Method newAdminHandler

admin.go:221–293

newAdminHandler reads admin's config and returns an http.Handler suitable for use in an admin endpoint server, which will be listening on listenAddr.

(addr NetworkAddress, remote bool, ctx Context)

// newAdminHandler reads admin's config and returns an http.Handler suitable
// for use in an admin endpoint server, which will be listening on listenAddr.
func (admin *AdminConfig) newAdminHandler(addr NetworkAddress, remote bool, ctx Context) (adminHandler, error) {
	muxWrap := adminHandler{mux: http.NewServeMux()}

	// secure the local or remote endpoint respectively
	if remote {
		muxWrap.remoteControl = admin.Remote
	} else {
		// see comment in allowedOrigins() as to why we disable the host check for unix/fd networks
		muxWrap.enforceHost = !addr.isWildcardInterface() && !addr.IsUnixNetwork() && !addr.IsFdNetwork()
		muxWrap.allowedOrigins = admin.allowedOrigins(addr)
		muxWrap.enforceOrigin = admin.EnforceOrigin
	}

	addRouteWithMetrics := func(pattern string, handlerLabel string, h http.Handler) {
		labels := prometheus.Labels{"path": pattern, "handler": handlerLabel}
		h = instrumentHandlerCounter(
			adminMetrics.requestCount.MustCurryWith(labels),
			h,
		)
		muxWrap.mux.Handle(pattern, h)
	}
	// addRoute just calls muxWrap.mux.Handle after
	// wrapping the handler with error handling
	addRoute := func(pattern string, handlerLabel string, h AdminHandler) {
		wrapper := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			err := h.ServeHTTP(w, r)
			if err != nil {
				labels := prometheus.Labels{
					"path":    pattern,
					"handler": handlerLabel,
					"method":  strings.ToUpper(r.Method),
				}
				adminMetrics.requestErrors.With(labels).Inc()
			}
			muxWrap.handleError(w, r, err)
		})
		addRouteWithMetrics(pattern, handlerLabel, wrapper)
	}

	const handlerLabel = "admin"

	// register standard config control endpoints
	addRoute("/"+rawConfigKey+"/", handlerLabel, AdminHandlerFunc(handleConfig))
	addRoute("/id/", handlerLabel, AdminHandlerFunc(handleConfigID))
	addRoute("/stop", handlerLabel, AdminHandlerFunc(handleStop))

	// register debugging endpoints
	addRouteWithMetrics("/debug/pprof/", handlerLabel, http.HandlerFunc(pprof.Index))
	addRouteWithMetrics("/debug/pprof/cmdline", handlerLabel, http.HandlerFunc(pprof.Cmdline))
	addRouteWithMetrics("/debug/pprof/profile", handlerLabel, http.HandlerFunc(pprof.Profile))
	addRouteWithMetrics("/debug/pprof/symbol", handlerLabel, http.HandlerFunc(pprof.Symbol))
	addRouteWithMetrics("/debug/pprof/trace", handlerLabel, http.HandlerFunc(pprof.Trace))
	addRouteWithMetrics("/debug/vars", handlerLabel, expvar.Handler())

	// register third-party module endpoints
	for _, m := range GetModules("admin.api") {
		router := m.New().(AdminRouter)