play for scala 实现SessionFilter 过滤未登录用户跳转到登录页面

package filters
import javax.inject.{Inject, Singleton}
import akka.stream.Materializer
import controllers.routes
import play.api.mvc.{Filter, RequestHeader, Result, Results}
import scala.concurrent.Future
@Singleton
class SessionFilter @Inject()(implicit val mat: Materializer) extends Filter {
 def apply(nextFilter: RequestHeader => Future[Result])
      (requestHeader: RequestHeader): Future[Result] = {
  if (!requestHeader.session.get("user").isDefined && !requestHeader.path.contains("/signin") && !requestHeader.path.contains("/assets/")) {
   Future.successful(Results.Redirect(routes.SignController.showSignin()))
  } else {
   nextFilter(requestHeader)
  }
 }
}

import javax.inject._
import filters.{ExampleFilter, SessionFilter}
import play.api._
import play.api.http.HttpFilters
import play.api.mvc._
/**
 * This class configures filters that run on every request. This
 * class is queried by Play to get a list of filters.
 *
 * Play will automatically use filters from any class called
 * `Filters` that is placed the root package. You can load filters
 * from a different class by adding a `play.http.filters` setting to
 * the `application.conf` configuration file.
 *
 * @param env Basic environment settings for the current application.
 * @param exampleFilter A demonstration filter that adds a header to
 * each response.
 */
@Singleton
class Filters @Inject() (
 env: Environment,
 exampleFilter: ExampleFilter, sessionFilter: SessionFilter) extends HttpFilters {
 override val filters = {
  // Use the example filter if we're running development mode. If
  // we're running in production or test mode then don't use any
  // filters at all.
  if (env.mode == Mode.Dev) Seq(exampleFilter) else Seq.empty
  Seq(sessionFilter)
 }
}