metrics: make metrics endpoint toggleable

app.go

@@ -72,6 +72,7 @@ const (
 type Config struct {
 	ServerURL                      string
 	Addr                           string
+	MetricsEnabled                 bool
 	MetricsAddr                    string
 	GRPCAddr                       string
 	GRPCAllowInsecure              bool
@@ -655,6 +656,7 @@ func (h *Headscale) Serve() error {
 	log.Info().
 		Msgf("listening and serving HTTP on: %s", h.cfg.Addr)
 
+	if h.cfg.MetricsEnabled {
 		promRouter := h.createPrometheusRouter()
 
 		promHTTPServer := &http.Server{
@@ -675,6 +677,7 @@ func (h *Headscale) Serve() error {
 
 		log.Info().
 			Msgf("listening and serving metrics on: %s", h.cfg.MetricsAddr)
+	}
 
 	return errorGroup.Wait()
 }

cmd/headscale/cli/utils.go

@@ -303,6 +303,7 @@ func getHeadscaleConfig() headscale.Config {
 	return headscale.Config{
 		ServerURL:         viper.GetString("server_url"),
 		Addr:              viper.GetString("listen_addr"),
+		MetricsEnabled:    viper.GetBool("metrics_enabled"),
 		MetricsAddr:       viper.GetString("metrics_listen_addr"),
 		GRPCAddr:          viper.GetString("grpc_listen_addr"),
 		GRPCAllowInsecure: viper.GetBool("grpc_allow_insecure"),

cmd/headscale/headscale_test.go

@@ -56,6 +56,7 @@ func (*Suite) TestConfigLoading(c *check.C) {
 	c.Assert(viper.GetString("server_url"), check.Equals, "http://127.0.0.1:8080")
 	c.Assert(viper.GetString("listen_addr"), check.Equals, "0.0.0.0:8080")
 	c.Assert(viper.GetString("metrics_listen_addr"), check.Equals, "127.0.0.1:9915")
+	c.Assert(viper.GetString("metrics_enabled"), check.Equals, "true")
 	c.Assert(viper.GetString("db_type"), check.Equals, "sqlite3")
 	c.Assert(viper.GetString("db_path"), check.Equals, "/var/lib/headscale/db.sqlite")
 	c.Assert(viper.GetString("tls_letsencrypt_hostname"), check.Equals, "")

config-example.yaml

@@ -16,6 +16,9 @@ server_url: http://127.0.0.1:8080
 #
 listen_addr: 0.0.0.0:8080
 
+# Enable Prometheus metrics endpoint
+metrics_enabled: true
+
 # Address to listen to /metrics, you may want
 # to keep this endpoint private to your internal
 # network

docs/examples/kustomize/base/configmap.yaml

@@ -5,5 +5,6 @@ metadata:
 data:
   server_url: $(PUBLIC_PROTO)://$(PUBLIC_HOSTNAME)
   listen_addr: "0.0.0.0:8080"
+  metrics_enabled: "true"
   metrics_listen_addr: "127.0.0.1:9915"
   ephemeral_node_inactivity_timeout: "30m"

docs/examples/kustomize/postgres/deployment.yaml

@@ -30,6 +30,11 @@ spec:
                 configMapKeyRef:
                   name: headscale-config
                   key: metrics_listen_addr
+            - name: METRICS_ENABLED
+              valueFrom:
+                configMapKeyRef:
+                  name: headscale-config
+                  key: metrics_enabled
             - name: DERP_MAP_PATH
               value: /vol/config/derp.yaml
             - name: EPHEMERAL_NODE_INACTIVITY_TIMEOUT

docs/examples/kustomize/sqlite/statefulset.yaml

@@ -31,6 +31,11 @@ spec:
                 configMapKeyRef:
                   name: headscale-config
                   key: metrics_listen_addr
+            - name: METRICS_ENABLED
+              valueFrom:
+                configMapKeyRef:
+                  name: headscale-config
+                  key: metrics_enabled
             - name: DERP_MAP_PATH
               value: /vol/config/derp.yaml
             - name: EPHEMERAL_NODE_INACTIVITY_TIMEOUT

integration_test/etc/config.yaml

@@ -14,6 +14,7 @@ dns_config:
 db_path: /tmp/integration_test_db.sqlite3
 private_key_path: private.key
 listen_addr: 0.0.0.0:8080
+metrics_enabled: true
 metrics_listen_addr: 127.0.0.1:9915
 server_url: http://headscale:8080