Added heartbeat stat (#6)

stats/aggregate_test.go

@@ -71,15 +71,13 @@ func TestAggregateStatter_Inc(t *testing.T) {
 	m.On("Close").Return(nil)
 	s := stats.NewAggregateStatter(m, time.Millisecond)
 
-	time.Sleep(time.Millisecond)
-
 	s.Inc("test", 1, 1.0, "foo", "bar")
 	s.Inc("test", 1, 1.0, "foo", "bar")
 	s.Inc("test1", 1, 1.0, "foo", "bar")
 	s.Inc("test", 1, 1.0, "foo1", "bar")
 	s.Inc("rate", 1, 0.1)
 
-	time.Sleep(2 * time.Millisecond)
+	time.Sleep(10 * time.Millisecond)
 
 	_ = s.Close()
 
@@ -94,14 +92,12 @@ func TestAggregateStatter_Gauge(t *testing.T) {
 	m.On("Close").Return(nil)
 	s := stats.NewAggregateStatter(m, time.Millisecond)
 
-	time.Sleep(time.Millisecond)
-
 	s.Gauge("test", 1, 1.0, "foo", "bar")
 	s.Gauge("test", 3, 1.0, "foo", "bar")
 	s.Gauge("test1", 4, 1.0, "foo", "bar")
 	s.Gauge("test", 5, 1.0, "foo1", "bar")
 
-	time.Sleep(2 * time.Millisecond)
+	time.Sleep(10 * time.Millisecond)
 
 	_ = s.Close()
 
@@ -117,15 +113,13 @@ func TestAggregateStatter_Timing(t *testing.T) {
 	m.On("Close").Return(nil)
 	s := stats.NewAggregateStatter(m, time.Millisecond)
 
-	time.Sleep(time.Millisecond)
-
 	s.Timing("test", time.Millisecond, 1.0, "foo", "bar")
 	s.Timing("test", time.Second, 1.0, "foo", "bar")
 	s.Timing("test1", time.Millisecond, 1.0, "foo", "bar")
 	s.Timing("test", time.Millisecond, 1.0, "foo1", "bar")
 	s.Timing("rate", time.Millisecond, 0.1)
 
-	time.Sleep(2 * time.Millisecond)
+	time.Sleep(10 * time.Millisecond)
 
 	_ = s.Close()
 

stats/heartbeat.go

@@ -0,0 +1,26 @@
+package stats
+
+import (
+	"time"
+)
+
+// DefaultHeartbeatInterval is the default heartbeat ticker interval.
+var DefaultHeartbeatInterval = time.Second
+
+// Heartbeat enters a loop, reporting a heartbeat counter periodically.
+func Heartbeat(stats Statter) {
+	HeartbeatEvery(stats, DefaultHeartbeatInterval)
+}
+
+// HeartbeatEvery enters a loop, reporting a heartbeat counter at the specified interval.
+func HeartbeatEvery(stats Statter, t time.Duration) {
+	c := time.Tick(t)
+	for range c {
+		stats.Inc("heartbeat", 1, 1.0)
+	}
+}
+
+// HeartbeatFromStatable is the same as HeartbeatEvery but from context.
+func HeartbeatFromStatable(sable Statable, t time.Duration) {
+	HeartbeatEvery(sable.Statter(), t)
+}

stats/heartbeat_test.go

@@ -0,0 +1,33 @@
+package stats_test
+
+import (
+	"testing"
+	"time"
+
+	"github.com/hamba/pkg/stats"
+	"github.com/stretchr/testify/mock"
+)
+
+func TestHeartbeat(t *testing.T) {
+	m := new(MockStats)
+	m.On("Inc", "heartbeat", int64(1), float32(1.0), mock.Anything).Return(nil)
+	stats.DefaultHeartbeatInterval = time.Millisecond
+
+	go stats.Heartbeat(m)
+
+	time.Sleep(100 * time.Millisecond)
+
+	m.AssertCalled(t, "Inc", "heartbeat", int64(1), float32(1.0), mock.Anything)
+}
+
+func TestHeartbeatFromStatable(t *testing.T) {
+	m := new(MockStats)
+	m.On("Inc", "heartbeat", int64(1), float32(1.0), mock.Anything).Return(nil)
+	sable := stats.NewMockStatable(m)
+
+	go stats.HeartbeatFromStatable(sable, time.Millisecond)
+
+	time.Sleep(100 * time.Millisecond)
+
+	m.AssertCalled(t, "Inc", "heartbeat", int64(1), float32(1.0), mock.Anything)
+}

stats/runtime_test.go

@@ -21,7 +21,7 @@ func TestRuntime(t *testing.T) {
 	m.AssertCalled(t, "Gauge", "runtime.cpu.goroutines", mock.Anything, mock.Anything, mock.Anything)
 }
 
-func TestRuntimeFromContext(t *testing.T) {
+func TestRuntimeFromStatable(t *testing.T) {
 	m := new(MockStats)
 	m.On("Gauge", mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(nil)
 	m.On("Timing", mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(nil)