Scala Play 2.2应用程序中的CORS过滤器

package filters

import play.api.mvc._
import play.api.libs.concurrent.Execution.Implicits.defaultContext
import play.api.GlobalSettings

class CorsFilter extends EssentialFilter {
  def apply(next: EssentialAction) = new EssentialAction {
    def apply(requestHeader: RequestHeader) = {
      next(requestHeader).map { result =>
        result.withHeaders("Access-Control-Allow-Origin" -> "*","Access-Control-Expose-Headers" -> "WWW-Authenticate,Server-Authorization","Access-Control-Allow-Methods" -> "POST,GET,OPTIONS,PUT,DELETE","Access-Control-Allow-Headers" -> "x-requested-with,content-type,Cache-Control,Pragma,Date")
      }
    }
  }
}

object Global extends WithFilters(new CorsFilter) with GlobalSettings

以及预检选项操作：

def preflight(all: String) = Action {
    Ok("").withHeaders("Access-Control-Allow-Origin" -> "*","Allow" -> "*",DELETE,OPTIONS","Access-Control-Allow-Headers" -> "Origin,X-Requested-With,Content-Type,Accept,Referrer,User-Agent");
  }

定义了一条路线：

OPTIONS        /*all                                controllers.Application.preflight(all: String)

似乎正在发生的是CorsFilter代码没有被执行.我打开了调试器,但没有看到我的任何请求到达此过滤器.为什么会这样？是否有其他地方我需要定义过滤器的东西,以便Play可以看到它？