Unit testing EssentialAction

When we are trying to test an essential action the status is always 500

val a = EssentialAction { request =>
 Action { Ok("") }(request)
}
Helpers.await(a(FakeRequest()).run).header.status must be equalTo OK

Is it a bug?

[yanns]

Sorry, I do not want to be rude, but I am not happy with the answer.

The question was about unit testing, and starting a FakeApplication is not an optimal way to unit test. FakeApplication is intended to be used in functional tests: http://www.playframework.com/documentation/2.2.x/ScalaTest

On my opinion, starting a FakeApplication for an unit test is not a viable solution because:

• it makes the test much slower
• the test cannot be run in parallel anymore

And I do not really understand why a such difference between Action and EssentialAction.

For example, it is very easy to unit test an Action, even if it consumes a body:

    val action = Action { request =>
      val value = (request.body.asJson.get \ "field").as[String]
      Ok(value)
    }

    val request = FakeRequest(POST, "/")
      .withJsonBody(Json.parse("""{ "field": "value" }"""))
    val result = action.apply(request)
    assert(status(result) === OK)
    assert(contentAsString(result) === "value")

(scala test)

By simply changing the type of the Action, it is much more complicated:

    val action: EssentialAction = Action { request =>
      val value = (request.body.asJson.get \ "field").as[String]
      Ok(value)
    }

    val request = FakeRequest(POST, "/")
      .withHeaders(CONTENT_TYPE -> "application/json")

    val requestBody = Enumerator("""{ "field": "value" }""".getBytes) andThen Enumerator.eof
    Play.start(FakeApplication())
    try {
      val result: Future[SimpleResult] = requestBody |>>> action(request)

      assert(status(result) === OK)
      assert(contentAsString(result) === "value")
    } finally {
      Play.stop()
    }

On my opinion:

• it should be possible to unit test an EssentialAction without any started FakeApplication
• there should be an API to easily unit test an EssentialAction.
• it should be documented how to unit test an EssentialAction.

That would help this framework to be even more awesome for testing.

[yanns]

@jroper PR: https://github.com/playframework/playframework/pull/2086

Feedback welcome.