"CallEnd",
    )
  }

  private fun newEventSource(accept: String? = null): EventSource {
    val builder =
      Request.Builder()
        .url(server.url("/"))
    if (accept != null) {
      builder.header("Accept", accept)
    }
    val request = builder.build()
    val factory = createFactory(client)
    return factory.newEventSource(request, listener)
  }

     * asynchronous process to connect the socket. Once that succeeds or fails, `listener` will be
     * notified. The caller must cancel the returned event source when it is no longer in use.
     */
    fun newEventSource(
      request: Request,
      listener: EventSourceListener,
    ): EventSource
  }