Add --metrics-port flag. (#87)

* Add --metrics-port flag. Metrics listeners on a random port is unlikely to be useful. * Bind to frontend IP for metrics so they can be scraped.
temporalio · Jul 7, 2022 · 80ecd27 · 80ecd27
1 parent dcd539d
commit 80ecd27
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Showing 3 changed files with 50 additions and 26 deletions.
diff --git a/cmd/temporalite/main.go b/cmd/temporalite/main.go
@@ -35,17 +35,18 @@ var (
 )
 
 const (
-	ephemeralFlag = "ephemeral"
-	dbPathFlag    = "filename"
-	portFlag      = "port"
-	uiPortFlag    = "ui-port"
-	headlessFlag  = "headless"
-	ipFlag        = "ip"
-	logFormatFlag = "log-format"
-	logLevelFlag  = "log-level"
-	namespaceFlag = "namespace"
-	pragmaFlag    = "sqlite-pragma"
-	configFlag    = "config"
+	ephemeralFlag   = "ephemeral"
+	dbPathFlag      = "filename"
+	portFlag        = "port"
+	metricsPortFlag = "metrics-port"
+	uiPortFlag      = "ui-port"
+	headlessFlag    = "headless"
+	ipFlag          = "ip"
+	logFormatFlag   = "log-format"
+	logLevelFlag    = "log-level"
+	namespaceFlag   = "namespace"
+	pragmaFlag      = "sqlite-pragma"
+	configFlag      = "config"
 )
 
 func init() {
@@ -93,6 +94,11 @@ func buildCLI() *cli.App {
 					Usage:   "port for the temporal-frontend GRPC service",
 					Value:   liteconfig.DefaultFrontendPort,
 				},
+				&cli.IntFlag{
+					Name:  metricsPortFlag,
+					Usage: "port for the metrics listener",
+					Value: liteconfig.DefaultMetricsPort,
+				},
 				&cli.IntFlag{
 					Name:        uiPortFlag,
 					Usage:       "port for the temporal web UI",
@@ -171,9 +177,10 @@ func buildCLI() *cli.App {
 			},
 			Action: func(c *cli.Context) error {
 				var (
-					ip         = c.String(ipFlag)
-					serverPort = c.Int(portFlag)
-					uiPort     = serverPort + 1000
+					ip          = c.String(ipFlag)
+					serverPort  = c.Int(portFlag)
+					metricsPort = c.Int(metricsPortFlag)
+					uiPort      = serverPort + 1000
 				)
 
 				if c.IsSet(uiPortFlag) {
@@ -196,6 +203,7 @@ func buildCLI() *cli.App {
 				opts := []temporalite.ServerOption{
 					temporalite.WithDynamicPorts(),
 					temporalite.WithFrontendPort(serverPort),
+					temporalite.WithMetricsPort(metricsPort),
 					temporalite.WithFrontendIP(ip),
 					temporalite.WithDatabaseFilePath(c.String(dbPathFlag)),
 					temporalite.WithNamespaces(c.StringSlice(namespaceFlag)...),

diff --git a/internal/liteconfig/config.go b/internal/liteconfig/config.go
@@ -24,6 +24,7 @@ const (
 	broadcastAddress     = "127.0.0.1"
 	PersistenceStoreName = "sqlite-default"
 	DefaultFrontendPort  = 7233
+	DefaultMetricsPort   = 0
 )
 
 // UIServer abstracts the github.com/temporalio/ui-server project to
@@ -48,6 +49,7 @@ type Config struct {
 	Ephemeral        bool
 	DatabaseFilePath string
 	FrontendPort     int
+	MetricsPort      int
 	DynamicPorts     bool
 	Namespaces       []string
 	SQLitePragmas    map[string]string
@@ -83,6 +85,7 @@ func NewDefaultConfig() (*Config, error) {
 		Ephemeral:        false,
 		DatabaseFilePath: filepath.Join(userConfigDir, "temporalite/db/default.db"),
 		FrontendPort:     0,
+		MetricsPort:      0,
 		UIServer:         noopUIServer{},
 		DynamicPorts:     false,
 		Namespaces:       nil,
@@ -122,18 +125,22 @@ func Convert(cfg *Config) *config.Config {
 		sqliteConfig.ConnectAttributes["_"+k] = v
 	}
 
