[CASSANDRA-17544] Add EnableFlag to guardrails API

• Type: Improvement
• Status: Resolved
• Priority: Low
• Resolution: Fixed
• Fix Version/s: 5.0-alpha1, 5.0
• Component/s: Feature/Guardrails
• Change Category: Code Clarity
• Complexity: Low Hanging Fruit
• Platform: All

Source Control Link

https://github.com/apache/cassandra/commit/013acc641c5d487b07be5c082af1e85d26bd127f

Test and Documentation Plan

PR
trunk

• Assignee: Bernardo Botella Corbi
• Reporter: Josh McKenzie

Authors

Bernardo Botella Corbi

Reviewers

Andres de la Peña, Josh McKenzie, Yifan Cai

• Created: 11/Apr/22 18:05
• Updated: 12/Sep/23 13:02
• Resolved: 06/May/22 20:11

Description

Currently we only have a DisableFlag which, for guardrails where we're enabling or disabling a feature, leads to some pretty odd ergonomics in the code. For example:

 

public static final DisableFlag compactTablesEnabled =
new DisableFlag("compact_tables",
                state -> !CONFIG_PROVIDER.getOrCreate(state).getCompactTablesEnabled(),
                "Creation of new COMPACT STORAGE tables"); 

So far, the usage of these toggle flags appears to be skewed heavily towards the inverse, or an EnableFlag that'd look something like this:

public static final EnableFlag featureEnabled = new EnableFlag("feature_name", state -> CONFIG_PROVIDER.getOrCreate(state).getCompactTablesEnabled(), "Text for feature"); 

While it's a relatively small change it'll help tidy up some of the guardrails framework and make the logic clearer.