UserDefaults OpenFeature Provider for Swift

This is yet another OpenFeature provider for UserDefaults.

Installation

Swift Package Manager

In dependencies section of Package.swift add:

dependencies: [
    .package(
        url: "git@github.com:fumito-ito/UserDefaults-OpenFeature-Provider-Swift.git",
        .upToNextMajor(from: "0.0.1")
    ),
]

and in the target dependencies section add:

.product(name: "UserDefaultsOpenFeatureProvider", package: "UserDefaults-OpenFeature-Provider-Swift"),

Usage

Import the UserDefaultsOpenFeatureProvider and OpenFeature modules.

import UserDefaultsOpenFeatureProvider

Create and set provider.

let provider = UserDefaultsOpenFeatureProvider()
let context = MutableContext(targetingKey: "your_targeting_key", structure: MutableStructure())
OpenFeatureAPI.shared.setProvider(provider: provider, initialContext: context)

If not specified, UserDefaults.standard is used.

If you want to use UserDefaults with a specific suiteName, pass an EvaluationContext that returns the suiteName you want to specify for the UserDefaultsOpenFeatureProviderSuiteNameKey key.

struct CustomContext: EvaluationContext {
    var suiteName: String? = "your_suite_name"

    func getValue(key: String) -> OpenFeature.Value? {
        if let suiteName, key == userDefaultsOpenFeatureProviderSuiteNameKey {
            return .string(suiteName)
        }

        return nil
    }
}

let provider = UserDefaultsOpenFeatureProvider()
let context = CustomContext()
provider.initialize(initialContext: context)

Utilities

The UserDefaultsOpenFeatureProvider implements setter functions to store values in UserDefaults. By saving the value through this function, the PROVIDER_CONFIGURATION_CHANGED event can be fired.

let provider = UserDefaultsOpenFeatureProvider()
try provider.setBooleanValue(
    forKey: appendedBoolKey,
    givenCondition: { targetingKey in
        // You can determine the value to be set based on the targeting key.
        return targetingKey == "this_user_is_target"
    },
    with: TestContext())

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.

License

Apache License 2.0