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Diffstat (limited to 'doc/development/feature_flags/controls.md')
| -rw-r--r-- | doc/development/feature_flags/controls.md | 63 |
1 files changed, 55 insertions, 8 deletions
diff --git a/doc/development/feature_flags/controls.md b/doc/development/feature_flags/controls.md index 309aecd7978..d4d1ec74591 100644 --- a/doc/development/feature_flags/controls.md +++ b/doc/development/feature_flags/controls.md @@ -96,7 +96,7 @@ As a guideline: Before toggling any feature flag, check that there are no ongoing significant incidents on GitLab.com. You can do this by checking the `#production` and `#incident-management` Slack channels, or looking for -[open incident issues](https://gitlab.com/gitlab-com/gl-infra/production/issues/?scope=all&utf8=%E2%9C%93&state=opened&label_name[]=incident) +[open incident issues](https://gitlab.com/gitlab-com/gl-infra/production/-/issues/?scope=all&utf8=%E2%9C%93&state=opened&label_name[]=incident) (although check the dates and times). We do not want to introduce changes during an incident, as it can make @@ -113,17 +113,58 @@ When you begin to enable the feature, please link to the relevant Feature Flag Rollout Issue within a Slack thread of the first `/chatops` command you make so people can understand the change if they need to. -To enable a feature for 25% of all users, run the following in Slack: +To enable a feature for 25% of the time, run the following in Slack: ```shell /chatops run feature set new_navigation_bar 25 ``` +This sets a feature flag to `true` based on the following formula: + +```ruby +feature_flag_state = rand < (25 / 100.0) +``` + This will enable the feature for GitLab.com, with `new_navigation_bar` being the name of the feature. This command does *not* enable the feature for 25% of the total users. Instead, when the feature is checked with `enabled?`, it will return `true` 25% of the time. +To enable a feature for 25% of actors such as users, projects, or groups, +run the following in Slack: + +```shell +/chatops run feature set some_feature 25 --actors +``` + +This sets a feature flag to `true` based on the following formula: + +```ruby +feature_flag_state = Zlib.crc32("some_feature<Actor>:#{actor.id}") % (100 * 1_000) < 25 * 1_000] +# where <Actor>: is a `User`, `Group`, `Project` and actor is an instance +``` + +During development, based on the nature of the feature, an actor choice +should be made. + +For user focused features: + +```ruby +Feature.enabled?(:feature_cool_avatars, current_user) +``` + +For group or namespace level features: + +```ruby +Feature.enabled?(:feature_cooler_groups, group) +``` + +For project level features: + +```ruby +Feature.enabled?(:feature_ice_cold_projects, project) +``` + If you are not certain what percentages to use, simply use the following steps: 1. 25% @@ -158,15 +199,21 @@ you run these 2 commands: ```shell /chatops run feature set --project=gitlab-org/gitlab some_feature true -/chatops run feature set some_feature 25 +/chatops run feature set some_feature 25 --actors +``` + +Then `some_feature` will be enabled for both 25% of actors and always when interacting with +`gitlab-org/gitlab`. This is a good idea if the feature flag development makes use of group +actors. + +```ruby +Feature.enabled?(:some_feature, group) ``` -Then `some_feature` will be enabled for both 25% of users and all users interacting with -`gitlab-org/gitlab`. +NOTE: -NOTE: **Note:** **Percentage of time** rollout is not a good idea if what you want is to make sure a feature -is always on or off to the users. +is always on or off to the users. In that case, **Percentage of actors** rollout is a better method. ### Feature flag change logging @@ -174,7 +221,7 @@ Any feature flag change that affects GitLab.com (production) will automatically be logged in an issue. The issue is created in the -[gl-infra/feature-flag-log](https://gitlab.com/gitlab-com/gl-infra/feature-flag-log/issues?scope=all&utf8=%E2%9C%93&state=closed) +[gl-infra/feature-flag-log](https://gitlab.com/gitlab-com/gl-infra/feature-flag-log/-/issues?scope=all&utf8=%E2%9C%93&state=closed) project, and it will at minimum log the Slack handle of person enabling a feature flag, the time, and the name of the flag being changed. |