Finagle client in Scala Play Controller

Question

I'm using a method(FinagleClient.longRunningComputation) of Finagle client in my controller

def alfa = Action.async(parse.json) { request =>

    val response = FinagleClient.longRunningComputation(request.body )          
    response.map( rest => Ok("Got result: " + rest ))

}

I need to get the result of the com.twitter.util.Future in my play Controller

I try using Returning futures , but the compiler, return the following error:

found   : com.twitter.util.Future[play.api.mvc.Result]
required: scala.concurrent.Future[play.api.mvc.Result]

response.map(rest => Ok("Got result: " + rest))

I need to use a com.twitter.util.Future in my play Controller

How Can I Do This?

Answer 1

You will have to convert to scala.concurrent.Future, which you can do using Promise.

Something like this:

def alfa = Action.async(parse.json) { request =>
    val p = Promise[Result]
    val response = FinagleClient.longRunningComputation(request.body )          
    val twitterFuture = response.map( rest => Ok("Got result: " + rest ))
    twitterFuture.onSuccess(p.success)
    twitterFuture.onFailure(p.failure)

    p.future
}

We can generalize this to implicitly convert com.twitter.util.Future[A] to scala.concurrent.Future[A].

import com.twitter.util.{Future => TwitterFuture}
import scala.concurrent.{Future, Promise}

object TwitterConversions {
    def twitter2Scala[A](f: TwitterFuture[A]): Future[A] = {
        val p = Promise[A]
        f.onSuccess(p.success)
        f.onFailure(p.failure)
        p.future
    }
}

Then all you would need to do in your controller is import TwitterConversions._ (or whatever package you put it in).