Feature flags

[MichaelAkvo]

Certain features should be behind a flag.

Requirements

Fast to query

A feature might be checked multiple times in one request. The result shouldn't be a request for every check.

Permissions

Features should be able to be tied to users, groups (M&E manager, enumerator, etc.) , or organisations.

Feature targets

• Organisation
• Program
• Project

Prior Art

django-waffle

https://waffle.readthedocs.io/en/stable/types/flag.html

Has custom model. It allows overriding the flag activeness check

Can only use one model. Not sure about speed and caching. Doesn't handle hierarchies at all Has an admin

gargoyle

https://gargoyle-yplan.readthedocs.io/en/latest/usage.html

Allows handling hierarchies, but not of different models Complicated and meh documentation

Provides an admin

Allows creating your own conditions and specifying which switch uses which

django-flags

https://cfpb.github.io/django-flags/api/conditions/

Implementation Options

Feature definition in settings

The types of features can be declared in the settings. This would remove one query to find out which features have been defined in the first place. However, it would probably still require the features themselves to be saved in the DB, thus duplicating data :thinking: