play framework 2 with scala: pretify json - json

Question

I'm using the play framework 2 native support for json (http://www.playframework.org/documentation/latest/ScalaJson) and I have a JsValue that I'm converting to string to save it to a text file, like this
val json: JsValue = [....]
Json.stringify(json)
Which works fine, but generates something like this:
{"tokens":[{"id":"1000","token":"DON...
I was wondering if there's an easy way to generate a formatted json like this
{
"tokens":
[
{
"id":"1000",
"token":"DON...

Answer 1

I used liftweb JSON package with its Printer object/trait. Works 'pretty' well:
import play.api._
import play.api.mvc._
import play.api.libs._, concurrent._, json._
import com.mongodb.casbah.Imports.{MongoConnection, MongoCursor, WriteConcern}
import com.mongodb.casbah.query.Imports._
import com.novus.salat.json._
import net.liftweb.json.{render => jsonRender, _}
class Application extends Controller {
def getJson(id: String) = Action { implicit request =>
val objPromise = Akka.future(Database.getById(id))
Async {
objPromise.orTimeout("Error", 1000).map { o =>
o.fold(
hit => Ok(hit.map{ o: DBObject => pretty(jsonRender(ToJValue(o)))}.getOrElse("")).as("text/json"),
timeout => InternalServerError(timeout)
)
}
}
}