Contract Testing

The ff4k-contract-test module provides a suite of reusable tests to verify that your custom FeatureStore and PropertyStore implementations adhere to the FF4K specification. This ensures consistency and reliability across different storage backends.

Setup

First, add the contract test dependency to your project.

Gradle (Kotlin DSL)

If you are using the FF4K BOM, you don't need to specify the version:

dependencies {
    testImplementation("com.yonatankarp:ff4k-contract-test")
}

Otherwise, specify the version explicitly:

dependencies {
    testImplementation("com.yonatankarp:ff4k-contract-test:<version>")
}

Testing a Feature Store

To test your custom FeatureStore, create a test class that extends FeatureStoreContractTest and implement the createStore method.

class MyCustomFeatureStoreTest : FeatureStoreContractTest() {

    // This method is called before each test to provide a fresh store instance
    override suspend fun createStore(): FeatureStore {
        // Return a fresh instance of your store
        // If your store relies on an external DB, ensure it's cleaned up here
        return MyCustomFeatureStore()
    }
}

FeatureStoreContractTest runs tests covering: - get, getAll, put, update and delete - the enable, disable and group extension functions - error handling (FeatureNotFoundException, id changes during update) - concurrent update calls not losing writes

Testing a Property Store

Similar to features, you can test your custom PropertyStore by extending PropertyStoreContractTest.

class MyCustomPropertyStoreTest : PropertyStoreContractTest() {
    override suspend fun createStore(): PropertyStore {
        return MyCustomPropertyStore()
    }
}