Add Support for Constraint-based UserID in strategy

Problem to solve

Feature Flag users can define different strategies today, namely percent of users, userIDs and user lists. Adding constraints can add an additional layer of flexibility, as they can exclude specific users from the list for certain flags.

Further Details

A future version of Unleash plans on supporting a very flexible strategy involving constraint-based gates. If we can support this strategy when it releases, it would allow our own feature flag offering to handle a number of its current gaps.

One potential issue is that it would greatly impact our current feature flag UI.

Intended users

Anyone who uses feature flags.

Proposal

Constraints is part of a strategy - it is not stand-alone. For the MVC we will support a single constraint to be added to a strategy.

• The user will have the option to add/remove a constraint to/from a strategy. When none exists - Add constraint will be visible. When a constraint exists the delete button shall be visible.
• For the MVC we will only support the UserID constraint (@afontaine can we also support user list or is this additional effort?)
• The user shall be able to add user IDs that will be excluded from this strategy comma separated (reuse the current userID logic)
• Any user listed in this text box will not see the feature flag functionality

Mock Ups

Links / references

Unleash Constraint Flags