NIFI-4250 - Elasticsearch 5 delete processor

[mans2singh]

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[mans2singh]

Hey Folks:

The travis-ci build is failing (? timing out) with the error included below. Can someone let me know how to resolve this ?

Thanks

org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionLexer.g
Output file /home/travis/build/apache/nifi/nifi-commons/nifi-expression-language/target/generated-sources/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionParser.java does not exist: must build /home/travis/build/apache/nifi/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionParser.g
org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionParser.g


No output has been received in the last 10m0s, this potentially indicates a stalled build or something wrong with the build itself.
Check the details on how to adjust your build configuration on: https://docs.travis-ci.com/user/common-build-problems/#Build-times-out-because-no-output-was-received

The build has been terminated

[mans2singh]

Hey Folks:

Let me know if you have any feedback/recommends for this processor.

Thanks

Mans

[mattyb149]

Don't worry about the ANTLR stuff, that seems to trip up Travis sometimes. I can review this either this weekend or early next week. One quick question is whether you think it would be too confusing for the user to just add "delete" as an operation to PutElasticsearch(5), it would require doc updates and such. I'm just thinking that after one version of a Delete ES processor is available, the rest would be desired, requested, and possibly implemented. If that were the case, would it be better to have 3 new processors for delete, or to update the 3 Put processors to accept delete? I'm not leaning one way or the other, I'm interested in your thoughts and others' in order to provide the best user experience.

[mans2singh]

@mattyb149

Regarding having a separate delete processor - I prefer single responsibility principle since it avoids confusion and mixing up configuration, processing logic, error handling, testing, maintenance etc. Along the same lines ElasticSearch provides separate JAVA delete/put/get request builders. Besides, overloading put and delete is confusing to me from the REST semantics.

Let me know your thoughts.

[mattyb149]

Makes sense to me, plus once the Extension Registry is in place, that might be the right spot for additional delete ES processors etc. I will review this for inclusion, thanks in advance!

[mans2singh]

@mattyb149 - Please let me know if you have any comments/recommendations on this processor. Thanks.

[mattyb149]

+1 LGTM, ran the build and tests, and tried a flow with various conditions (success, not found, failure), everything works well. Thanks for the contribution! Merging to master

[mans2singh]

Thanks @mattyb149