri))
    responseF.flatMap { response => Unmarshal(response.entity).to[String] }
  }
}

class S3Bucket(implicit val actorSystem: ActorSystem, val actorMaterializer: ActorMaterializer) extends S3BucketTrait {

  override val ec: ExecutionContext = actorSystem.dispatcher

  override def responder = Http().singleRequest(_)
}

代码在test：

import akka.actor.ActorSystem
import akka.http.scaladsl.model._
import akka.stream.ActorMaterializer
import akka.testkit.TestKit
import org.scalatest.{BeforeAndAfterAll, WordSpecLike, Matchers}
import org.scalamock.scalatest.MockFactory
import scala.concurrent._
import scala.concurrent.duration._
import scala.concurrent.Future

class S3BucketSpec extends TestKit(ActorSystem("S3BucketSpec"))
with WordSpecLike with Matchers with MockFactory with BeforeAndAfterAll  {


  class MockS3Bucket(reqRespPairs: Seq[(Uri, String)]) extends S3BucketTrait{

    override implicit val actorSystem = system

    override implicit val ec = actorSystem.dispatcher

    override implicit val actorMaterializer = ActorMaterializer()(system)

    val mock = mockFunction[HttpRequest, Future[HttpResponse]]

    override val responder: HttpResponder = mock

    reqRespPairs.foreach{
      case (uri, respString) =>
        val req = HttpRequest(HttpMethods.GET, uri)
        val resp = HttpResponse(status = StatusCodes.OK, entity = respString)
        mock.expects(req).returning(Future.successful(resp))
    }
  }

  "S3Bucket" should {

    "Marshall responses to Strings" in {
      val mock = new MockS3Bucket(Seq((Uri("http://example.com/1"), "Response 1"), (Uri("http://example.com/2"), "Response 2")))
      Await.result(mock.sampleTextFile("http://example.com/1"), 1 second) should be ("Response 1")
      Await.result(mock.sampleTextFile("http://example.com/2"), 1 second) should be ("Response 2")
    }
  }

  override def afterAll(): Unit = {
    val termination = system.terminate()
    Await.ready(termination, Duration.Inf)
  }
}

build.sbt 依赖项：

libraryDependencies += "com.typesafe.akka" % "akka-http-experimental_2.11" % "2.0.1"

libraryDependencies += "org.scalamock" %% "scalamock-scalatest-support" % "3.2" % "test"

libraryDependencies += "org.scalatest" % "scalatest_2.11" % "2.2.6"

libraryDependencies += "com.typesafe.akka" % "akka-testkit_2.11" % "2.4.1"