security.scala

trait Security {
  /**
   * Retrieve the connected user email.
   */
  private def username(request: RequestHeader) = 
    request.session.get("username")

  /**
   * Redirect to login if the user in not authorized.
   */
  private def onUnauthorized(request: RequestHeader) =
   Results.Redirect(routes.Application.login())

  /**
   * Action for authenticated users.
   */
  def ifAuthenticated(f: String => Request[AnyContent] => Result) = 
    Action { req =>
      username(req).map(f(_)(req)) getOrElse(onUnauthorized(req))
    }

}