cs := conn.ConnectionState()
	echo.LatencyField.WriteForRequest(&msgBuilder, requestID, fmt.Sprintf("%v", time.Since(start)))
	echo.CipherField.WriteForRequest(&msgBuilder, requestID, tls.CipherSuiteName(cs.CipherSuite))
	echo.TLSVersionField.WriteForRequest(&msgBuilder, requestID, versionName(cs.Version))
	echo.TLSServerName.WriteForRequest(&msgBuilder, requestID, cs.ServerName)
	echo.AlpnField.WriteForRequest(&msgBuilder, requestID, cs.NegotiatedProtocol)

	var outBuffer bytes.Buffer
	echo.LatencyField.WriteForRequest(&outBuffer, requestID, fmt.Sprintf("%v", time.Since(start)))
	echo.ActiveRequestsField.WriteForRequest(&outBuffer, requestID, fmt.Sprintf("%d", c.e.ActiveRequests()))
	echo.HostnameField.WriteForRequest(&outBuffer, requestID, req.hostname)
	echo.DNSProtocolField.WriteForRequest(&outBuffer, requestID, req.protocol)
	echo.DNSQueryField.WriteForRequest(&outBuffer, requestID, req.query)

	req := cfg.Request
	var outBuffer bytes.Buffer
	echo.ForwarderURLField.WriteForRequest(&outBuffer, requestID, req.Url)

	// Set the special header to trigger the upgrade to WebSocket.
	wsReq := cfg.headers.Clone()
	if len(cfg.hostHeader) > 0 {
		echo.HostField.WriteForRequest(&outBuffer, requestID, hostHeader)
	}
	writeForwardedHeaders(&outBuffer, requestID, wsReq)
	common.SetWebSocketHeader(wsReq)

	httpResp, err := client.Do(httpReq)
	if err != nil {
		return outBuffer.String(), err
	}
	cfg.previousResponse = httpResp

	echo.LatencyField.WriteForRequest(&outBuffer, requestID, fmt.Sprintf("%v", time.Since(start)))
	echo.ActiveRequestsField.WriteForRequest(&outBuffer, requestID, fmt.Sprintf("%d", c.e.ActiveRequests()))

	// Process the response.
	err = processHTTPResponse(requestID, httpResp, &outBuffer)

	f.Write(out, key+":"+value)
}

func (f Field) WriteForRequest(out io.StringWriter, requestID int, value string) {
	_, _ = out.WriteString(fmt.Sprintf("[%d] %s=%s\n", requestID, f, value))
}

func (f Field) WriteKeyValueForRequest(out io.StringWriter, requestID int, key, value string) {
	f.WriteForRequest(out, requestID, key+":"+value)
}

	if err != nil {
		return "", err
	}
	defer func() { _ = conn.Close() }()

	msgBuilder := strings.Builder{}
	echo.ForwarderURLField.WriteForRequest(&msgBuilder, requestID, cfg.Request.Url)

	if cfg.Request.Message != "" {
		echo.ForwarderMessageField.WriteForRequest(&msgBuilder, requestID, cfg.Request.Message)
	}

	// Apply per-request timeout to calculate deadline for reads/writes.

	var header metadata.MD

	resp, err := client.Echo(ctx, grpcReq, grpc.Header(&header))
	if err != nil {
		return "", err
	}

	echo.LatencyField.WriteForRequest(&outBuffer, requestID, fmt.Sprintf("%v", time.Since(start)))
	echo.ActiveRequestsField.WriteForRequest(&outBuffer, requestID, fmt.Sprintf("%d", c.e.ActiveRequests()))

	// When the underlying HTTP2 request returns status 404, GRPC

			fwLog.Warnf("TCP Proxy protocol header write failed: %v", err)
			return msgBuilder.String(), err
		}
	}

	echo.ForwarderURLField.WriteForRequest(&msgBuilder, requestID, cfg.Request.Url)

	if cfg.Request.Message != "" {
		echo.ForwarderMessageField.WriteForRequest(&msgBuilder, requestID, cfg.Request.Message)
	}

	// Apply per-request timeout to calculate deadline for reads/writes.