var invokeStartEvent = true
    var responseBuilder: Response.Builder? = null
    var sendRequestException: IOException? = null
    val hasRequestBody = HttpMethod.permitsRequestBody(request.method) && requestBody != null
    val isUpgradeRequest =
      !hasRequestBody &&
        "upgrade".equals(request.header("Connection"), ignoreCase = true)
    try {
      exchange.writeRequestHeaders(request)

          peek.doNotReadRequestBody -> {
            hasBody = false // Ignore the body completely.
          }

          contentLength != -1L -> {
            hasBody = contentLength > 0L || HttpMethod.permitsRequestBody(request.method)
            requestBodySink.write(socket.source, contentLength)
          }

          chunked -> {
            chunkSizes = mutableListOf()
            hasBody = true

        if (body == null) {
          require(!HttpMethod.requiresRequestBody(method)) {
            "method $method must have a request body."
          }
        } else {
          require(HttpMethod.permitsRequestBody(method)) {
            "method $method must not have a request body."
          }
        }
        this.method = method
        this.body = body
      }

    /**