Helper object to work around S.?(...) working only within a valid session in Lift.

V.scala

package code

import java.util.{ResourceBundle, Locale}

import xml.{Node, NodeSeq}

import net.liftweb.util.Helpers.tryo
import net.liftweb.http.{Templates, LiftRules, S}
import net.liftweb.common._
import net.liftweb.util.{BundleBuilder, Helpers, NamedPF, Props}

object V extends Loggable {
  var resourceBundles: Map[Locale, List[ResourceBundle]] = Map()

  def ?(s: String, xs: Any*): String = tryo {
    S.?(s, xs: _*)
  } getOrElse ({
    logger.error("error while looking up '" + s + "': not in session")
    s
  })

  def ?(locale: Locale, str: String, xs: Any*): String = tryo {
    val trans = S.session match {
      case Full(sess) =>
        S.?(str, locale)
      case _ =>
        def rawResBundle(loc: Locale): Box[ResourceBundle] = {
          for {
            xml <- Templates("_resources" :: Nil, loc)
            bundle <- BundleBuilder.convert(xml, loc)
          } yield bundle
        }

        val bundle = if (resourceBundles.isDefinedAt(locale)) {
          // check if we have a bundle for the given locale
          resourceBundles(locale)
        } else {
          // otherwise, look it up
          val (lookupTime, bundles) = Helpers.calcTime({
            rawResBundle(locale).toList
          })
          logger.debug("[" + lookupTime + "ms] looked up bundles: " + bundles)
          resourceBundles += (locale -> bundles)
          bundles
        }
        // look up the given translation key
        val (translTime, trans) = Helpers.calcTime(bundle.flatMap(r => tryo(r.getObject(str) match {
          case s: String => Full(s)
          case n: Node => Full(n.text)
          case ns: NodeSeq => Full(ns.text)
          case _ => Empty
        }).flatMap(s => s)).find(s => true) getOrElse {
          LiftRules.localizationLookupFailureNotice.foreach(_(str, locale));
          str
        })
        logger.debug("[" + translTime + "ms] translated " + str + " into locale " + locale + ": '" + trans + "'")
        trans
    }
    val result = if (xs.length == 0)
      trans
    else
      String.format(locale, trans, xs.flatMap {case s: AnyRef => List(s) case _ => Nil}.toArray: _*)
    result
  } getOrElse ({
    logger.error("error while looking up '" + str + "': not in session")
    str
  })
}