var webSocket: RealWebSocket? = null
    var sourceClosed = false
    var sinkClosed = false
    val closed: Boolean
      get() = sourceClosed && sinkClosed
    var canceled = false

    override val source: BufferedSource =
      object : ForwardingSource(delegate.source) {
        override fun close() {
          sourceClosed = true
          super.close()
        }
      }.buffer()