[NIFI-2432] Clarify message provided when local flow differs from cluster flow

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.0.0
• Component/s: Core Framework
• Assignee: Mark Payne
• Reporter: Mark Payne
• Created: 29/Jul/16 15:13
• Updated: 12/Jun/18 17:57

Description

Currently, when a node attempts to join a cluster, if its flow is different than the cluster flow, the message provided is not ideal. For example:

Local Fingerprint:   api.dto.ProcessorDTOPutFileWARN0 secTIMER_DRIVEN1 sec130 secnullConflict Resolution Strategy=replaceCreate Missing Directories=trueDirectory=/home/filePermissions=666NO
Cluster Fingerprint: api.dto.ProcessorDTOPutFileWARN0 secTIMER_DRIVEN1 sec130 secnullConflict Resolution Strategy=replaceDirectory=/home/filePermissions=666NO_AUTO_TERMINATED_RELATIONSHIPS6

From this, one can glean the difference between the flow if they understand the structure of the message, but it is not at all intuitive. At the point when this message is generated, we have both the proposed flow and the current flow. We also have methods that will convert both flows into DTO objects. So we should instead perform a more intelligent 'diff' and output message such as:

Proposed flow does not contain Process Group ABC(id=1234)

Proposed flow has different property values for Processor MyPutFile(id=4321):
Create Missing Directories = true (Local Flow)
Create Missing Directories = <NO VALUE SET> (Cluster Flow)

This makes it much more clear what the difference is between the flows so that the admin is able to determine how to address the issue.

Issue Links

• is related to: NIFI-1204 Improve cluster logging message when mismatch prevents Node from joining.