Fixed FGaugeDelta with negative value not to send a 0 value first (it…

… mistakenly had the same implementation of FGauge)

README.md

@@ -72,7 +72,8 @@ The string `%HOST%` in the metric name will automatically be replaced with the h
 
  * Added stdout client ("echo" service for debugging)
  * Fixed [issue #23](https:/quipo/statsd/issues/23): GaugeDelta event Stats() should not send an absolute value of 0
- * Fixed FGauge to only preserve the last value in the batch (it mistakenly had the same implementation of FGaugeDelta)
+ * Fixed FGauge's collation in the buffered client to only preserve the last value in the batch (it mistakenly had the same implementation of FGaugeDelta's collation)
+ * Fixed FGaugeDelta with negative value not to send a 0 value first (it mistakenly had the same implementation of FGauge)
  * Added tests and compile-time checks that the default events implement the Event interface
 
 * `v.1.2.0`: Sample rate support (thanks to [Hongjian Zhu](https:/hongjianzhu))

bufferedclient_test.go

@@ -276,7 +276,6 @@ func TestBufferedFloat64(t *testing.T) {
  },
  expected: KVfloat64Sorter{
  {"a:b:c", 3.0},
- {"d:e:f", 0},
  {"d:e:f", -2.2},
  {"g.h.i", +1.3},
  {"zz." + hostname, 1.4}, // also test %HOST% replacement

event/fgauge_test.go

@@ -24,3 +24,18 @@ func TestFGaugeUpdate(t *testing.T) {
  t.Errorf("did not receive all metrics: Expected: %T %v, Actual: %T %v ", expected, expected, actual, actual)
  }
 }
+
+func TestFGaugeUpdateNegative(t *testing.T) {
+ e1 := &FGauge{Name: "test", Value: float64(-10.1)}
+ e2 := &FGauge{Name: "test", Value: float64(-3.4)}
+ err := e1.Update(e2)
+ if nil != err {
+ t.Error(err)
+ }
+
+ expected := []string{"test:0|g", "test:-3.4|g"} // only the last value is flushed
+ actual := e1.Stats()
+ if !reflect.DeepEqual(expected, actual) {
+ t.Errorf("did not receive all metrics: Expected: %T %v, Actual: %T %v ", expected, expected, actual, actual)
+ }
+}

event/fgaugedelta.go

@@ -26,16 +26,7 @@ func (e FGaugeDelta) Payload() interface{} {
 
 // Stats returns an array of StatsD events as they travel over UDP
 func (e FGaugeDelta) Stats() []string {
- if e.Value < 0 {
- // because a leading '+' or '-' in the value of a gauge denotes a delta, to send
- // a negative gauge value we first set the gauge absolutely to 0, then send the
- // negative value as a delta from 0 (that's just how the spec works :-)
- return []string{
- fmt.Sprintf("%s:%d|g", e.Name, 0),
- fmt.Sprintf("%s:%g|g", e.Name, e.Value),
- }
- }
- return []string{fmt.Sprintf("%s:%g|g", e.Name, e.Value)}
+ return []string{fmt.Sprintf("%s:%+g|g", e.Name, e.Value)}
 }
 
 // Key returns the name of this metric

event/fgaugedelta_test.go

@@ -18,7 +18,27 @@ func TestFGaugeDeltaUpdate(t *testing.T) {
  t.Error(err)
  }
 
- expected := []string{"test:20.2|g"}
+ expected := []string{"test:+20.2|g"}
+ actual := e1.Stats()
+ if !reflect.DeepEqual(expected, actual) {
+ t.Errorf("did not receive all metrics: Expected: %T %v, Actual: %T %v ", expected, expected, actual, actual)
+ }
+}
+
+func TestFGaugeDeltaUpdateNegative(t *testing.T) {
+ e1 := &FGaugeDelta{Name: "test", Value: float64(-15.1)}
+ e2 := &FGaugeDelta{Name: "test", Value: float64(10.0)}
+ e3 := &FGaugeDelta{Name: "test", Value: float64(-15.1)}
+ err := e1.Update(e2)
+ if nil != err {
+ t.Error(err)
+ }
+ err = e1.Update(e3)
+ if nil != err {
+ t.Error(err)
+ }
+
+ expected := []string{"test:-20.2|g"}
  actual := e1.Stats()
  if !reflect.DeepEqual(expected, actual) {
  t.Errorf("did not receive all metrics: Expected: %T %v, Actual: %T %v ", expected, expected, actual, actual)

event/gauge_test.go

@@ -24,3 +24,18 @@ func TestGaugeUpdate(t *testing.T) {
  t.Errorf("did not receive all metrics: Expected: %T %v, Actual: %T %v ", expected, expected, actual, actual)
  }
 }
+
+func TestGaugeUpdateNegative(t *testing.T) {
+ e1 := &Gauge{Name: "test", Value: int64(-10)}
+ e2 := &Gauge{Name: "test", Value: int64(-3)}
+ err := e1.Update(e2)
+ if nil != err {
+ t.Error(err)
+ }
+
+ expected := []string{"test:0|g", "test:-3|g"} // only the last value is flushed
+ actual := e1.Stats()
+ if !reflect.DeepEqual(expected, actual) {
+ t.Errorf("did not receive all metrics: Expected: %T %v, Actual: %T %v ", expected, expected, actual, actual)
+ }
+}

event/gaugedelta.go

@@ -26,10 +26,7 @@ func (e GaugeDelta) Payload() interface{} {
 
 // Stats returns an array of StatsD events as they travel over UDP
 func (e GaugeDelta) Stats() []string {
- if e.Value < 0 {
- return []string{fmt.Sprintf("%s:%+d|g", e.Name, e.Value)}
- }
- return []string{fmt.Sprintf("%s:+%d|g", e.Name, e.Value)}
+ return []string{fmt.Sprintf("%s:%+d|g", e.Name, e.Value)}
 }
 
 // Key returns the name of this metric

event/gaugedelta_test.go

@@ -24,3 +24,23 @@ func TestGaugeDeltaUpdate(t *testing.T) {
  t.Errorf("did not receive all metrics: Expected: %T %v, Actual: %T %v ", expected, expected, actual, actual)
  }
 }
+
+func TestGaugeDeltaUpdateNegative(t *testing.T) {
+ e1 := &GaugeDelta{Name: "test", Value: int64(-15)}
+ e2 := &GaugeDelta{Name: "test", Value: int64(10)}
+ e3 := &GaugeDelta{Name: "test", Value: int64(-15)}
+ err := e1.Update(e2)
+ if nil != err {
+ t.Error(err)
+ }
+ err = e1.Update(e3)
+ if nil != err {
+ t.Error(err)
+ }
+
+ expected := []string{"test:-20|g"}
+ actual := e1.Stats()
+ if !reflect.DeepEqual(expected, actual) {
+ t.Errorf("did not receive all metrics: Expected: %T %v, Actual: %T %v ", expected, expected, actual, actual)
+ }
+}