-	var metricsPort, pprofPort int
+	var pprofPort int
 	if cfg.DynamicPorts {
 		if cfg.FrontendPort == 0 {
 			cfg.FrontendPort = cfg.portProvider.mustGetFreePort()
 		}
-		metricsPort = cfg.portProvider.mustGetFreePort()
+		if cfg.MetricsPort == 0 {
+			cfg.MetricsPort = cfg.portProvider.mustGetFreePort()
+		}
 		pprofPort = cfg.portProvider.mustGetFreePort()
 	} else {
 		if cfg.FrontendPort == 0 {
 			cfg.FrontendPort = DefaultFrontendPort
 		}
-		metricsPort = cfg.FrontendPort + 200
+		if cfg.MetricsPort == 0 {
+			cfg.MetricsPort = cfg.FrontendPort + 200
+		}
 		pprofPort = cfg.FrontendPort + 201
 	}
 
@@ -144,7 +151,7 @@ func Convert(cfg *Config) *config.Config {
 	}
 	baseConfig.Global.Metrics = &metrics.Config{
 		Prometheus: &metrics.PrometheusConfig{
-			ListenAddress: fmt.Sprintf("%s:%d", broadcastAddress, metricsPort),
+			ListenAddress: fmt.Sprintf("%s:%d", cfg.FrontendIP, cfg.MetricsPort),
 			HandlerPath:   "/metrics",
 		},
 	}
@@ -207,28 +214,28 @@ func Convert(cfg *Config) *config.Config {
 	return baseConfig
 }
 
-func (o *Config) mustGetService(frontendPortOffset int) config.Service {
+func (cfg *Config) mustGetService(frontendPortOffset int) config.Service {
 	svc := config.Service{
 		RPC: config.RPC{
-			GRPCPort:        o.FrontendPort + frontendPortOffset,
-			MembershipPort:  o.FrontendPort + 100 + frontendPortOffset,
+			GRPCPort:        cfg.FrontendPort + frontendPortOffset,
+			MembershipPort:  cfg.FrontendPort + 100 + frontendPortOffset,
 			BindOnLocalHost: true,
 			BindOnIP:        "",
 		},
 	}
 
 	// Assign any open port when configured to use dynamic ports
-	if o.DynamicPorts {
+	if cfg.DynamicPorts {
 		if frontendPortOffset != 0 {
-			svc.RPC.GRPCPort = o.portProvider.mustGetFreePort()
+			svc.RPC.GRPCPort = cfg.portProvider.mustGetFreePort()
 		}
-		svc.RPC.MembershipPort = o.portProvider.mustGetFreePort()
+		svc.RPC.MembershipPort = cfg.portProvider.mustGetFreePort()
 	}
 
 	// Optionally bind frontend to IPv4 address
-	if frontendPortOffset == 0 && o.FrontendIP != "" {
+	if frontendPortOffset == 0 && cfg.FrontendIP != "" {
 		svc.RPC.BindOnLocalHost = false
-		svc.RPC.BindOnIP = o.FrontendIP
+		svc.RPC.BindOnIP = cfg.FrontendIP
 	}
 
 	return svc

diff --git a/options.go b/options.go
@@ -57,6 +57,15 @@ func WithFrontendPort(port int) ServerOption {
 	})
 }
 
+// WithMetricsPort sets the listening port for metrics.
+//
+// When unspecified, the port will be system-chosen.
+func WithMetricsPort(port int) ServerOption {
+	return newApplyFuncContainer(func(cfg *liteconfig.Config) {
+		cfg.MetricsPort = port
+	})
+}
+
 // WithFrontendIP binds the temporal-frontend GRPC service to a specific IP (eg. `0.0.0.0`)
 // Check net.ParseIP for supported syntax; only IPv4 is supported.
 //