NIFI-10114 Remove Single Refresh from ShellUserGroupProvider

[exceptionfactory]

Summary

NIFI-10114 Removes refresh methods for a single user or group from the ShellUserGroupProvider in NiFi and NiFi Registry.

The single user refresh is not necessary since the information is available from the initial enumeration of known users. The single group refresh does not perform as expected because the UserGroupProvider.getGroup() method receives a UUID identifier specific to NiFi. The group UUID is not sufficient to perform a single group lookup using available commands.

Tracking

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• Apache NiFi Jira issue created

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• Pull Request title starts with Apache NiFi Jira issue number, such as NIFI-00000
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Build

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  • JDK 8
  • JDK 11
  • JDK 17

Licensing

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[kevdoran]

Always nice to remove unneeded code! Thanks for this contribution @exceptionfactory. +1 based on the PR diff, but will wait for the CI builds to complete before merging.

[thenatog]

Reviewed and tested this also, looks good to me.

+1

[praneethkumarpidugu]

Just curious to know, what penetration testing tools are used for identifying security vulnerabilities in Apache NiFi ?

[joewitt]

@praneethkumarpidugu It is better to send this via an email to users@nifi.apache.org as this PR is closed/completed.

To answer your question the Apache NiFi community itself offers no guarantees of any specific penetration testing or static security scanning tools in general. For such guarantees you likely should seek out vendor assistance and options exist. This community for Apache NiFi has some dependency scans built into the build process, does receive the benefit of reports from users and vendors, and responds promptly. A good place to start to understand our security posture generally is https://nifi.apache.org/security.html