TUN-4698: Add cloudflared metrics endpoint to serve quick tunnel hostname

cmd/cloudflared/proxydns/cmd.go

@@ -73,7 +73,7 @@ func Run(c *cli.Context) error {
 		log.Fatal().Err(err).Msg("Failed to open the metrics listener")
 	}
 
-	go metrics.ServeMetrics(metricsListener, nil, nil, log)
+	go metrics.ServeMetrics(metricsListener, nil, nil, "", log)
 
 	listener, err := tunneldns.CreateListener(
 		c.String("address"),

cmd/cloudflared/tunnel/cmd.go

@@ -206,7 +206,7 @@ func runAdhocNamedTunnel(sc *subcommandContext, name, credentialsOutputPath stri
 
 // runClassicTunnel creates a "classic" non-named tunnel
 func runClassicTunnel(sc *subcommandContext) error {
-	return StartServer(sc.c, version, nil, sc.log, sc.isUIEnabled)
+	return StartServer(sc.c, version, nil, sc.log, sc.isUIEnabled, "")
 }
 
 func routeFromFlag(c *cli.Context) (route tunnelstore.Route, ok bool) {
@@ -225,6 +225,7 @@ func StartServer(
 	namedTunnel *connection.NamedTunnelConfig,
 	log *zerolog.Logger,
 	isUIEnabled bool,
+	quickTunnelHostname string,
 ) error {
 	_ = raven.SetDSN(sentryDSN)
 	var wg sync.WaitGroup
@@ -341,7 +342,7 @@ func StartServer(
 		defer wg.Done()
 		readinessServer := metrics.NewReadyServer(log)
 		observer.RegisterSink(readinessServer)
-		errC <- metrics.ServeMetrics(metricsListener, ctx.Done(), readinessServer, log)
+		errC <- metrics.ServeMetrics(metricsListener, ctx.Done(), readinessServer, quickTunnelHostname, log)
 	}()
 
 	if err := ingressRules.StartOrigins(&wg, log, ctx.Done(), errC); err != nil {

cmd/cloudflared/tunnel/quick_tunnel.go

@@ -64,6 +64,7 @@ func RunQuickTunnel(sc *subcommandContext) error {
 		&connection.NamedTunnelConfig{Credentials: credentials},
 		sc.log,
 		sc.isUIEnabled,
+		data.Result.Hostname,
 	)
 }
 

cmd/cloudflared/tunnel/subcommand_context.go

@@ -286,6 +286,7 @@ func (sc *subcommandContext) run(tunnelID uuid.UUID) error {
 		&connection.NamedTunnelConfig{Credentials: credentials},
 		sc.log,
 		sc.isUIEnabled,
+		"",
 	)
 }