NIFI-5871 ignore UUID attribute when copying flow file attributes

[SavtechSolutions]

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[patricker]

You can probably just copy the existing code from StandardProcessSession, then it will be consistent:

final Map<String, String> updatedAttributes;
if (attributes.containsKey(CoreAttributes.UUID.key())) {
        updatedAttributes = new HashMap<>(attributes);
        updatedAttributes.remove(CoreAttributes.UUID.key());
} else {
        updatedAttributes = attributes;
}

[MikeThomsen]

Only change I'd make here is putting that into the constructor. Other than that LGTM.

[SavtechSolutions]

@patricker I've incorporated your feedback

[MikeThomsen]

Approval still stands. Will wait to see what Travis does.

At least one processor's unit tests are expecting the same UUID to be present.

[MikeThomsen]

Running the build locally and got build errors that need to be address:

[ERROR] Tests run: 15, Failures: 4, Errors: 0, Skipped: 0, Time elapsed: 0.483 s <<< FAILURE! - in org.apache.nifi.processors.standard.TestWait
[ERROR] testReplaceAttributes(org.apache.nifi.processors.standard.TestWait)  Time elapsed: 0.077 s  <<< FAILURE!
org.junit.ComparisonFailure: expected:<[3d5b9e68-5960-4557-aadd-89f299b7f7c0]> but was:<[5db4833b-4406-405c-bbfe-3e271a2aeec5]>
	at org.apache.nifi.processors.standard.TestWait.testReplaceAttributes(TestWait.java:238)

[ERROR] testWaitForTotalCount(org.apache.nifi.processors.standard.TestWait)  Time elapsed: 0.006 s  <<< FAILURE!
org.junit.ComparisonFailure: expected:<[2bcf93d4-2bca-4377-b647-baa4d26e4e28]> but was:<[d467324b-1bf6-4a62-821d-3d1df7dfa3ba]>
	at org.apache.nifi.processors.standard.TestWait.testWaitForTotalCount(TestWait.java:363)

[ERROR] testWaitForSpecificCount(org.apache.nifi.processors.standard.TestWait)  Time elapsed: 0.006 s  <<< FAILURE!
org.junit.ComparisonFailure: expected:<8[8f03f6e-b58d-432b-95fd-3438e399f018]> but was:<8[22e1e1e-25f0-4db9-8a36-15a8d24b1532]>
	at org.apache.nifi.processors.standard.TestWait.testWaitForSpecificCount(TestWait.java:450)

[ERROR] testKeepOriginalAttributes(org.apache.nifi.processors.standard.TestWait)  Time elapsed: 0.001 s  <<< FAILURE!
org.junit.ComparisonFailure: expected:<[7836fb9a-a276-404d-9c13-d51984bc2f6b]> but was:<[bc5fbf7e-3945-4d79-9d21-e84b44adea57]>
	at org.apache.nifi.processors.standard.TestWait.testKeepOriginalAttributes(TestWait.java:282)

[SavtechSolutions]

Now this is strange - is there a remote chance that this behavior (copying UUID) is expected and it's not a bug? Or is this just an unit test with incorrect assumptions?

[patricker]

@SavtechSolutions Yes, this is a bug in the tests I think.
I can see they manually provide a custom UUID instead of letting NiFi generate it.

[SavtechSolutions]

@patricker Yes, I'm inclined to agree - the enqueue() call with attributes uses the same putAllAttributes call under the hood, so there's no way it should be able to retain the UUID attribute. I'll get to fix the tests, thanks.

[MikeThomsen]

AFAIK, there is no reason why uuid should be inherited by a flowfile even in a parent-child scenario since the child is a new flowfile branched off.

[patricker]

@MikeThomsen I think the test is showing that this isn't a parent/child scenario, but showing that it's the same FlowFile from start to finish.

If there were a way to inject content into MockFlowFile, then we could build one, pass that in to enqueue and the test would actually work.