Functional Tests in Play 2.4.6 when using compile time DI - scala

Question

I'm using Play 2.4.6 with compile time dependency injection and ScalaTest. The controller's constructor has few parameters, and in an ApplicationLoader I create it.
Here is the code:
class BootstrapLoader extends ApplicationLoader {
def load(context: Context) = {
new AppComponents(context).application
}
}
class AppComponents(context: Context) extends BuiltInComponentsFromContext(context) with NingWSComponents {
lazy val router = new Routes(httpErrorHandler, authenticationController, applicationController, assets)
lazy val applicationController = new controllers.Application()
lazy val authenticationController = new controllers.Authentication()(configuration, wsApi.client)
lazy val assets = new controllers.Assets(httpErrorHandler)
}
class Authentication(implicit configuration: Configuration, val ws: WSClient) extends Controller {
def login = Action { implicit request =>
Unauthorized(s"${redirectUrl}")
}
}
class AuthenticationSpec extends PlaySpec with OneAppPerSuite {
implicit val configuration: Configuration = app.configuration
implicit val wsClient: WSClient = WS.client(app)
"when user not logged-in" should {
"return Status code Unauthorized(401) with redirect url" in {
1 mustEqual 2
}
}
}
When I'm running the test I'm getting the following error:
[info] Exception encountered when attempting to run a suite with class name: controllers.AuthenticationSpec *** ABORTED ***
[info] com.google.inject.ProvisionException: Unable to provision, see the following errors:
[info]
[info] 1) Could not find a suitable constructor in controllers.Authentication. Classes must have either one (and only one) constructor annotated with #Inject or a zero-argument constructor that is not private.
[info] at controllers.Authentication.class(Authentication.scala:19)
[info] while locating controllers.Authentication
[info] for parameter 1 at router.Routes.<init>(Routes.scala:35)
[info] while locating router.Routes
[info] while locating play.api.test.FakeRouterProvider
[info] while locating play.api.routing.Router
[info]
[info] 1 error
[info] at com.google.inject.internal.InjectorImpl$2.get(InjectorImpl.java:1025)
[info] at com.google.inject.internal.InjectorImpl.getInstance(InjectorImpl.java:1051)
[info] at play.api.inject.guice.GuiceInjector.instanceOf(GuiceInjectorBuilder.scala:321)
[info] at play.api.inject.guice.GuiceInjector.instanceOf(GuiceInjectorBuilder.scala:316)
[info] at play.api.Application$class.routes(Application.scala:112)
[info] at play.api.test.FakeApplication.routes(Fakes.scala:197)
[info] at play.api.Play$$anonfun$start$1.apply$mcV$sp(Play.scala:90)
[info] at play.api.Play$$anonfun$start$1.apply(Play.scala:87)
[info] at play.api.Play$$anonfun$start$1.apply(Play.scala:87)
[info] at play.utils.Threads$.withContextClassLoader(Threads.scala:21)
FakeApplication use GuiceApplicationBuilder, which of course does not work.
What should I do to run such tests?
Thanks

Answer 1

override implicit lazy val app = new BootstrapLoader().load(
ApplicationLoader.createContext(
new Environment(
new File("."), ApplicationLoader.getClass.getClassLoader, Mode.Test)))
It works in Play 2.5.1

Answer 2

You are getting an error because the tests are not even able to start a application. That is happening because you are using Dependency Injection in your controllers (as the error message suggests) and you need to declare them as classes, instead of as objects. As you can see at the docs:
package controllers
import play.api.mvc._
class Application extends Controller {
def index = Action {
Ok("It works!")
}
}
If your controller has some dependency to be injected, you should use the #Inject annotation in your controller constructor (again, please see the docs). Per instance:
package controllers
import play.api.mvc._
import play.api.libs.ws._
import javax.inject._
class Application #Inject() (ws: WSClient) extends Controller {
// ...
}
You can also read the Compile Time Dependency Injection docs if you are using it instead of runtime DI.

Answer 3

If you use specs2 you can do it. see http://loicdescotte.github.io/posts/play24-compile-time-di/
But you loose the nice api.
Scalatest / scalatest-plus has done something funky with the DI (guice) :(

Answer 4

I'm facing the same problem as you. I don't have a satisfying solution, the following is a mere workaround:
I ended up putting
implicit def client:WSClient = NingWSClient()
in my WithApplicationLoader class
I also found https://github.com/leanovate/play-mockws which allows you to mock ws calls. But that's not what we want here.

Answer 5

my guess would be that the OneAppPerSuite trait isn't using your custom application loader. you may need to override the application construction that comes from that trait and make it use your custom loader.
looks like there is an example using scalatest here: http://mariussoutier.com/blog/2015/12/06/playframework-2-4-dependency-injection-di/