Method mapRequest

proxy/proxy.go:660–724

creates an outgoing http request to be forwarded to the route endpoint based on the augmented incoming request

(ctx *context, requestContext stdlibcontext.Context)

// creates an outgoing http request to be forwarded to the route endpoint
// based on the augmented incoming request
func (p *Proxy) mapRequest(ctx *context, requestContext stdlibcontext.Context) (*http.Request, routing.Metrics, error) {
	var endpointMetrics routing.Metrics
	r := ctx.request
	rt := ctx.route
	host := ctx.outgoingHost
	stateBag := ctx.StateBag()
	u := r.URL

	switch rt.BackendType {
	case eskip.DynamicBackend:
		setRequestURLFromRequest(u, r)
		setRequestURLForDynamicBackend(u, stateBag)
	case eskip.LBBackend:
		endpoint := p.selectEndpoint(ctx)
		endpointMetrics = endpoint.Metrics
		u.Scheme = endpoint.Scheme
		u.Host = endpoint.Host
	case eskip.NetworkBackend:
		endpointMetrics = p.registry.GetMetrics(rt.Host)
		fallthrough
	default:
		u.Scheme = rt.Scheme
		u.Host = rt.Host
	}

	body := r.Body
	if r.ContentLength == 0 {
		body = nil
	}

	rr, err := http.NewRequestWithContext(requestContext, r.Method, u.String(), body)
	if err != nil {
		return nil, nil, err
	}

	rr.ContentLength = r.ContentLength
	if p.flags.HopHeadersRemoval() {
		rr.Header = cloneHeaderExcluding(r.Header, hopHeaders)
	} else {
		rr.Header = cloneHeader(r.Header)
	}
	// Disable default net/http user agent when user agent is not specified
	if _, ok := rr.Header["User-Agent"]; !ok {
		rr.Header["User-Agent"] = []string{""}
	}
	rr.Host = host

	// If there is basic auth configured in the URL we add them as headers
	if u.User != nil {
		up := u.User.String()
		upBase64 := base64.StdEncoding.EncodeToString([]byte(up))
		rr.Header.Add("Authorization", fmt.Sprintf("Basic %s", upBase64))
	}

	ctxspan := ot.SpanFromContext(r.Context())
	if ctxspan != nil {
		rr = rr.WithContext(ot.ContextWithSpan(rr.Context(), ctxspan))
	}