播放 2.5 迁移错误:使用正文解析器的自定义操作:找不到参数 mat:akka.stream.Materializer

Question

我有一个 Play 框架应用程序，版本 2.4 迁移到 2.5，一切都完成了！但在我使用 BodyParser的自定义操作中抛出错误，

 def isAuthenticatedAsync[A](parser: BodyParser[A])(f: => Long => Request[A] => Future[Result]) = {
Security.Authenticated(userId, onUnauthorized) { user =>
  Action.async(parser)(request => f(user)(request))
}

}

使用这个：

def upload = isAuthenticatedAsync(parse.maxLength(5 * 1024 * 1024, parse.multipartFormData)) { userId => request =>
//Logger.info(s"")
request.body match {
  case Left(MaxSizeExceeded(length)) => Future(BadRequest(Json.toJson(ResultTemp("Your file is too large, we accept just " + length + " bytes!"))))
  case Right(multipartForm) =>

抛出错误：

could not find implicit value for parameter mat: akka.stream.Materializer

[error] def upload = Action.async（parse.maxLength（5 * 1024 * 1024， parse.multipartFormData）） { request =>

Answer 1

看起来您需要在控制器中注入物化器

class MyController @Inject() (implicit val mat: Materializer) {}