Simply Lift

17.2 Solution

If you’ve got a:

object MyService extends RestHelper {
....
}

And:

val ensureSession: PartialFunction[Req, Unit] = {
  case _ if isLoggedIn => 
}

then in Boot:

import net.liftweb.util.Helpers._

LiftRules.dispatch.append(ensureSession guard MyService)

This is a simple way to compose PartialFunctions and put a guard around all the elements of a PartialFunction.