[SPARK-20354][CORE][REST-API]When I request access to the 'http: //ip:port/api/v1/applications' link, return 'sparkUser' is empty in REST API.

[guoxiaolongzte]

What changes were proposed in this pull request?

When I request access to the 'http: //ip:port/api/v1/applications' link, get the json. I need the 'sparkUser' field specific value, because my Spark big data management platform needs to filter through this field which user submits the application to facilitate my administration and query, but the current return of the json string is empty, causing me this Function can not be achieved, that is, I do not know who the specific application is submitted by this REST Api.

current return json:
[ {
"id" : "app-20170417152053-0000",
"name" : "KafkaWordCount",
"attempts" : [ {
"startTime" : "2017-04-17T07:20:51.395GMT",
"endTime" : "1969-12-31T23:59:59.999GMT",
"lastUpdated" : "2017-04-17T07:20:51.395GMT",
"duration" : 0,
"sparkUser" : "",
"completed" : false,
"endTimeEpoch" : -1,
"startTimeEpoch" : 1492413651395,
"lastUpdatedEpoch" : 1492413651395
} ]
} ]

When I fix this question, return json:
[ {
"id" : "app-20170417154201-0000",
"name" : "KafkaWordCount",
"attempts" : [ {
"startTime" : "2017-04-17T07:41:57.335GMT",
"endTime" : "1969-12-31T23:59:59.999GMT",
"lastUpdated" : "2017-04-17T07:41:57.335GMT",
"duration" : 0,
"sparkUser" : "mr",
"completed" : false,
"startTimeEpoch" : 1492414917335,
"endTimeEpoch" : -1,
"lastUpdatedEpoch" : 1492414917335
} ]
} ]

How was this patch tested?

manual tests

Please review http://spark.apache.org/contributing.html before opening a pull request.

[srowen]

@squito do you have an opinion?

[squito]

yeah, looks like the right change, I think it was just overlooked in https://issues.apache.org/jira/browse/SPARK-14245

I'd ask that you add an assertion to this unit test: https://github.com/apache/spark/blob/master/core/src/test/scala/org/apache/spark/ui/UISeleniumSuite.scala#L655

(attempts(0) \ "sparkUser").extract[String] should not be ("")

aside, I'm not sure why SPARK-14245 introduced a different way of getting the user from what the history server uses, but in any case I think this change is right, to do the same thing as the UI, even if those internals should be changed.

[ajbozarth]

Thanks for catching this, somehow I totally missed it last year in my original PR. I don't think I was working on the API side as much then.

[vanzin]

ok to test

[SparkQA]

Test build #75870 has finished for PR 17656 at commit 9ecc1a0.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[vanzin]

Merging to master / 2.2.