NIFI-6112: Add some useful commands to NiFi Toolkit for automating NiFi cluster construction.

[yoshiata]

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[alopresto]

Wow, this looks like a very helpful feature for people setting up their NiFi instances. I haven't gotten a chance to do a full review yet, but some quick notes:

• For anyone else doing a review, there is extensive documentation and examples in the Jira - NIFI-6112
• In the examples, the command to add a user to a group specifies the UUID of the user, rather than the identity (aka user1). Is there also a capability to do it by identity (i.e. % ./cli.sh nifi create-user-group --userGroupName admin --userList user1)?

[bbende]

This looks really cool, thanks for contributing!

I will definitely try to review this soon, unless Andy or someone else gets to it first.

[yoshiata]

@alopresto

Is there also a capability to do it by identity (i.e. % ./cli.sh nifi create-user-group --userGroupName admin --userList user1)?

There is no such capability. I will add it.

[yoshiata]

@alopresto
Since UUID is difficult to use, I will fix not to use UUID to specify users and user groups. (use only the identity.) Is that okay?
(However, since the controller service may have duplicate names, specify it by UUID.)

[alopresto]

I think there is definitely value to being able to specify the UUID as it is unique and clearly identifies the user objects. I just like the ability to use either value. Is it ok to support both?

[yoshiata]

I understood. I will fix to support both.

[yoshiata]

I fixed to support both UUID and identity for user / user group specification.
16905fc

I also added documentation and examples.
https://issues.apache.org/jira/browse/NIFI-6112?focusedCommentId=16793259&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-16793259

[bbende]

Tested all of the commands, and overall this is awesome!

Left some comments of a few things that should be considered before we merge this in. Thanks!

[yoshiata]

@bbende
Thank you for reviewing the last commit.
I updated the PR based on your reviews. Please review.

[bbende]

Changes look good! Thanks for addressing the feedback and for contributing all of this, going to merge

[yoshiata]

Thank you for reviewing and merging it!