Method ServeHTTP

routing/routing.go:332–411

ServeHTTP renders the list of current routes.

(w http.ResponseWriter, req *http.Request)

// ServeHTTP renders the list of current routes.
func (r *Routing) ServeHTTP(w http.ResponseWriter, req *http.Request) {
	if req.Method != "GET" && req.Method != "HEAD" {
		w.WriteHeader(http.StatusMethodNotAllowed)
		return
	}

	rt := r.routeTable.Load().(*routeTable)
	req.ParseForm()
	createdUnix := strconv.FormatInt(rt.created.Unix(), 10)
	ts := req.Form.Get("timestamp")
	if ts != "" && createdUnix != ts {
		http.Error(w, "invalid timestamp", http.StatusBadRequest)
		return
	}

	showInvalid := req.Form.Get("invalid") == "true"

	routes := rt.validRoutes
	if showInvalid {
		routes = rt.invalidRoutes
	}

	if req.Method == "HEAD" {
		w.Header().Set(routesTimestampName, createdUnix)
		w.Header().Set(RoutesCountName, strconv.Itoa(len(routes)))

		if strings.Contains(req.Header.Get("Accept"), "application/json") {
			w.Header().Set("Content-Type", "application/json")
		} else {
			w.Header().Set("Content-Type", "text/plain")
		}

		return
	}

	offset, err := extractParam(req, "offset", 0)
	if err != nil {
		http.Error(w, "invalid offset", http.StatusBadRequest)
		return
	}

	limit, err := extractParam(req, "limit", defaultRouteListingLimit)
	if err != nil {
		http.Error(w, "invalid limit", http.StatusBadRequest)
		return
	}

	w.Header().Set(routesTimestampName, createdUnix)
	w.Header().Set(RoutesCountName, strconv.Itoa(len(routes)))

	paged := slice(routes, offset, limit)
	if strings.Contains(req.Header.Get("Accept"), "application/json") {
		w.Header().Set("Content-Type", "application/json")
		if showInvalid {
			resp := make([]InvalidRouteResponse, len(paged))
			for i, route := range paged {
				resp[i] = InvalidRouteResponse{Route: route, Error: rt.invalidRouteErrors[route.Id]}
			}