ServiceClient.kt

class ServiceClient(val userAgent: String, val rateLimit: Float = 1.0f) {

  // ref https://github.com/kittinunf/Fuel
  private val fuelManager = FuelManager()
  private var previousDispatchTime = Instant.now()

  init {
    fuelManager.basePath = "https://my-service.com"
    fuelManager.baseHeaders = mapOf("User-Agent" to userAgent)
    fuelManager.addRequestInterceptor {
      // rate-limit requests
      synchronized(previousDispatchTime) {
        if (Instant.now().minus(previousDispatchTime.millis).millis > (1.0 / rateLimit * 1000.0).toLong()) {
          Thread.sleep((1.0 / rateLimit * 1000.0).roundToLong())
        }
        previousDispatchTime = Instant.now()
      }
      it
    }
  }
}