cmd/k8s-operator: emit event if HTTPS is disabled on Tailnet

Instead of confusing users, emit an event that explicitly tells the
user that HTTPS is disabled on the tailnet and that ingress may not
work until they enable it.

Updates #9141

Signed-off-by: Maisem Ali <maisem@tailscale.com>

cmd/k8s-operator/ingress.go

@@ -125,6 +125,10 @@ func (a *IngressReconciler) maybeProvision(ctx context.Context, logger *zap.Suga
 	gaugeIngressResources.Set(int64(a.managedIngresses.Len()))
 	a.mu.Unlock()
 
+	if !a.ssr.IsHTTPSEnabledOnTailnet() {
+		a.recorder.Event(ing, corev1.EventTypeWarning, "HTTPSNotEnabled", "HTTPS is not enabled on the tailnet; ingress may not work")
+	}
+
 	// magic443 is a fake hostname that we can use to tell containerboot to swap
 	// out with the real hostname once it's known.
 	const magic443 = "${TS_CERT_DOMAIN}:443"

cmd/k8s-operator/operator.go

@@ -73,7 +73,7 @@ func main() {
 	if shouldRunAuthProxy {
 		launchAuthProxy(zlog, restConfig, s)
 	}
-	startReconcilers(zlog, tsNamespace, restConfig, tsClient, image, priorityClassName, tags)
+	startReconcilers(zlog, s, tsNamespace, restConfig, tsClient, image, priorityClassName, tags)
 }
 
 // initTSNet initializes the tsnet.Server and logs in to Tailscale. It uses the
@@ -182,7 +182,7 @@ waitOnline:
 
 // startReconcilers starts the controller-runtime manager and registers the
 // ServiceReconciler.
-func startReconcilers(zlog *zap.SugaredLogger, tsNamespace string, restConfig *rest.Config, tsClient *tailscale.Client, image, priorityClassName, tags string) {
+func startReconcilers(zlog *zap.SugaredLogger, s *tsnet.Server, tsNamespace string, restConfig *rest.Config, tsClient *tailscale.Client, image, priorityClassName, tags string) {
 	var (
 		isDefaultLoadBalancer = defaultBool("OPERATOR_DEFAULT_LOAD_BALANCER", false)
 	)
@@ -225,6 +225,7 @@ func startReconcilers(zlog *zap.SugaredLogger, tsNamespace string, restConfig *r
 	eventRecorder := mgr.GetEventRecorderFor("tailscale-operator")
 	ssr := &tailscaleSTSReconciler{
 		Client:                 mgr.GetClient(),
+		tsnetServer:            s,
 		tsClient:               tsClient,
 		defaultTags:            strings.Split(tags, ","),
 		operatorNamespace:      tsNamespace,

cmd/k8s-operator/sts.go

@@ -24,6 +24,7 @@ import (
 	"tailscale.com/client/tailscale"
 	"tailscale.com/ipn"
 	"tailscale.com/tailcfg"
+	"tailscale.com/tsnet"
 	"tailscale.com/types/opt"
 	"tailscale.com/util/dnsname"
 	"tailscale.com/util/mak"
@@ -71,6 +72,7 @@ type tailscaleSTSConfig struct {
 
 type tailscaleSTSReconciler struct {
 	client.Client
+	tsnetServer            *tsnet.Server
 	tsClient               tsClient
 	defaultTags            []string
 	operatorNamespace      string
@@ -78,6 +80,11 @@ type tailscaleSTSReconciler struct {
 	proxyPriorityClassName string
 }
 
+// IsHTTPSEnabledOnTailnet reports whether HTTPS is enabled on the tailnet.
+func (a *tailscaleSTSReconciler) IsHTTPSEnabledOnTailnet() bool {
+	return len(a.tsnetServer.CertDomains()) > 0
+}
+
 // Provision ensures that the StatefulSet for the given service is running and
 // up to date.
 func (a *tailscaleSTSReconciler) Provision(ctx context.Context, logger *zap.SugaredLogger, sts *tailscaleSTSConfig) (*corev1.Service, error) {