[AMBARI-18057] NullPointerException When Retrieving Cluster via API Due To Database Inconsistency

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 2.0.0
• Fix Version/s: 2.4.0
• Component/s: ambari-upgrade
• Assignee: Jonathan Hurley
• Reporter: Jonathan Hurley
• Created: 07/Aug/16 20:06
• Updated: 08/Aug/16 05:42
• Resolved: 08/Aug/16 04:02

Description

Noticed the following on an upgraded cluster:
This is not related to EU it seems:

java.lang.NullPointerException
        at org.apache.ambari.server.controller.internal.AlertResourceProvider.toResource(AlertResourceProvider.java:277)
        at org.apache.ambari.server.controller.internal.AlertResourceProvider.getResources(AlertResourceProvider.java:234)
        at org.apache.ambari.server.controller.internal.AlertResourceProvider.queryForResources(AlertResourceProvider.java:160)
        at org.apache.ambari.server.controller.internal.ClusterControllerImpl$ExtendedResourceProviderWrapper.queryForResources(ClusterControllerImpl.java:966)
        at org.apache.ambari.server.controller.internal.ClusterControllerImpl.getResources(ClusterControllerImpl.java:141)
        at org.apache.ambari.server.api.query.QueryImpl.doQuery(QueryImpl.java:529)
        at org.apache.ambari.server.api.query.QueryImpl.queryForResources(QueryImpl.java:398)
        at org.apache.ambari.server.api.query.QueryImpl.execute(QueryImpl.java:222)

It looks like this is a problem with database consistency, namely that our upgrade logic does NOT properly enforce non-null and default values!

"Not good..."

      //TODO workaround for default values, possibly we will have full support later
      if (columnInfo.getDefaultValue() != null) {
        columnInfo.setNullable(true);
      }

Turns out we're doing at least 2 things very wrong here when changing the DB on Ambari upgrade:

• Not enforcing non-NULL constraint on columns
• Not enforcing a default constraint on column

This is most likely due to limitations in EclipseLink's TableDefinition and FieldDefinition classes which we rely on for our upgrade logic.

Issue Links

• links to: Reviewboard