func()

in handler/proxy_client.go [89:161]
57 lines of code
16 McCabe index (conditional complexity)

func (p *ProxyClient) Do(req *http.Request) (*http.Response, error) {
	proxyURL := *req.URL
	if p.HostOverride != "" {
		proxyURL.Host = p.HostOverride

	} else {
		proxyURL.Host = req.Host
	}
	proxyURL.Scheme = "https"

	if log.GetLevel() == log.DebugLevel {
		initialReqDump, err := httputil.DumpRequest(req, true)
		if err != nil {
			log.WithError(err).Error("unable to dump request")
		}
		log.WithField("request", string(initialReqDump)).Debug("Initial request dump:")
	}

	proxyReq, err := http.NewRequest(req.Method, proxyURL.String(), req.Body)
	if err != nil {
		return nil, err
	}

	var service *endpoints.ResolvedEndpoint
	if p.SigningNameOverride != "" && p.RegionOverride != "" {
		service = &endpoints.ResolvedEndpoint{URL: fmt.Sprintf("https://%s", proxyURL.Host), SigningMethod: "v4", SigningRegion: p.RegionOverride, SigningName: p.SigningNameOverride}
	} else {
		service = determineAWSServiceFromHost(req.Host)
	}
	if service == nil {
		return nil, fmt.Errorf("unable to determine service from host: %s", req.Host)
	}

	if err := p.sign(proxyReq, service); err != nil {
		return nil, err
	}

	// Remove any headers specified
	for _, header := range p.StripRequestHeaders {
		log.WithField("StripHeader", string(header)).Debug("Stripping Header:")
		req.Header.Del(header)
	}

	// Add origin headers after request is signed (no overwrite)
	copyHeaderWithoutOverwrite(proxyReq.Header, req.Header)

	if log.GetLevel() == log.DebugLevel {
		proxyReqDump, err := httputil.DumpRequest(proxyReq, true)
		if err != nil {
			log.WithError(err).Error("unable to dump request")
		}
		log.WithField("request", string(proxyReqDump)).Debug("proxying request")
	}

	resp, err := p.Client.Do(proxyReq)
	if err != nil {
		return nil, err
	}

	if (p.LogFailedRequest || log.GetLevel() == log.DebugLevel) && resp.StatusCode >= 400 {
		b, _ := ioutil.ReadAll(resp.Body)
		log.WithField("request", fmt.Sprintf("%s %s", proxyReq.Method, proxyReq.URL)).
			WithField("status_code", resp.StatusCode).
			WithField("message", string(b)).
			Error("error proxying request")

		// Need to "reset" the response body because we consumed the stream above, otherwise caller will
		// get empty body.
		resp.Body = ioutil.NopCloser(bytes.NewBuffer(b))
	}

	return resp, nil
}