TUN-4811: Publish quick tunnels' hostname in /metrics under `userHostname` for backwards-compatibility

cmd/cloudflared/tunnel/quick_tunnel.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
+	"strings"
 	"time"
 
 	"github.com/google/uuid"
@@ -51,9 +52,14 @@ func RunQuickTunnel(sc *subcommandContext) error {
 		TunnelName:   data.Result.Name,
 	}
 
+	url := data.Result.Hostname
+	if !strings.HasPrefix(url, "https://") {
+		url = "https://" + url
+	}
+
 	for _, line := range connection.AsciiBox([]string{
 		"Your Quick Tunnel has been created! Visit it at:",
-		data.Result.Hostname,
+		url,
 	}, 2) {
 		sc.log.Info().Msg(line)
 	}

connection/observer.go

@@ -111,6 +111,13 @@ func (o *Observer) sendConnectedEvent(connIndex uint8, location string) {
 
 func (o *Observer) sendURL(url string) {
 	o.sendEvent(Event{EventType: SetURL, URL: url})
+
+	if !strings.HasPrefix(url, "https://") {
+		// We add https:// in the prefix for backwards compatibility as we used to do that with the old free tunnels
+		// and some tools (like `wrangler tail`) are regexp-ing for that specifically.
+		url = "https://" + url
+	}
+	o.metrics.userHostnamesCounts.WithLabelValues(url).Inc()
 }
 
 func (o *Observer) SendReconnect(connIndex uint8) {

connection/observer_test.go

@@ -6,9 +6,28 @@ import (
 	"testing"
 	"time"
 
+	"github.com/prometheus/client_golang/prometheus"
+	dto "github.com/prometheus/client_model/go"
 	"github.com/stretchr/testify/assert"
 )
 
+func TestSendUrl(t *testing.T) {
+	observer := NewObserver(&log, &log, false)
+
+	observer.sendURL("my-url.com")
+	assert.Equal(t, 1.0, getCounterValue(t, observer.metrics.userHostnamesCounts, "https://my-url.com"))
+
+	observer.sendURL("https://another-long-one.com")
+	assert.Equal(t, 1.0, getCounterValue(t, observer.metrics.userHostnamesCounts, "https://another-long-one.com"))
+}
+
+func getCounterValue(t *testing.T, metric *prometheus.CounterVec, val string) float64 {
+	var m = &dto.Metric{}
+	err := metric.WithLabelValues(val).Write(m)
+	assert.NoError(t, err)
+	return m.Counter.GetValue()
+}
+
 func TestRegisterServerLocation(t *testing.T) {
 	m := newTunnelMetrics()
 	tunnels := 20