Secrets and Build Config

Understand how store secrets in local.properties and share the secrets in all the platforms (Android, iOS, Web, Desktop)

AppKickstarter leverages BuildKonfig to store secrets and dispatch them in all platforms.

For example we have in local.properties this secret:

# Google Sign in
google_sign_in_web_client_id=

In Shared module (build.gradle file) we get the local.properties secrets and create usable constants:

buildkonfig {
    packageName = "com.appkickstarter.shared"

    val props = Properties()

    try {
        props.load(file("../local.properties").inputStream())
    } catch (e: Exception) {
        // keys are private and can not be committed to git
    }

    defaultConfigs {
        buildConfigField(
            STRING,
            "GOOGLE_SIGN_IN_WEB_CLIENT_ID",
            props["google_sign_in_web_client_id"]?.toString() ?: ""
        )
    }
}

This way we can use in Kotlin code (multiplatform) :

private fun initGoogleAuth() {
    val credentials = GoogleAuthCredentials(serverId = BuildKonfig.GOOGLE_SIGN_IN_WEB_CLIENT_ID)
    ...
}