Add Flipper Discards Actors When Feature Fully Enabled as a Rails TIL

rails/flipper-discards-actors-when-feature-fully-enabled.md

@@ -0,0 +1,36 @@
+# Flipper Discards Actors When Feature Fully Enabled
+
+Let's say I have a Flipper feature flag that I have enabled for a handful of
+users. When I eventully go to globally enable that feature flag with the big
+green 'Enable' button, the gate short-circuit evalutes to true everywhere. This
+is what grants access to anyone when it is enabled.
+
+There is another thing that happens under the hood when the switch is flipped.
+All those individual actor records I created for that feature flag get wiped
+out.
+
+In the ideal case, that's not an issue because the flag is fully on going
+forward. But what about the scenario where I need to rollback the feature
+release.
+
+What if I'm thinking, "whoops, my team isn't ready to handle the influx of users
+for this feature, I want to go back to having it partially enabled for that
+small list of users for now."
+
+I'll be out of luck because that list of _actors_ was cleared. So if I'm
+anticipating that I might want to be able to rollback in that way, I should
+capture a snapshot of the set of actors I had enabled for that feature.
+
+```ruby
+actors = Flipper[:some_feature].actors_value.to_a
+puts JSON.pretty_generate(actors)
+```
+
+I could then iterate through that list making calls to individually enable it
+for each actor:
+
+```ruby
+Flipper.enable_actor(:some_feature, Flipper::Actor.new(flipper_id))
+```
+
+I give a full example of what that script could look like in [Rollback a Flipper Feature Flag Release](https://www.visualmode.dev/rollback-a-flipper-feature-flag-release).