package librato import ( "fmt" "log" "math" "regexp" "time" "github.com/ethereum/go-ethereum/metrics" ) // a regexp for extracting the unit from time.Duration.String var unitRegexp = regexp.MustCompile(`[^\\d]+$`) // a helper that turns a time.Duration into librato display attributes for timer metrics func translateTimerAttributes(d time.Duration) (attrs map[string]interface{}) { attrs = make(map[string]interface{}) attrs[DisplayTransform] = fmt.Sprintf("x/%d", int64(d)) attrs[DisplayUnitsShort] = string(unitRegexp.Find([]byte(d.String()))) return } type Reporter struct { Email, Token string Namespace string Source string Interval time.Duration Registry metrics.Registry Percentiles []float64 // percentiles to report on histogram metrics TimerAttributes map[string]interface{} // units in which timers will be displayed intervalSec int64 } func NewReporter(r metrics.Registry, d time.Duration, e string, t string, s string, p []float64, u time.Duration) *Reporter { return &Reporter{e, t, "", s, d, r, p, translateTimerAttributes(u), int64(d / time.Second)} } func Librato(r metrics.Registry, d time.Duration, e string, t string, s string, p []float64, u time.Duration) { NewReporter(r, d, e, t, s, p, u).Run() } func (rep *Reporter) Run() { log.Printf("WARNING: This client has been DEPRECATED! It has been moved to https://github.com/mihasya/go-metrics-librato and will be removed from rcrowley/go-metrics on August 5th 2015") ticker := time.NewTicker(rep.Interval) defer ticker.Stop() metricsApi := &LibratoClient{rep.Email, rep.Token} for now := range ticker.C { var metrics Batch var err error if metrics, err = rep.BuildRequest(now, rep.Registry); err != nil { log.Printf("ERROR constructing librato request body %s", err) continue } if err := metricsApi.PostMetrics(metrics); err != nil { log.Printf("ERROR sending metrics to librato %s", err) continue } } } // calculate sum of squares from data provided by metrics.Histogram // see http://en.wikipedia.org/wiki/Standard_deviation#Rapid_calculation_methods func sumSquares(s metrics.Sample) float64 { count := float64(s.Count()) sumSquared := math.Pow(count*s.Mean(), 2) sumSquares := math.Pow(count*s.StdDev(), 2) + sumSquared/count if math.IsNaN(sumSquares) { return 0.0 } return sumSquares } func sumSquaresTimer(t metrics.Timer) float64 { count := float64(t.Count()) sumSquared := math.Pow(count*t.Mean(), 2) sumSquares := math.Pow(count*t.StdDev(), 2) + sumSquared/count if math.IsNaN(sumSquares) { return 0.0 } return sumSquares } func (rep *Reporter) BuildRequest(now time.Time, r metrics.Registry) (snapshot Batch, err error) { snapshot = Batch{ // coerce timestamps to a stepping fn so that they line up in Librato graphs MeasureTime: (now.Unix() / rep.intervalSec) * rep.intervalSec, Source: rep.Source, } snapshot.Gauges = make([]Measurement, 0) snapshot.Counters = make([]Measurement, 0) histogramGaugeCount := 1 + len(rep.Percentiles) r.Each(func(name string, metric interface{}) { if rep.Namespace != "" { name = fmt.Sprintf("%s.%s", rep.Namespace, name) } measurement := Measurement{} measurement[Period] = rep.Interval.Seconds() switch m := metric.(type) { case metrics.Counter: if m.Count() > 0 { measurement[Name] = fmt.Sprintf("%s.%s", name, "count") measurement[Value] = float64(m.Count()) measurement[Attributes] = map[string]interface{}{ DisplayUnitsLong: Operations, DisplayUnitsShort: OperationsShort, DisplayMin: "0", } snapshot.Counters = append(snapshot.Counters, measurement) } case metrics.CounterFloat64: if m.Count() > 0 { measurement[Name] = fmt.Sprintf("%s.