agent: move telemetry out of the run method

command/agent/command.go

@@ -520,81 +520,37 @@ func (cmd *Command) startupJoinWan(agent *Agent, cfg *Config) error {
 	return nil
 }
 
-func (cmd *Command) Run(args []string) int {
+func statsiteSink(config *Config, hostname string) (metrics.MetricSink, error) {
-	cmd.UI = &cli.PrefixedUi{
+	if config.Telemetry.StatsiteAddr == "" {
-		OutputPrefix: "==> ",
+		return nil, nil
-		InfoPrefix:   "    ",
+	}
-		ErrorPrefix:  "==> ",
+	return metrics.NewStatsiteSink(config.Telemetry.StatsiteAddr)
-		Ui:           cmd.UI,
 }
 
-	// Parse our configs
+func statsdSink(config *Config, hostname string) (metrics.MetricSink, error) {
-	cmd.args = args
+	if config.Telemetry.StatsdAddr == "" {
-	config := cmd.readConfig()
+		return nil, nil
-	if config == nil {
+	}
-		return 1
+	return metrics.NewStatsdSink(config.Telemetry.StatsdAddr)
 }
 
-	// Setup the log outputs
+func dogstatdSink(config *Config, hostname string) (metrics.MetricSink, error) {
-	logConfig := &logger.Config{
+	if config.Telemetry.DogStatsdAddr == "" {
-		LogLevel:       config.LogLevel,
+		return nil, nil
-		EnableSyslog:   config.EnableSyslog,
-		SyslogFacility: config.SyslogFacility,
 	}
-	logFilter, logGate, logWriter, logOutput, ok := logger.Setup(logConfig, cmd.UI)
+	sink, err := datadog.NewDogStatsdSink(config.Telemetry.DogStatsdAddr, hostname)
-	if !ok {
-		return 1
-	}
-	cmd.logFilter = logFilter
-	cmd.logOutput = logOutput
-
-	// Setup telemetry
-	// Aggregate on 10 second intervals for 1 minute. Expose the
-	// metrics over stderr when there is a SIGUSR1 received.
-	inm := metrics.NewInmemSink(10*time.Second, time.Minute)
-	metrics.DefaultInmemSignal(inm)
-	metricsConf := metrics.DefaultConfig(config.Telemetry.StatsitePrefix)
-	metricsConf.EnableHostname = !config.Telemetry.DisableHostname
-
-	// Configure the statsite sink
-	var fanout metrics.FanoutSink
-	if config.Telemetry.StatsiteAddr != "" {
-		sink, err := metrics.NewStatsiteSink(config.Telemetry.StatsiteAddr)
 	if err != nil {
-			cmd.UI.Error(fmt.Sprintf("Failed to start statsite sink. Got: %s", err))
+		return nil, err
-			return 1
 	}
-		fanout = append(fanout, sink)
+	sink.SetTags(config.Telemetry.DogStatsdTags)
+	return sink, nil
 }
 
-	// Configure the statsd sink
+func circonusSink(config *Config, hostname string) (metrics.MetricSink, error) {
-	if config.Telemetry.StatsdAddr != "" {
+	if config.Telemetry.CirconusAPIToken == "" && config.Telemetry.CirconusCheckSubmissionURL == "" {
-		sink, err := metrics.NewStatsdSink(config.Telemetry.StatsdAddr)
+		return nil, nil
-		if err != nil {
-			cmd.UI.Error(fmt.Sprintf("Failed to start statsd sink. Got: %s", err))
-			return 1
-		}
-		fanout = append(fanout, sink)
 	}
 
-	// Configure the DogStatsd sink
-	if config.Telemetry.DogStatsdAddr != "" {
-		var tags []string
-
-		if config.Telemetry.DogStatsdTags != nil {
-			tags = config.Telemetry.DogStatsdTags
-		}
-
-		sink, err := datadog.NewDogStatsdSink(config.Telemetry.DogStatsdAddr, metricsConf.HostName)
-		if err != nil {
-			cmd.UI.Error(fmt.Sprintf("Failed to start DogStatsd sink. Got: %s", err))
-			return 1
-		}
-		sink.SetTags(tags)
-		fanout = append(fanout, sink)
-	}
-
-	if config.Telemetry.CirconusAPIToken != "" || config.Telemetry.CirconusCheckSubmissionURL != "" {
 	cfg := &circonus.Config{}
 	cfg.Interval = config.Telemetry.CirconusSubmissionInterval
 	cfg.CheckManager.API.TokenKey = config.Telemetry.CirconusAPIToken
@@ -624,20 +580,87 @@ func (cmd *Command) Run(args []string) int {
 
 	sink, err := circonus.NewCirconusSink(cfg)
 	if err != nil {
-			cmd.UI.Error(fmt.Sprintf("Failed to start Circonus sink. Got: %s", err))
+		return nil, err
-			return 1
 	}
 	sink.Start()
-		fanout = append(fanout, sink)
+	return sink, nil
 }
 
-	// Initialize the global sink
+func startupTelemetry(config *Config) error {
-	if len(fanout) > 0 {
+	// Setup telemetry
-		fanout = append(fanout, inm)
+	// Aggregate on 10 second intervals for 1 minute. Expose the
-		metrics.NewGlobal(metricsConf, fanout)
+	// metrics over stderr when there is a SIGUSR1 received.
+	memSink := metrics.NewInmemSink(10*time.Second, time.Minute)
+	metrics.DefaultInmemSignal(memSink)
+	metricsConf := metrics.DefaultConfig(config.Telemetry.StatsitePrefix)
+	metricsConf.EnableHostname = !config.Telemetry.DisableHostname
+
+	var sinks metrics.FanoutSink
+	addSink := func(name string, fn func(*Config, string) (metrics.MetricSink, error)) error {
+		s, err := fn(config, metricsConf.HostName)
+		if err != nil {
+			return err
+		}
+		if s != nil {
+			sinks = append(sinks, s)
+		}
+		return nil
+	}
+
+	if err := addSink("statsite", statsiteSink); err != nil {
+		return err
+	}
+	if err := addSink("statsd", statsdSink); err != nil {
+		return err
+	}
+	if err := addSink("dogstatd", dogstatdSink); err != nil {
+		return err
+	}
+	if err := addSink("circonus", circonusSink); err != nil {
+		return err
+	}
+
+	if len(sinks) > 0 {
+		sinks = append(sinks, memSink)
+		metrics.NewGlobal(metricsConf, sinks)
 	} else {
 		metricsConf.EnableHostname = false
-		metrics.NewGlobal(metricsConf, inm)
+		metrics.NewGlobal(metricsConf, memSink)
+	}
+	return nil
+}
+
+func (cmd *Command) Run(args []string) int {
+	cmd.UI = &cli.PrefixedUi{
+		OutputPrefix: "==> ",
+		InfoPrefix:   "    ",
+		ErrorPrefix:  "==> ",
+		Ui:           cmd.UI,
+	}
+
+	// Parse our configs
+	cmd.args = args
+	config := cmd.readConfig()
+	if config == nil {
+		return 1
+	}
+
+	// Setup the log outputs
+	logConfig := &logger.Config{
+		LogLevel:       config.LogLevel,
+		EnableSyslog:   config.EnableSyslog,
+		SyslogFacility: config.SyslogFacility,
+	}
+	logFilter, logGate, logWriter, logOutput, ok := logger.Setup(logConfig, cmd.UI)
+	if !ok {
+		return 1
+	}
+	cmd.logFilter = logFilter
+	cmd.logOutput = logOutput
+
+	if err := startupTelemetry(config); err != nil {
+		cmd.UI.Error(err.Error())
+		return 1
 	}
 
 	// Create the agent