NIFI-2923 Add expression language support to Kerberos parameters used…

[mauriziocolleluori]

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… by processors

[bbende]

Thank you for contributing. In addition to adding the expressionLanguageSupported flag on the property descriptors, we would also need to go through the code and find every place where the properties are evaluated, for example:

https://github.com/apache/nifi/blob/master/nifi-nar-bundles/nifi-hadoop-bundle/nifi-hdfs-processors/src/main/java/org/apache/nifi/processors/hadoop/AbstractHadoopProcessor.java#L283

And that would need to call evaluateAttributeExpressions().

[mauriziocolleluori]

Thank you for your feedback, I will add the necessary call to evaluateAttributeExpressions().

[pvillard31]

Hi @mauriziocolleluori,

If you still encounter issues in UI when testing properties while using expression language, please check that nifi.kerberos.krb5.file is correctly set in your nifi.properties file (and reference a readable file).

In addition, it would be great to do the same kind of modification in Kafka processors where Kerberos principal is also a property. Let me know if you are OK to do it, otherwise, I'll do it. Thanks!

[trixpan]

@mauriziocolleluori thank you for the contribution.

any intent on addressing @pvillard31 's comment? While a positive answer is more than welcome, a negative answer is also welcome... all we need to know is if this is ready to review or if you still plan to address the comments.

Cheers!

[mauriziocolleluori]

@trixpan @pvillard31 thank you for you comments. I will look into the Kafka processors and revert back once it's done.

[trixpan]

PR is looking good but that new tests were added to the affected processors
Would that be possible?

Cheers

[jtstorck]

@mauriziocolleluori Hello, and thank you for your contribution! I am working on a JIRA (https://issues.apache.org/jira/browse/NIFI-4010) that builds upon the changes in your PR. Could you please address the remaining comments to help get your PR committed?

[jtstorck]

@mauriziocolleluori I've cherry-picked your commits into my branch, and will be submitting a PR that includes your commits along with mine (for NIFI-4010). Thank you for your contribution to Apache NiFi!

When my PR is merged to master, your PR will be closed along with mine.