[NIFI-11342] HDFS processors fail to get ClassloaderIsolationKey at startup

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.0.0-M1, 1.22.0
• Assignee: Mark Bathori
• Reporter: Mark Bathori
• Created: 25/Mar/23 16:10
• Updated: 30/Jun/23 15:14
• Resolved: 05/Apr/23 15:45

Description

At the start of NiFi, the HDFS processors fail to get ClassloaderIsolationKey when only KerberosUserService is provided. The processor tries the get the isolation key by calling the createKerberosUser method on the service but it fails because at the time of method call the controller service is in Disabled state.

https://github.com/apache/nifi/blob/main/nifi-nar-bundles/nifi-extension-utils/nifi-hadoop-utils/src/main/java/org/apache/nifi/processors/hadoop/AbstractHadoopProcessor.java#L224

 Error message:

Failed to determine ClassLoader Isolation Key for PutHDFS[id=192e8080-0187-1000-ee4f-a7100d9d7dbb]. This could result in unexpected behavior by this processor.: org.apache.nifi.controller.service.ControllerServiceDisabledException: Cannot invoke method public abstract org.apache.nifi.security.krb.KerberosUser org.apache.nifi.kerberos.KerberosUserService.createKerberosUser() on Controller Service with identifier 0e84e32e-0187-1000-5e37-8cd7279916f6 because the Controller Service's State is currently DISABLED

The problem only occurs after NiFi restart. Adding a new HDFS processor to the canvas and setting the Kerberos UserService can properly get the isolation key.

Issue Links

• is duplicated by: NIFI-10412 [HDFS] Failed to determine ClassLoader Isolation Key for PutHDFS
• links to: GitHub Pull Request #7121