agent: statsd support. Fixes #247

CHANGELOG.md

@@ -26,6 +26,7 @@ IMPROVEMENTS:
   * Support for HTTP `?pretty` parameter to pretty format JSON output.
   * Use $SHELL when invoking handlers. [GH-237]
   * Agent takes the `-encrypt` CLI Flag [GH-245]
+  * New `statsd_add` config for Statsd support. [GH-247]
 
 BUG FIXES:
 

command/agent/command.go

@@ -347,16 +347,31 @@ func (c *Command) Run(args []string) int {
 	metrics.DefaultInmemSignal(inm)
 	metricsConf := metrics.DefaultConfig("consul")
 
-	// Optionally configure a statsite sink if provided
+	// Configure the statsite sink
+	var fanout metrics.FanoutSink
 	if config.StatsiteAddr != "" {
 		sink, err := metrics.NewStatsiteSink(config.StatsiteAddr)
 		if err != nil {
 			c.Ui.Error(fmt.Sprintf("Failed to start statsite sink. Got: %s", err))
 			return 1
 		}
-		fanout := metrics.FanoutSink{inm, sink}
-		metrics.NewGlobal(metricsConf, fanout)
+		fanout = append(fanout, sink)
+	}
 
+	// Configure the statsd sink
+	if config.StatsdAddr != "" {
+		sink, err := metrics.NewStatsdSink(config.StatsdAddr)
+		if err != nil {
+			c.Ui.Error(fmt.Sprintf("Failed to start statsd sink. Got: %s", err))
+			return 1
+		}
+		fanout = append(fanout, sink)
+	}
+
+	// Initialize the global sink
+	if len(fanout) > 0 {
+		fanout = append(fanout, inm)
+		metrics.NewGlobal(metricsConf, fanout)
 	} else {
 		metricsConf.EnableHostname = false
 		metrics.NewGlobal(metricsConf, inm)

command/agent/config.go

@@ -129,6 +129,10 @@ type Config struct {
 	// metrics will be streamed to that instance.
 	StatsiteAddr string `mapstructure:"statsite_addr"`
 
+	// StatsdAddr is the address of a statsd instance. If provided,
+	// metrics will be sent to that instance.
+	StatsdAddr string `mapstructure:"statsd_addr"`
+
 	// Protocol is the Consul protocol version to use.
 	Protocol int `mapstructure:"protocol"`
 
@@ -575,6 +579,9 @@ func MergeConfig(a, b *Config) *Config {
 	if b.StatsiteAddr != "" {
 		result.StatsiteAddr = b.StatsiteAddr
 	}
+	if b.StatsdAddr != "" {
+		result.StatsdAddr = b.StatsdAddr
+	}
 	if b.EnableDebug {
 		result.EnableDebug = true
 	}

command/agent/config_test.go

@@ -416,6 +416,20 @@ func TestDecodeConfig(t *testing.T) {
 	if !config.DisableRemoteExec {
 		t.Fatalf("bad: %#v", config)
 	}
+
+	// stats(d|ite) exec
+	input = `{"statsite_addr": "127.0.0.1:7250", "statsd_addr": "127.0.0.1:7251"}`
+	config, err = DecodeConfig(bytes.NewReader([]byte(input)))
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if config.StatsiteAddr != "127.0.0.1:7250" {
+		t.Fatalf("bad: %#v", config)
+	}
+	if config.StatsdAddr != "127.0.0.1:7251" {
+		t.Fatalf("bad: %#v", config)
+	}
 }
 
 func TestDecodeConfig_Service(t *testing.T) {
@@ -578,6 +592,8 @@ func TestMergeConfig(t *testing.T) {
 			},
 		},
 		DisableRemoteExec: true,
+		StatsiteAddr:      "127.0.0.1:7250",
+		StatsdAddr:        "127.0.0.1:7251",
 	}
 
 	c := MergeConfig(a, b)

website/source/docs/agent/options.html.markdown

@@ -309,9 +309,15 @@ definitions support being updated during a reload.
 * `start_join` - An array of strings specifying addresses of nodes to
   join upon startup.
 
+* `statsd_addr` - This provides the address of a statsd instance.  If provided
+  Consul will send various telemetry information to that instance for aggregation.
+  This can be used to capture various runtime information. This sends UDP packets
+  only, and can be used with statsd or statsite.
+
 * `statsite_addr` - This provides the address of a statsite instance. If provided
   Consul will stream various telemetry information to that instance for aggregation.
-  This can be used to capture various runtime information.
+  This can be used to capture various runtime information. This streams via
+  TCP and can only be used with statsite.
 
 * `syslog_facility` - When `enable_syslog` is provided, this controls which
   facility messages are sent to. By default, `LOCAL0` will be used.