Allow listening on specific IP addresses

Signed-off-by: Julien Pivotto <[email protected]>

conf/example.conf

@@ -10,6 +10,9 @@
     # listen_port defines the port on which Trickster's Proxy server listens.
     # since this is a proxy for Prometheus, we use 9090 by default, just like Prometheus does
     # listen_port = 9090
+    # listen_address defines the ip on which Trickster's Proxy server listens.
+    # empty by default, listening on all interfaces
+    # listen_address =
 
 [cache]
     # cache_type defines what kind of cache Trickster uses
@@ -82,6 +85,9 @@
 
     # listen_port defines the port that Trickster's metrics server listens on at /metrics
     listen_port = 8082
+    # listen_address defines the ip that Trickster's metrics server listens on at /metrics
+    # empty by default, listening on all interfaces
+    # listen_address =
 
 # Configuration Options for Logging Instrumentation
 [logging]

config.go

@@ -29,6 +29,9 @@ type GeneralConfig struct {
 
 // ProxyServerConfig is a collection of configurations for the main http listener for the application
 type ProxyServerConfig struct {
+	// ListenAddress is IP address for the main http listener for the application
+	ListenAddress string `toml:"listen_address"`
+	// ListenPort is TCP Port for the main http listener for the application
 	ListenPort int `toml:"listen_port"`
 }
 
@@ -70,6 +73,8 @@ type PrometheusOriginConfig struct {
 
 // MetricsConfig is a collection of Metrics Collection configurations
 type MetricsConfig struct {
+	// ListenAddress is IP address from which the Application Metrics are available for pulling at /metrics
+	ListenAddress string `toml:"listen_address"`
 	// ListenPort is TCP Port from which the Application Metrics are available for pulling at /metrics
 	ListenPort int `toml:"listen_port"`
 }

main.go

@@ -66,9 +66,9 @@ func main() {
 	// Catch All for Single-Origin proxy
 	router.PathPrefix("/").HandlerFunc(t.promFullProxyHandler).Methods("GET")
 
-	level.Info(t.Logger).Log("event", "proxy http endpoint starting", "port", t.Config.ProxyServer.ListenPort)
+	level.Info(t.Logger).Log("event", "proxy http endpoint starting", "address", t.Config.ProxyServer.ListenAddress, "port", t.Config.ProxyServer.ListenPort)
 
 	// Start the Server
-	err := http.ListenAndServe(fmt.Sprintf(":%d", t.Config.ProxyServer.ListenPort), handlers.CompressHandler(router))
+	err := http.ListenAndServe(fmt.Sprintf("%s:%d", t.Config.ProxyServer.ListenAddress, t.Config.ProxyServer.ListenPort), handlers.CompressHandler(router))
 	level.Error(t.Logger).Log("event", "exiting", "err", err)
 }

metrics.go

@@ -61,10 +61,10 @@ func NewApplicationMetrics(config *Config, logger log.Logger) *ApplicationMetric
 	if config.Metrics.ListenPort > 0 {
 		go func() {
 
-			level.Info(logger).Log("event", "metrics http endpoint starting", "port", fmt.Sprintf("%d", config.Metrics.ListenPort))
+			level.Info(logger).Log("event", "metrics http endpoint starting", "address", config.Metrics.ListenAddress, "port", fmt.Sprintf("%d", config.Metrics.ListenPort))
 
 			http.Handle("/metrics", promhttp.Handler())
-			if err := http.ListenAndServe(fmt.Sprintf(":%d", config.Metrics.ListenPort), nil); err != nil {
+			if err := http.ListenAndServe(fmt.Sprintf("%s:%d", config.Metrics.ListenAddress, config.Metrics.ListenPort), nil); err != nil {
 				level.Error(logger).Log("event", "unable to start metrics http server", "detail", err.Error())
 				os.Exit(1)
 			}