[YARN-8129] Improve error message for invalid value in fields attribute

• Type: Sub-task
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 2.10.0, 3.2.0, 3.0.4, 3.1.2
• Component/s: ATSv2
• Hadoop Flags: Reviewed
• Assignee: Abhishek Modi
• Reporter: Charan Hebri
• Created: 09/Apr/18 09:06
• Updated: 21/Aug/18 09:04
• Resolved: 21/Aug/18 09:04

Description

Query with invalid values for the 'fields' attributes throws a message that isn't very informative.
Reader log,

2018-04-09 08:59:46,069 INFO  reader.TimelineReaderWebServices (TimelineReaderWebServices.java:getEntities(595)) - Received URL /ws/v2/timeline/users/hrt_qa/flows/test_flow/apps?limit=3&fields=INFOS from user hrt_qa

2018-04-09 08:59:46,070 INFO  reader.TimelineReaderWebServices (TimelineReaderWebServices.java:handleException(173)) - Processed URL /ws/v2/timeline/users/hrt_qa/flows/test_flow/apps?limit=3&fields=INFOS but encountered exception (Took 1 ms.)

Here INFOS is the invalid value for the fields attribute.
Response,

{
  "exception": "BadRequestException",
  "message": "java.lang.Exception: No enum constant org.apache.hadoop.yarn.server.timelineservice.storage.TimelineReader.Field.INFOS",
  "javaClassName": "org.apache.hadoop.yarn.webapp.BadRequestException"
}

The message shouldn't ideally contain the enum information.