class UppercaseRequestInterceptor : Interceptor {
  @Throws(IOException::class)
  override fun intercept(chain: Chain): Response {
    return chain.proceed(uppercaseRequest(chain.request()))
  }

  /** Returns a request that transforms `request` to be all uppercase.  */
  private fun uppercaseRequest(request: Request): Request {
    val uppercaseBody: RequestBody =
      object : ForwardingRequestBody(request.body) {
        @Throws(IOException::class)