Question

我正尝试使用Play的EssentialAction以下列方式将文件内容流式传输到S3：

  def upload(fileName: String) = EssentialAction { request =>
    val (iteratee, enumerator) = Concurrent.joined[Array[Byte]]
    blobStore.streamToStore(fileName, enumerator) //consumes the enumerator, streams to S3 and returns Future[Unit]
    iteratee.map { _ =>
      Logger.debug(s"Successfully uploaded file=$fileName")
      Created(Json.obj("id" -> fileName))
    }
  }

如果blobStore.streamToStore流成功，但如果流式传输时出现任何错误，则上述工作正常，但请求永远不会完成，在recover上执行iteratee也无济于事。在这种情况下，有人可以解释如何处理错误吗？

Answer 1

我必须在错误时完成使用枚举器：

blobStore.streamToStore(fileName, enumerator).recover {
  case throwable =>
    /* consume the enumerator for request to complete */
    enumerator |>> Iteratee.consume[Array[Byte]]().map(_ => throw throwable)
}
iteratee.map { _ =>
  Logger.debug(s"Successfully uploaded file=$fileName")
  Created(Json.obj("id" -> fileName))
}.recover {
  case NonFatal(throwable) => 
     InternalServerError(Results.EmptyContent())
}

Play Framework：将文件内容流式传输到S3

1 个答案: