Add DogStatsd configuration

command/agent/command.go

@@ -15,6 +15,8 @@ import (
 	"time"
 
 	"github.com/armon/go-metrics"
+	"github.com/armon/go-metrics/datadog"
+	"github.com/hashicorp/consul-migrate/migrator"
 	"github.com/hashicorp/consul/watch"
 	"github.com/hashicorp/go-checkpoint"
 	"github.com/hashicorp/go-syslog"
@@ -604,6 +606,23 @@ func (c *Command) Run(args []string) int {
 		fanout = append(fanout, sink)
 	}
 
+	// Configure the DogStatsd sink
+	if config.DogStatsdAddr != "" {
+		var tags []string
+
+		if config.DogStatsdTags != nil {
+			tags = config.DogStatsdTags
+		}
+
+		sink, err := datadog.NewDogStatsdSink(config.DogStatsdAddr, metricsConf.HostName)
+		if err != nil {
+			c.Ui.Error(fmt.Sprintf("Failed to start DogStatsd sink. Got: %s", err))
+			return 1
+		}
+		sink.SetTags(tags)
+		fanout = append(fanout, sink)
+	}
+
 	// Initialize the global sink
 	if len(fanout) > 0 {
 		fanout = append(fanout, inm)

command/agent/config.go

@@ -184,6 +184,14 @@ type Config struct {
 	// metrics will be sent to that instance.
 	StatsdAddr string `mapstructure:"statsd_addr"`
 
+	// DogStatsdAddr is the address of a dogstatsd instance. If provided,
+	// metrics will be sent to that instance
+	DogStatsdAddr string `mapstructure:"dogstatsd_addr"`
+
+	// DogStatsdTags are the global tags that should be sent with each packet to dogstatsd
+	// It is a list of strings, where each string looks like "my_tag_name:my_tag_value"
+	DogStatsdTags []string `mapstructure:"dogstatsd_tags"`
+
 	// Protocol is the Consul protocol version to use.
 	Protocol int `mapstructure:"protocol"`
 
@@ -916,6 +924,12 @@ func MergeConfig(a, b *Config) *Config {
 	if b.StatsdAddr != "" {
 		result.StatsdAddr = b.StatsdAddr
 	}
+	if b.DogStatsdAddr != "" {
+		result.DogStatsdAddr = b.DogStatsdAddr
+	}
+	if b.DogStatsdTags != nil {
+		result.DogStatsdTags = b.DogStatsdTags
+	}
 	if b.EnableDebug {
 		result.EnableDebug = true
 	}

command/agent/config_test.go

@@ -629,6 +629,28 @@ func TestDecodeConfig(t *testing.T) {
 		t.Fatalf("bad: %#v", config)
 	}
 
+	// dogstatsd
+	input = `{"dogstatsd_addr": "127.0.0.1:7254", "dogstatsd_tags":["tag_1:val_1", "tag_2:val_2"]}`
+	config, err = DecodeConfig(bytes.NewReader([]byte(input)))
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	if config.DogStatsdAddr != "127.0.0.1:7254" {
+		t.Fatalf("bad: %#v", config)
+	}
+
+	if len(config.DogStatsdTags) != 2 {
+		t.Fatalf("bad: %#v", config)
+	}
+
+	if config.DogStatsdTags[0] != "tag_1:val_1" {
+		t.Fatalf("bad: %#v", config)
+	}
+
+	if config.DogStatsdTags[1] != "tag_2:val_2" {
+		t.Fatalf("bad: %#v", config)
+	}
+
 	// Statsite prefix
 	input = `{"statsite_prefix": "my_prefix"}`
 	config, err = DecodeConfig(bytes.NewReader([]byte(input)))
@@ -1216,6 +1238,8 @@ func TestMergeConfig(t *testing.T) {
 		StatsiteAddr:              "127.0.0.1:7250",
 		StatsitePrefix:            "stats_prefix",
 		StatsdAddr:                "127.0.0.1:7251",
+		DogStatsdAddr:             "127.0.0.1:7254",
+		DogStatsdTags:             []string{"tag_1:val_1", "tag_2:val_2"},
 		DisableUpdateCheck:        true,
 		DisableAnonymousSignature: true,
 		HTTPAPIResponseHeaders: map[string]string{