if (response.isAcknowledged()) {
                    logger.info("[Rebuild] Switched aliases from {} to {}", oldIndexName, newIndexName);
                    return true;
                }
                logger.warn("[Rebuild] Alias switch not acknowledged from {} to {}", oldIndexName, newIndexName);
            }

    assertFailsWith<SocketTimeoutException> {
      source.readByte() // If Content-Length was accurate, this would return -1 immediately.
    }
    source.close()
  }

  /** Confirm that an unacknowledged write times out.  */
  @Test
  fun writeTimeouts() {
    val server = MockWebServer()
    // Sockets on some platforms can have large buffers that mean writes do not block when