Play 2.0.1 and setting Access-Control-Allow-Origin

Question

I have a Play 2.0.1 application that I want to call using Javascript hosted on other domains. My Javascript call is failing with:

Origin http://mydomain.com is not allowed by Access-Control-Allow-Origin.

I have found a number of examples of how to set the correct HTTP header in Play 1, but have not found anything for Play 2.0.1. After reading the documentation (http://www.playframework.org/documentation/2.0.2/JavaResponse) I've tried the following just to get things working:

public static Result myJsonWebService() {
  ...
  response().setHeader("Access-Control-Allow-Origin", "*");
  return ok(toJson(jsonObject));
}

but my JS web service call is still failing.

What do I need to do to get this working?

Answer 1

Just for Scala guys, this is the implementation I'm currently using:

import play.api.mvc._
import scala.concurrent._
import play.api.http.HeaderNames._

/**
 * Action decorator that provide CORS support
 *
 * @author Giovanni Costagliola, Nick McCready
 */
case class WithCors(httpVerbs: String*)(action: EssentialAction) extends EssentialAction with Results {
    def apply(request: RequestHeader) = {
        implicit val executionContext: ExecutionContext = play.api.libs.concurrent.Execution.defaultContext
        val origin = request.headers.get(ORIGIN).getOrElse("*")
        if (request.method == "OPTIONS") { // preflight
            val corsAction = Action {
                request =>
                    Ok("").withHeaders(
                        ACCESS_CONTROL_ALLOW_ORIGIN -> origin,
                        ACCESS_CONTROL_ALLOW_METHODS -> (httpVerbs.toSet + "OPTIONS").mkString(", "),
                        ACCESS_CONTROL_MAX_AGE -> "3600",
                        ACCESS_CONTROL_ALLOW_HEADERS ->  s"$ORIGIN, X-Requested-With, $CONTENT_TYPE, $ACCEPT, $AUTHORIZATION, X-Auth-Token",
                        ACCESS_CONTROL_ALLOW_CREDENTIALS -> "true")
            }
            corsAction(request)
        } else { // actual request
            action(request).map(res => res.withHeaders(
                ACCESS_CONTROL_ALLOW_ORIGIN -> origin,
                ACCESS_CONTROL_ALLOW_CREDENTIALS -> "true"
            ))
        }
    }
}

To use it just decorate your action in the following way:

def myAction = WithCors("GET", "POST") {
  Action { request =>
    ???
  }
}