Akka http - complete with headers

[Giovanni Alberto Caporaletti]

Hi,

Completing a route with a Tuple3[StatusCode, Seq[HttpHeader], T]  doesn't seem to work for me. My json4s marshaller serializes the whole tuple as an object. Tuple2[StatusCode, T] works instead.

Are there any plans to implement it?

What's the best way to add headers to a response anyway? In my case the header depends on a future (or, well, on a materialization of a stream). 

Thank you

Cheers

G

[Giovanni Alberto Caporaletti]

This is what I came up with (I have another question below):

def onSuccessHead(magnet: OnStreamSuccessHeadMagnet): Directive[magnet.Out] = {
  magnet.directive
}

trait OnStreamSuccessHeadMagnet {
  type Out
  def directive: Directive[Out]
}

object OnStreamSuccessHeadMagnet {
  import akka.http.server.directives.FutureDirectives._

  implicit def apply[T](s: Source[T, _])(implicit mat: ActorFlowMaterializer, tupler: Tupler[T]) = {
    new OnStreamSuccessHeadMagnet {
      type Out = tupler.Out
      val directive = onSuccess(s.runWith(Sink.head("SourceMarshallerHeadSink")): Future[T])
    }
  }

}

and the route:

onSuccessHead(userService.createUser(req)) { newUser =>
  respondWithHeader(Location(s"/$v1/$user/${newUser.id}")) {
    complete(Created -> newUser)
  }
}

By the way, is there a way of extracting "constant" paths? e.g. my path is path("v1" / "user") but I don't want to have separate constants for v1 and user and something like path("some" / "path") { (some, path) => ...} doesn't work. In other words, how do you do reverse routing in spray/akka http?

Thanks

G

[Mark Hatton]

Completing a route with a Tuple3[StatusCode, Seq[HttpHeader], T]  doesn't seem to work for me.

Ensure your headers collection is an instance of immutable.Seq.  E.g.:

import collection.immutable._

complete( (OK, Seq(`Cache-Control`(`no-cache`)), responseEntity) )

Works for me.

Mark

 

[Giovanni Alberto Caporaletti]

oh! That was it! thanks ;) 

I'll remember to check if they add it to the documentation once it's released. 

Cheers

G