How to perform unit test in controller? - scala

Question

Let say, i have controller like the following:
class JenisKejahatanControl #Inject()(service: JenisKejahatanService, val messagesApi: MessagesApi) extends Controller with I18nSupport {
def add = Action.async { implicit request =>
lazy val incoming = JenisKejahatan.formJenisK.bindFromRequest()
incoming.fold( error => {
lazy val response = ErrorResponse(BAD_REQUEST, messagesApi("request.error"))
Future.successful(BadRequest(Json.toJson(response)))
}, { newJenisK =>
lazy val future = service.addJenisK(newJenisK)
future.flatMap {
case Some(jenis) => Future.successful(Created(Json.toJson(SuccessResponse(jenis))))
case None => Future.successful(BadRequest(Json.toJson(ErrorResponse(NOT_FOUND, messagesApi("add.jenis.kejahatan.fail")))))
}
})
}
}
and the i want to test my def add using specs2, how to do it?

Answer 1

Since your controller has injected components the bit I assume that one bit you're missing is how to obtain an instance of it in your spec with the various dependencies satisfied. For this you can use the GuiceApplicationBuilder to obtain a Play application instance, and then use its injector to get an instance of your controller without having to construct it manually (more dependency injection docs here and specifically about testing with Guice here.)
If you can construct your controller manually, as in the example, that's great and makes things simpler, but controllers tend to have non-trivial dependencies which you will most likely want to mock using the overrides method on the GuiceApplicationBuilder.
With an instance of your controller constructed, it's then really simple to "apply" a mock (fake) request to your action methods and determine that they give the status and body you expect. Here's an example:
import controllers.{SuccessResponse, JenisKejahatanControl}
import play.api.inject.guice.GuiceApplicationBuilder
import play.api.inject.bind
import play.api.mvc.Result
import play.api.test.{FakeRequest, PlaySpecification}
import scala.concurrent.Future
class JenisKejahatanControlSpec extends PlaySpecification {
"JenisKejahatanControl#add" should {
"be valid" in {
// Build an instance of a Play application using the
// default environment and configuration, and use it
// to obtain an instance of your controller with the
// various components injected.
val jenisController = new GuiceApplicationBuilder()
.overrides( // Mock the data service
bind[JenisKejahatanService]
.toInstance(new MockJenisKejahatanService))
.build()
.injector
.instanceOf[JenisKejahatanControl]
// Create a "fake" request instance with the appropriate body data
val request = FakeRequest().withFormUrlEncodedBody("name" -> "test")
// Apply the request to your action to obtain a response
val eventualResult: Future[Result] = jenisController.add.apply(request)
// Check the status of the response
status(eventualResult) must_== CREATED
// Ensure the content of the response is as-expected
contentAsJson(eventualResult).validate[SuccessResponse].asOpt must beSome.which { r =>
r.jenis.name must_== "test"
}
}
}
}