block_builder_function.kt

private fun blockBuilder(initializeAction: BBInitializer.() -> Unit) {
    val blockBuilderInitializer = BBInitializer()
    blockBuilderInitializer.initializeAction()

    val jsonResource = blockBuilderInitializer.jsonResource
            ?: throw NullPointerException("jsonResource must be set")

    val remoteFileUrl = blockBuilderInitializer.remoteFileUrl
            ?: throw NullPointerException("remoteFileUrl must be set")

    val context = blockBuilderInitializer.context
            ?: throw NullPointerException("context must be set")

    BlockBuilder
            .configuration(ConfigurationParameters(jsonResource, remoteFileUrl))
            .init(context)
}

private class BBInitializer {

    var context: Context? = null

    @RawRes
    var jsonResource: Int? = null

    var remoteFileUrl: String? = null
}