%s", name, "count") measurement[Value] = m.Count() measurement[Attributes] = map[string]interface{}{ DisplayUnitsLong: Operations, DisplayUnitsShort: OperationsShort, DisplayMin: "0", } snapshot.Counters = append(snapshot.Counters, measurement) } case metrics.Gauge: measurement[Name] = name measurement[Value] = float64(m.Value()) snapshot.Gauges = append(snapshot.Gauges, measurement) case metrics.GaugeFloat64: measurement[Name] = name measurement[Value] = m.Value() snapshot.Gauges = append(snapshot.Gauges, measurement) case metrics.Histogram: if m.Count() > 0 { gauges := make([]Measurement, histogramGaugeCount) s := m.Sample() measurement[Name] = fmt.Sprintf("%s.%s", name, "hist") measurement[Count] = uint64(s.Count()) measurement[Max] = float64(s.Max()) measurement[Min] = float64(s.Min()) measurement[Sum] = float64(s.Sum()) measurement[SumSquares] = sumSquares(s) gauges[0] = measurement for i, p := range rep.Percentiles { gauges[i+1] = Measurement{ Name: fmt.Sprintf("%s.%.2f", measurement[Name], p), Value: s.Percentile(p), Period: measurement[Period], } } snapshot.Gauges = append(snapshot.Gauges, gauges...) } case metrics.Meter: measurement[Name] = name measurement[Value] = float64(m.Count()) snapshot.Counters = append(snapshot.Counters, measurement) snapshot.Gauges = append(snapshot.Gauges, Measurement{ Name: fmt.Sprintf("%s.%s", name, "1min"), Value: m.Rate1(), Period: int64(rep.Interval.Seconds()), Attributes: map[string]interface{}{ DisplayUnitsLong: Operations, DisplayUnitsShort: OperationsShort, DisplayMin: "0", }, }, Measurement{ Name: fmt.Sprintf("%s.%s", name, "5min"), Value: m.Rate5(), Period: int64(rep.Interval.Seconds()), Attributes: map[string]interface{}{ DisplayUnitsLong: Operations, DisplayUnitsShort: OperationsShort, DisplayMin: "0", }, }, Measurement{ Name: fmt.Sprintf("%s.%s", name, "15min"), Value: m.Rate15(), Period: int64(rep.Interval.Seconds()), Attributes: map[string]interface{}{ DisplayUnitsLong: Operations, DisplayUnitsShort: OperationsShort, DisplayMin: "0", }, }, ) case metrics.Timer: measurement[Name] = name measurement[Value] = float64(m.Count()) snapshot.Counters = append(snapshot.Counters, measurement) if m.Count() > 0 { libratoName := fmt.Sprintf("%s.%s", name, "timer.mean") gauges := make([]Measurement, histogramGaugeCount) gauges[0] = Measurement{ Name: libratoName, Count: uint64(m.Count()), Sum: m.Mean() * float64(m.Count()), Max: float64(m.Max()), Min: float64(m.Min()), SumSquares: sumSquaresTimer(m), Period: int64(rep.Interval.Seconds()), Attributes: rep.TimerAttributes, } for i, p := range rep.Percentiles { gauges[i+1] = Measurement{ Name: fmt.Sprintf("%s.timer.%2.0f", name, p*100), Value: m.Percentile(p), Period: int64(rep.Interval.Seconds()), Attributes: rep.TimerAttributes, } } snapshot.Gauges = append(snapshot.Gauges, gauges...) snapshot.Gauges = append(snapshot.Gauges, Measurement{ Name: fmt.Sprintf("%s.%s", name, "rate.1min"), Value: m.Rate1(), Period: int64(rep.Interval.Seconds()), Attributes: map[string]interface{}{ DisplayUnitsLong: Operations, DisplayUnitsShort: OperationsShort, DisplayMin: "0", }, }, Measurement{ Name: fmt.Sprintf("%s.%s", name, "rate.5min"), Value: m.Rate5(), Period: int64(rep.Interval.Seconds()), Attributes: map[string]interface{}{ DisplayUnitsLong: Operations, DisplayUnitsShort: OperationsShort, DisplayMin: "0", }, }, Measurement{ Name: fmt.Sprintf("%s.%s", name, "rate.15min"), Value: m.Rate15(), Period: int64(rep.Interval.Seconds()), Attributes: map[string]interface{}{ DisplayUnitsLong: Operations, DisplayUnitsShort: OperationsShort, DisplayMin: "0", }, }, ) } } }) return }