Description:

This contains the following:

• Feature flag plugin for core
• Single implementation of feature flag storage which is in the configuration file
• A manager that supports multiple storage methods for features and can be expanded on later
• An example feature called 'Example'
• Showing an optional HTML comment in the markup of the home of Matomo is the flag is enabled
• Added migration and bumped to new version 5.1.0-b5 so the plugin can be activated
• Console command to enable/disable/delete feature flag

To Test:

Add the following to your config:

[FeatureFlags]
Example_feature = "enabled"

Then go to the main dashboard, look at the source code and look for the content:

<!-- Feature flag example enabled -->

Then play around with the value, of the config:
disabled / remove it completely.

In the console you can enable/disable/delete using the following:

./console featureflags:enable Example
./console featureflags:disable Example
./console featureflags:delete Example

You can try this if you want, by adding a new feature flag class to another plugin that implements the FeatureFlagInterface.

Then test if you can enable that feature flag as well.

Once the featureflag plugin is installed/activated, the DI will be available and can be used by just injecting FeatureFlagManager into the constructor of a class that needs it.

Review

• Functional review done
• Potential edge cases thought about (behavior of the code with strange input, with strange internal state or possible interactions with other Matomo subsystems)
• Usability review done (is anything maybe unclear or think about anything that would cause people to reach out to support)
• Security review done
• Wording review done
• Code review done
• Tests were added if useful/possible
• Reviewed for breaking changes
• Developer changelog updated if needed
• Documentation added if needed
• Existing documentation updated if needed