💯 Percentage rollout

Overview

A percentage rollout refers to a gradual release of a new feature to a subset of users. Instead of making the feature available to everyone at once, you want to have only a subset of your customers to see the new feature.

Define a percentage rollout

In GO Feature Flag, you can define a percentage rollout by setting the percentage of users that will see the new feature. You can define the percentage in the flag configuration, and it works for the default rule or any other targeting rule you define.

The expected format is a map where the key is the variation name and the value is the percentage of users that will see this variation.

You can have as many variations as you want in the percentages, and you can define the percentage of users that will see each variation.

note

If the sum of your percentages is not equal to 100 this is not a problem, we are computing the affectation as fractional numbers.

example: if you have 2 variations and you set variation1: 10 and variation2: 50 it will be equivalent to variation1: 10/60 and variation2: 50/60.

Examples

Define in the default rule

In this example 99% of the users will see the disabled variation and 1% will see the enabled variation.

flag-config.goff.yaml

percentage-flag-1:
  variations:
    disabled: false
    enabled: true
  defaultRule:
    percentage:
      disabled: 99
      enabled: 1

Define in a targeting rule

In this second example, 50% of the users that are admin will see the disabled variation and 50% will see the enabled variation. Non admin users will see the disabled variation.

flag-config.goff.yaml

percentage-flag-1:
  variations:
    disabled: false
    enabled: true
  targeting:
    - query: admin eq true
      percentage:
        disabled: 50
        enabled: 50
  defaultRule:
    variation: disabled

🐥 Canary releases

Percentage rollout are also known as canary releases, where you release a new feature to a small subset of users before rolling it out to everyone.