NIFI-15880: Allow Connectors to enter a Troublehshooting mode where the flow beco…

[markap14]

…mes modifiable and user-managed (temporarily) rather than Connector managed.

Summary

NIFI-00000

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[rfellows]

The way this works currently is a bit confusing. You can enter troubleshooting mode while the processor is running, but you can't end troubleshooting with it still running. This forces the user to have to manually stop all processors before they would be allowed to end troubleshooting. For large connectors, this will be a tedious process of manually stopping everything.

It might be more palatable if STOP was a valid action on the connector as a whole while in troubleshooting mode. But it is explicitly not allowed in the current state.

[rfellows]

ConnectorRepository.getConnectors() got a required ConnectorSyncMode parameter. But FlowController is still calling getConnectors() with no args. Results in a compile error.