NIFI-10019: SendTrapSNMP works without flowfile, upgraded to JUnit5

[Lehel44]

Summary

• SendTrapSNMP fix to work without flowfile as well
• Upgraded tests from JUnit4 to JUnit5

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[nandorsoma]

Hey @Lehel44!
Thank you for this contribution! I have tested the feature with ListenTrapSNMP receiving SendTrapSNMP's request. I have inline comments and I also found this bug during testing:

When I set Generic Trap Type to 1 and Specific Trap Type to 3 I get a validation exception, but after that a NullPointerException too. I think we shouldn't be able to start the processor and then we won't get the second exception.

java.lang.IllegalArgumentException: Invalid argument: Generic Trap Type is not [6 - Enterprise Specific] but Specific Trap Type is provided.
        at org.apache.nifi.snmp.configuration.V1TrapConfiguration$Builder.build(V1TrapConfiguration.java:112)
        at org.apache.nifi.snmp.processors.SendTrapSNMP.onTrigger(SendTrapSNMP.java:145)
…
2022-05-20 14:23:37,376 ERROR [Timer-Driven Process Thread-9] o.a.nifi.snmp.processors.SendTrapSNMP SendTrapSNMP[id=e14c1a22-0180-1000-8d49-668bf9378c73] Processing halted: yielding [1 sec]
java.lang.NullPointerException: null
        at org.apache.nifi.controller.repository.StandardProcessSession.getRecord(StandardProcessSession.java:800)
        at org.apache.nifi.controller.repository.StandardProcessSession.validateRecordState(StandardProcessSession.java:3701)
        at org.apache.nifi.controller.repository.StandardProcessSession.penalize(StandardProcessSession.java:2195)

Fully configured processor looked like this when I was testing:

If I understand correctly Specific Trap Type is only needed when Generic Trap Type is 6. Shouldn't we make that property depends on the other? Also would it make sense to select the values instead of using a text field?

Another things I've found during testing, but they are not part of the PR:

• If 0 value for port is invalid, then why it is the default value? Why don't we init it with null value or with a standard port if there is any for this protocol?
• ListenTrapSNMP ran almost a million times, while for example ListenTCP ran 556 times in the same interval.
• More interesting is that ListenTCP measured correctly the Time for the task, but ListenTrapSNMP not, while as I said both were running for about 5 secs. Please see the screenshots below:
  
  

[Lehel44]

@nandorsoma Thank you for the review! I will check the ListenTrapSNMP running times in #6034 as this PR deals only with SendTrapSNMP.
I think SpecificTrapType cannot depend on GenericTrapType value because Expression Language is supported with flowfile scope. Validation happens before we start the processor but when the values are being parsed from flowfile attributes runtime exception will be thrown.

[nandorsoma]

Hey @Lehel44!
Thank you for the additional changes. I have one question inline and also responded to you in one of our previous conversation.

[nandorsoma]

Oh, and an extra one: Shouldn't additional commits start with the ticket number?

[Lehel44]

No, it will be squashed in the end.

[tpalfy]

LGTM, thanks for your work @Lehel44!
Pushed to main.