NIFI-6803 - ActionHandler Controller Services

[YolandaMDavis]

NIFI-6803 - updated to description

NIFI-6803 - add Spring reference to Notice

This PR provide default Action Handlers for Rules as Controller Services. Action Handlers included are:

LogHandler - Executes Logging Actions
ExpressionHandler - Execute MVEL or SpEL Expressions
RecordSinkHandler - Executes Actions that require Records to be Sent via Record Sink
ActionHandlerLookup - Provides a dynamic method for tying Action types to an Action Handler (e.g. a 'LOG' action type can align with the LogHandler service, 'SEND' to RecordSinkHandler, etc)

Attached is an example or how things can be invoked with an InvokedScriptedProcessor with the ActionHandlerLookup service used to invoke other handlers, however this test should also allow use of the individual handlers (and report when handlers can not support the provided action).

rules-test.zip

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[mattyb149]

Reviewing...

[mattyb149]

+1 LGTM, ran contrib-check and tried some sample flows with various action handler configurations. Thanks for this addition! Merging to master