Play Framework:如何为每个响应添加标题

Question

在下面Controller,Authenticated从请求标头中提取标记,并且当且仅当标记有效时才调用给定的操作(为简单起见,代码已经简化):

object MyController extends Controller {

  def Authenticated(action: Token => EssentialAction) = EssentialAction { requestHeader =>
    val jwt = requestHeader.headers.get(HeaderNames.AUTHORIZATION) match {
      case Some(header) => s"""$AuthScheme (.*)""".r.unapplySeq(header).map(_.head.trim)
      case _ => requestHeader.getQueryString("auth").map(UriEncoding.decodePath(_, SC.US_ASCII.name))
    }

    jwt match {
      case Some(t) if t.isValid =>
        val token: Token = authService.token(t)
        action(token)(requestHeader)
      case _ => Done(Unauthorized.withHeaders(HeaderNames.WWW_AUTHENTICATE -> AuthScheme))
    }
  }

  def getUser(userId: String) = Authenticated { token =>
    Action.async { request =>
      userService.find(userId).map {
        case Some(user) => Ok(Json.obj("user" -> user.asJson)).withHeaders(
            "token" -> authService.renew(token).asJson.toString
          )
        case _ => NotFound
      }
    }
  }
}

返回的令牌authService.token(t)是JWT(JSON Web令牌),它只能使用一次......所以我需要在每次请求后返回一个新令牌.想法是将新令牌放在响应头中.也就是说,有没有办法将token标头添加到每个响应,而无需withHeader在每个操作中调用？

Answer 1

您只需创建一个Filter,然后在Global.scala中添加WithFilters类.

import play.api.mvc._

object Global extends WithFilters(TokenFilter) {
  ...
}

这是一个用于记录的Filter示例,因此您可以轻松地更改它以满足您的需求.

val loggingFilter = Filter { (next, rh) =>
  val start = System.currentTimeMillis

  def logTime(result: PlainResult): Result = {
    val time = System.currentTimeMillis - start
    Logger.info(s"${rh.method} ${rh.uri} took ${time}ms and returned ${result.header.status}")
    result.withHeaders("Request-Time" -> time.toString)
  }

  next(rh) match {
    case plain: PlainResult => logTime(plain)
    case async: AsyncResult => async.transform(logTime)
  }
}