Creating flag variations

This topic explains how to create and edit your feature flag’s variations and outlines the different types of flag variations. Feature flag variations determine what a context or user receives when they encounter a feature flag. Some aspects of flags are consistent across environments, and others are environment-specific:

• A flag’s variations and variation values are consistent across all environments in a project. For example, if a flag has three variations of A, B, and C, those three variations appear in all environments within your project. If you add a new flag variation, it is immediately available in all environments.
• Flag targeting rules are environment-specific. If you change the default targeting rule to serve a different variation, the targeting change only applies to the current environment, such as Staging or Production. To learn more, read Configure the same flag in different environments.

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Flag variations

LaunchDarkly supports boolean and multivariate flags. From the flag’s Variations tab, you can add, edit, or delete variations of existing flags:

• Boolean flags have two variations: true or false.
• Multivariate flags can have two or more string, number, or JSON variations, depending on the flag type you choose when you create it.

Here is the Variations tab of a multivariate flag:

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Edit flag variations

When you add, delete, or edit a feature flag’s variations, the change impacts all environments within the project.

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Add new variations

To add a new variation to an existing string, number, or JSON flag:

1. Navigate to the flag’s Variations tab.
2. Click New variation.
3. Add a Name, Description, and Value.
4. Click Review and save.

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Delete existing variations

To delete a variation for an existing string, number, or JSON flag:

1. Navigate to the flag’s Variations tab.
2. Click New variation.
3. Click Delete next to the variation you want to remove.
4. Click Review and save.

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Edit existing variations

To edit a flag’s variation values:

1. Navigate to the flag’s Variations tab.
2. Make any variation changes as needed:
   • For boolean flags, you can edit the Name and Description.
   • For number, string, and JSON flags, you can edit the Value, Name, and Description.
3. Click Review and save.

Editing the value of a flag variation in use can impact the contexts receiving that variation. If you edit the value of a variation that is actively in use, a warning displays with information about the variation and the environments it’s used in: A flag variation is considered in use in a particular environment when:

• you have configured the flag to serve that variation to some or all contexts, and
• the flag is actively being evaluated in that environment, with a status of “active” or “launched.”

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Change default flag values

When you create a feature flag, some of its values are designated as defaults. A flag’s default values are the values that are served when targeting is on or off, unless you specify otherwise. The default value when a flag is On can be either a single variation or a rollout. The default value when a flag is Off can be only a single variation. For example, a boolean flag could have true set as its default rule when on and false set as its default off variation. A multivariate flag could have variation 2 set as its default rule when on and variation 1 set as its default off variation, with variation 3 and variation 4 configured to appear when contexts match certain targeting rules. Default values are designated automatically every time you create a feature flag. You can accept the default values or change them. When you change the default values and save a flag, you create the flag across all environments in your project with these values set as its defaults. Here is an image of a flag’s default values: To change a flag’s default values for new environments:

1. Click the pencil icon next to “Variations” in the flag’s right sidebar. The Variations tab opens.
2. In the “Default variations for new environments” section, update the variations as needed.
3. Click Review and save.

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Multivariate flags

Multivariate flags let you use one flag to serve more than two variations of a feature simultaneously. There is no limit to the number of variations you can add to a multivariate flag, making it useful for complex use cases and for managing multiple variations of a feature. Multivariate flag variation types include string, number, and JSON. To learn more, read Understanding flag types in the SDK documentation. You can use multivariate flags to target multiple sets of contexts and provide different variations to each. In the following example, the first rule serves Two-click checkout to all customers whose country is US. The second rule serves One-click checkout to all customers whose email ends with .edu. All customers not targeted in the custom rules are served the default rule. Here is an image of a flag with custom rules: To learn more about targeting rules, read Target with flags. You can also use multivariate flags to perform testing with LaunchDarkly Experimentation. To learn more, read Creating Experiments.

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JSON schema for multivariate flag variations

You can use a JSON schema to validate multivariate flag variations to help ensure type safety, enforce naming conventions, and restrict value options for specific fields. To use a JSON schema for a new flag, click the Schema button in the flag creation dialog: A “Schema validation” section appears. Click the magic wand icon to suggest a JSON schema based on your existing variation values. Click the broom icon to format the JSON schema. After you save the new flag, LaunchDarkly validates the flag’s individual variation values against the schema. To add a JSON schema to an existing flag, navigate to its Variations tab and click Add schema.