Method proxyAndRecord

modules/proxy/server.go:146–197

proxyAndRecord forwards the request, records the exchange, and writes the response back.

(ctx context.Context, w io.Writer, req *http.Request, scheme string)

// proxyAndRecord forwards the request, records the exchange, and writes the response back.
func (s *proxyServer) proxyAndRecord(ctx context.Context, w io.Writer, req *http.Request, scheme string) {
	start := time.Now()

	// Capture request body.
	var reqBody []byte
	if req.Body != nil {
		reqBody, _ = io.ReadAll(io.LimitReader(req.Body, maxBodySize+1))
		req.Body = io.NopCloser(strings.NewReader(string(reqBody)))
	}

	// Remove hop-by-hop headers.
	removeHopHeaders(req.Header)

	captured := &capturedRequest{
		Method:  req.Method,
		URI:     req.URL.Path,
		Host:    req.URL.Host,
		Scheme:  scheme,
		Headers: req.Header,
		Query:   req.URL.Query(),
		Body:    reqBody,
	}

	// Forward the request to the real server.
	transport := &http.Transport{
		TLSClientConfig: &tls.Config{},
	}
	resp, err := transport.RoundTrip(req)
	durationMs := float64(time.Since(start).Milliseconds())

	if err != nil {
		// Send 502 back to the client.
		fmt.Fprintf(w, "HTTP/1.1 502 Bad Gateway\r\nContent-Length: 0\r\n\r\n")
		s.storeEvent(ctx, captured, nil, durationMs, err.Error())
		return
	}
	defer resp.Body.Close()

	// Capture response body.
	respBody, _ := io.ReadAll(io.LimitReader(resp.Body, maxBodySize+1))

	capturedResp := &capturedResponse{
		StatusCode: resp.StatusCode,
		Headers:    resp.Header,
		Body:       respBody,
	}

	// Write the response back to the client.
	writeResponse(w, resp, respBody)

	s.storeEvent(ctx, captured, capturedResp, durationMs, "")
}

func writeResponse(w io.Writer, resp *http.Response, body []byte) {
	fmt.Fprintf(w, "HTTP/%d.%d %s\r\n", resp.ProtoMajor, resp.ProtoMinor, resp.Status)