[NIFI-6901] Version Control version change completes even when cancelled.

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 1.9.0
• Component/s: Core Framework
• Assignee: Unassigned
• Reporter: Matthew Clarke
• Created: 22/Nov/19 18:33
• Updated: 22/Nov/19 18:33

Description

The UI presents misleading/incorrect information when user cancels a version change on a version controlled Process group.

Simple test to reproduce.
Create a test Process group and build below flow inside it:
GenerateFlowFile ---> ExecuteStreamCommand --> UpdateAttribute

Configure the ExecuteStreamCommand processor with configured Command Path set to "sleep" and configured Command Argument of 300.

Version control this test PG.
edit the ExecuteStreamCommand configured Command Argument to 600.

Now commit version 2 of the test PG to version control.

Start the dataflow.

Now try to "change version" and select version 1.
UI will display "Stopping Affected Components" and then "Stopping Affected Processors".
It will not progress past this because the ExecuteStreamCommand still has an active thread. After 10 minutes when thread competes, version change will complete.
Now let us assume a thread that will never complete (hung) or a thread that may run for hours. We can click on the "cancel" button in the UI. NiFi displays that the version change operation has been cancelled.

Looking at the UI we see processor in a stopped state (cancel simply leaves you at state it was at in the version control process at the time user hit "cancel").

On top of that, it really did not cancel. If the user right clicks on ExecuteStreamCommand and selects "terminate", the version change finishes and starts the processor again.