[YARN-9857] TestDelegationTokenRenewer throws NPE but tests pass

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 3.3.0
• Assignee: Ahmed Hussein
• Reporter: Ahmed Hussein
• Created: 25/Sep/19 19:32
• Updated: 26/Sep/19 16:30
• Resolved: 26/Sep/19 16:17

Description

TestDelegationTokenRenewer throws some NPEs:

2019-09-25 12:51:23,446 WARN  [pool-19-thread-2] security.DelegationTokenRenewer (DelegationTokenRenewer.java:handleDTRenewerAppSubmitEvent(945)) - Unable to add the application to the delegation token renewer.
java.lang.NullPointerException
	at org.apache.hadoop.yarn.server.resourcemanager.security.DelegationTokenRenewer$DelegationTokenRenewerRunnable.handleDTRenewerAppSubmitEvent(DelegationTokenRenewer.java:942)
	at org.apache.hadoop.yarn.server.resourcemanager.security.DelegationTokenRenewer$DelegationTokenRenewerRunnable.run(DelegationTokenRenewer.java:918)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
2019-09-25 12:51:23,446 DEBUG [main] util.MBeans (MBeans.java:unregister(138)) - Unregistering Hadoop:service=ResourceManager,name=CapacitySchedulerMetrics
Exception in thread "pool-19-thread-2" java.lang.NullPointerException
	at org.apache.hadoop.yarn.server.resourcemanager.security.DelegationTokenRenewer$DelegationTokenRenewerRunnable.handleDTRenewerAppSubmitEvent(DelegationTokenRenewer.java:951)
	at org.apache.hadoop.yarn.server.resourcemanager.security.DelegationTokenRenewer$DelegationTokenRenewerRunnable.run(DelegationTokenRenewer.java:918)
2019-09-25 12:51:23,447 DEBUG [main] util.MBeans (MBeans.java:unregister(138)) - Unregistering Hadoop:service=ResourceManager,name=MetricsSystem,sub=Stats
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
2019-09-25 12:51:23,447 INFO  [main] impl.MetricsSystemImpl (MetricsSystemImpl.java:stop(216)) - ResourceManager metrics system stopped.

the RMContext dispatcher is not set for the RMMock which results in NPE accessing the event handler of the dispatcher inside DelegationTokenRenewer.