experiment-generator

A code generator for use with Anvil-KSP that simplifies injection of the A/B experiments with a @ContributesExperiment / @ContributesExperimentVariantSerializer annotations.

ContributesExperiment and ContributesExperimentVariantSerializer annotations used to simplify creation of feature flags in different modules and adding them to a feature manager.

Code generator setup

Before using the generator, make sure Anvil-KSP is already configured in the project.

Then add the required dependencies:

dependencies {
    ksp("ru.pixnews.anvil.ksp.codegen:experiment-generator:0.1")

    implementation("ru.pixnews.anvil.ksp.codegen:experiment-inject:0.1")
}

Project setup

To make use of this generator's output, the project must have injection set up using Dagger multibindings. The configuration might look something like this (using classes from the experiment-inject module).

Create component with experiments:

import ru.pixnews.anvil.ksp.codegen.experiment.inject.ExperimentScope

@SingleIn(ExperimentScope::class)
@MergeComponent(scope = ExperimentScope::class)
interface ExperimentsComponent {
    fun appExperiments(): DaggerSet<Experiment>

    fun appExperimentVariantSerializers(): DaggerMap<ExperimentKey, ExperimentVariantSerializer>

    companion object {
        operator fun invoke(): ExperimentsComponent = DaggerExperimentsComponent.create()
    }
}

Module:

import ru.pixnews.anvil.ksp.codegen.experiment.inject.ExperimentScope

@Module
@ContributesTo(ExperimentScope::class)
abstract class ExperimentsModule {
    @Multibinds
    abstract fun appExperiments(): DaggerSet<Experiment>

    @Multibinds
    abstract fun appExperimentSerializers(): DaggerMap<String, ExperimentVariantSerializer>
}

Usage

Annotate experiment with @ContributesExperiment and serializer with @ContributesExperimentSerializer:

@ContributesExperiment
object DarkModeExperiment : Experiment {
    …

    @ContributesExperimentVariantSerializer("ui.dark_mode")
    object Serializer : BooleanVariantSerializer(…)

}

The following binding will be generated based on this annotation:

@Module
@ContributesTo(ExperimentScope::class)
object DarkModeExperiment_Experiments_Module {
  @Provides
  @IntoSet
  fun provideDarkModeExperiment(): Experiment = DarkModeExperiment

  @Provides
  @IntoMap
  @ExperimentVariantMapKey(key = "ui.dark_mode")
  fun provideSerializer(): ExperimentVariantSerializer = DarkModeExperiment.Serializer
}

Packages

ru.pixnews.anvil.ksp.codegen.experiment.generator

jvm