Spark使用REST API获取stdout和stderr

Question

我使用Spark REST API执行Spark作业，如何获得每个Spark作业的stdout和stderr？

我阅读了文档Monitoring and Instrumentation。

application API运作良好，响应如下：

[ {
  "id" : "app-20190308150153-0039",
  "name" : "Spark shell",
  "attempts" : [ {
    "startTime" : "2019-03-08T15:01:52.759GMT",
    "endTime" : "1969-12-31T23:59:59.999GMT",
    "lastUpdated" : "2019-03-08T15:01:52.759GMT",
    "duration" : 0,
    "sparkUser" : "root",
    "completed" : false,
    "appSparkVersion" : "2.3.1",
    "lastUpdatedEpoch" : 1552057312759,
    "startTimeEpoch" : 1552057312759,
    "endTimeEpoch" : -1
  } ]
} ]

所以我尝试了/applications/[base-app-id]/logs这样的API：

wget localhost:4040/api/v1/applications/app-20190308150153-0039/logs

但是得到一个令人困惑的答复。响应是

PK

PK是什么？如何获得正确的答案？