Method proxyHTTPRequest

proxy/proxy.go:186–272

ProxyHTTPRequest proxies requests of underlying type http and websocket to the origin service.

(
	w connection.ResponseWriter,
	tr *tracing.TracedHTTPRequest,
	httpService ingress.HTTPOriginProxy,
	isWebsocket bool,
	disableChunkedEncoding bool,
	logger *zerolog.Logger,
)

// ProxyHTTPRequest proxies requests of underlying type http and websocket to the origin service.
func (p *Proxy) proxyHTTPRequest(
	w connection.ResponseWriter,
	tr *tracing.TracedHTTPRequest,
	httpService ingress.HTTPOriginProxy,
	isWebsocket bool,
	disableChunkedEncoding bool,
	logger *zerolog.Logger,
) error {
	roundTripReq := tr.Request
	if isWebsocket {
		roundTripReq = tr.Clone(tr.Context())
		roundTripReq.Header.Set("Connection", "Upgrade")
		roundTripReq.Header.Set("Upgrade", "websocket")
		roundTripReq.Header.Set("Sec-Websocket-Version", "13")
		roundTripReq.ContentLength = 0
		roundTripReq.Body = nil
	} else {
		// Support for WSGI Servers by switching transfer encoding from chunked to gzip/deflate
		if disableChunkedEncoding {
			roundTripReq.TransferEncoding = []string{"gzip", "deflate"}
			cLength, err := strconv.Atoi(tr.Header.Get("Content-Length"))
			if err == nil {
				roundTripReq.ContentLength = int64(cLength)
			}
		}
		// Request origin to keep connection alive to improve performance
		roundTripReq.Header.Set("Connection", "keep-alive")
	}

	// Set the User-Agent as an empty string if not provided to avoid inserting golang default UA
	if roundTripReq.Header.Get("User-Agent") == "" {
		roundTripReq.Header.Set("User-Agent", "")
	}

	_, ttfbSpan := tr.Tracer().Start(tr.Context(), "ttfb_origin")
	resp, err := httpService.RoundTrip(roundTripReq)
	if err != nil {
		tracing.EndWithErrorStatus(ttfbSpan, err)
		if err := roundTripReq.Context().Err(); err != nil {
			return errors.Wrap(err, "Incoming request ended abruptly")
		}
		return errors.Wrap(err, "Unable to reach the origin service. The service may be down or it may not be responding to traffic from cloudflared")
	}

	tracing.EndWithStatusCode(ttfbSpan, resp.StatusCode)
	defer func() { _ = resp.Body.Close() }()

	headers := make(http.Header, len(resp.Header))
	// copy headers
	for k, v := range resp.Header {
		headers[k] = v
	}

	// Add spans to response header (if available)
	tr.AddSpans(headers)

	err = w.WriteRespHeaders(resp.StatusCode, headers)
	if err != nil {