The document discusses testing a REST API built with the Spray toolkit in Scala. It provides an example of building a simple REST service with Spray, including defining routes and request/response handling. It then demonstrates how to test the service using Spray's testkit, including making requests, checking responses, and handling rejections. It recommends testing the REST layer independently of underlying services through dependency injection.

1. testing spray.io
in 45 minutes

2. The Plan
● What spray is
● What we are testing
● How

3. Spray
“an open-source toolkit for building
REST/HTTP-based integration layers on top of
Scala and Akka”

4. Spray
“an open-source toolkit for building
REST/HTTP-based integration layers on top of
Scala and Akka”
Library to wrap services with REST API

5. REST API
● request routing
● (un)marshalling to / from domain objects
● authentication / authorization
● encoding / decoding (compression)
● serving static content
● caching

6. REST API
● request routing - headers, params and paths
● (un)marshalling to / from domain objects - req/resp entity
● authentication / authorization - directives
● encoding / decoding (compression) - Gzip, Deflate
● serving static content - the same way as request routing
● caching - some of

7. Example
libraryDependencies ++= {
val akkaV = "2.3.7"
val sprayV = "1.3.2"
Seq(
"com.typesafe.akka" %% "akka-actor" % akkaV,
"io.spray" %% "spray-can" % sprayV,
"io.spray" %% "spray-routing" % sprayV,
"io.spray" %% "spray-testkit" % sprayV % "test",
"org.scalatest" %% "scalatest" % "2.2.4" % "test")
}

8. Example
import scala.concurrent.duration._
import akka.actor.{Props, ActorSystem}
import akka.io.IO
import akka.pattern.ask
import akka.util.Timeout
import spray.can.Http
object App extends scala.App {
implicit val system = ActorSystem("system")
val service = system.actorOf( Props(new RestService), "rest")
implicit val timeout = Timeout(5.seconds)
IO(Http) ? Http.Bind(service, interface = "localhost", port = 8080)
}

9. Example - not testable
import spray.routing.HttpServiceActor
class RestService extends HttpServiceActor {
def receive = runRoute(route)
def route =
get {
complete( "ok")
}
}

10. Example - extract trait
import spray.routing.HttpService
trait SimpleService extends HttpService {
def simpleRoute =
get {
complete( "ok")
}
}

11. Example - replace route
class RestService extends HttpServiceActor
with SimpleService {
def receive = runRoute(route)
def route =
simpleRoute
}

12. Example - test
import org.scalatest. {Matchers, FlatSpec}
import spray.testkit.ScalatestRouteTest
class SimpleServiceSpec extends FlatSpec with Matchers
with ScalatestRouteTest
with SimpleService {
def actorRefFactory = system // boilerplate
"A SimpleService" should "return 'ok' for GET request on /" in {
Get("/") ~> simpleRoute ~> check {
responseAs[ String] should be ("ok")
}
}
}

13. Test API
status.intValue
headers
responseAs[T] // (un)marshalling - String for free
rejections // little tricky when want to test deeper
Get("/users?format=pretty" )
Post("/user", """{"name": "pawel"}""" )
Put("/user/1", """{"name": "kopiczko"}""" )
Delete("/user/1")
Get("/mail/all") ~> Authorization(BasicHttpCredentials ("pawel", ""))

14. Test Rejection
def deleteRoute =
delete {
path("user" / IntNumber) { id =>
userService.delete(id)
complete( "Deleted user with id " + id)
}
}
Get("/user/1") ~> deleteRoute ~> check {
rejection should be ( MethodRejection (HttpMethods.DELETE))
}
OK, but...

15. Test Rejection
Get("/user/1") ~> deleteRoute ~> check {
status.intValue should be ( 405)
}
[info] - should not allow GET request on /user *** FAILED ***
[info] Request was rejected with List(MethodRejection(DELETE))

16. Test Rejection
Get("/user/1") ~> {
handleRejections( RejectionHandler .Default) {
deleteRoute
}
} ~> check {
status.intValue should be ( 405)
}
OK

17. Dependency Injection
Route is a method - pass arguments
def userRoute(service: UserService) =
get("user" / IntNumber) { id =>
complete {
userService.get(id)
}
}
Get("/user/1") ~> userRoute(userServiceMock) ~> check

18. Dependency Injection
● Test the REST layer responsibility
● Do NOT test underlying services
● There is another place for that

19. http://www.slideshare.net/kopiczko/scala45-spray-test-45539693
http://goo.gl/YuL3On