Obtain the URI of a Controller method call - scala

Question

I'm writing a Play 2.3.2 application in Scala.
In my application I'm writing a method that call an other controller method like the following:
def addTagToUser = CorsAction.async { request =>
implicit val userRestFormat = UserFormatters.restFormatter
implicit val inputFormat = InputFormatters.restFormatter
implicit val outputWriter = OutputFormatters.restWriter
//update the tag of a user
def updateTagToUserDB(value: JsValue): Future[Boolean] = {
val holder : WSRequestHolder = WS.url("http://localhost:9000/recommendation/ advise")
val complexHolder = holder.withHeaders("Content-Type" -> "application/json")
complexHolder.post(value).map(response => response.status match {//handle the response
case 200 => true
case _ => false
}
)
}
val jsonData = request.body.asJson //get the json data
jsonData match {
case Some(x) => x.validate[Input] match {
case JsSuccess(input, _) => updateTagToUserDB(x).flatMap(status => status match {
case true => Future{Ok}
case _ => Future{InternalServerError("Error on update the users tags")}
})
case e: JsError => Future{BadRequest("json bad formed")}
}
case None => Future{BadRequest("need a json value")}
}
}
But in this code I've the problem that the url is create static, Is possible to get the absolute uri of a Controller method in Play??
How can I make that??

Answer 1

As mentioned in reverse routing section of Play docs, you can achieve this with the following method call:
routes.Application.advise()
Note that routes exists in controllers so if you are in controllers package you can simply access reverse routes with routes.ControllerName.methodName.
From other parts of the code you need to use the fully qualified package, i.e. controllers.reverse.Application.advise().
If controller method takes a parameter you need to pass the desired argument and get the actual route, for example routes.Application.someMethod(10).
Reverse routing is a powerful asset in Play toolbox which frees you from repeating yourself. It's future proof in a sense that if you change your route, the change will be reflected automatically to the whole application.
Alternative
This approach may not be the best approach.
Redirecting to another controller makes sense, but sending a request to another controller which resides just inside the same web app is overkill and unnecessary. It would be more wise if your web app serves responses to outside not to request a response from itself.
You can easily avoid it by putting the common logic somewhere else and use it from both controllers. According to best practices a good controller is a thin one! By better layering life will be much easier.