[AMBARI-17758] LogSearch Integration NullPointerException when LogSearch connection not available

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 2.4.0
• Fix Version/s: 2.4.0
• Component/s: ambari-server
• Assignee: Bob Nettleton
• Reporter: Bob Nettleton
• Created: 16/Jul/16 18:14
• Updated: 17/Jul/16 02:49
• Resolved: 17/Jul/16 01:06

Description

The following NullPointerException can occur intermittently in the LogSearch integration code in the Ambari REST layer:

java.lang.NullPointerException
	at org.apache.ambari.server.controller.logging.LogSearchDataRetrievalService.getLogFileTailURI(LogSearchDataRetrievalService.java:159)
	at org.apache.ambari.server.controller.logging.LoggingSearchPropertyProvider.populateResources(LoggingSearchPropertyProvider.java:92)
	at org.apache.ambari.server.controller.internal.ClusterControllerImpl.populateResources(ClusterControllerImpl.java:155)
	at org.apache.ambari.server.api.query.QueryImpl.queryForSubResources(QueryImpl.java:500)
	at org.apache.ambari.server.api.query.QueryImpl.queryForSubResources(QueryImpl.java:503)
	at org.apache.ambari.server.api.query.QueryImpl.queryForResources(QueryImpl.java:454)
	at org.apache.ambari.server.api.query.QueryImpl.execute(QueryImpl.java:222)
	at org.apache.ambari.server.api.handlers.ReadHandler.handleRequest(ReadHandler.java:77)
	at org.apache.ambari.server.api.services.BaseRequest.process(BaseRequest.java:145)
	at org.apache.ambari.server.api.services.BaseService.handleRequest(BaseService.java:126)
	at org.apache.ambari.server.api.services.BaseService.handleRequest(BaseService.java:90)
	at org.apache.ambari.server.api.services.ClusterService.getCluster(ClusterService.java:91)
	at sun.reflect.GeneratedMethodAccessor255.invoke(Unknown Source)

While the code that calls the LogSearchDataRetrievalService already has a check to determine if the LoggingRequestHelper is available (non-null), there is a change that a service might be stopped or crashes unexpected in between the initial check and this call.

This is usually an intermittent exception.

The LogSearchDataRetrievalService should be updated to include a check for null when attempting to access the LoggingRequestHelper implementation.

I'm working on a fix for this, and will be submitting a patch shortly.

Issue Links

• links to: ReviewBoard