Affects Version/s: None
Fix Version/s: 1.6.0
The problem can easily be reproduce.
Once GenerateTableFetch store state and encounter NiFi instance reboot.
(Dynamic naming table by expression language)
The exception will occur.
The error in source code is list below.
if (type == null)
When this situation happened. The FlowFile will also be grab and can't release or observed.
Processor can't grab existing column type from columnTypeMap through instance reboot.
Hence will inevidible get this exception, rollback FlowFile and never success.
QueryDatabaseTable processor will not encounter this exception due to it setup(context) every time,
While GenerateTableFetch will not pass the condition and thus try to fetch column type from 0 length columnTypeMap.
if (!isDynamicTableName && !isDynamicMaxValues)
I can take the issue if it is recognize as bug.