package metrics
import (
"fmt"
"io"
"sort"
"time"
)
// Write sorts writes each metric in the given registry periodically to the
// given io.Writer.
func Write(r Registry, d time.Duration, w io.Writer) {
for range time.Tick(d) {
WriteOnce(r, w)
}
}
// WriteOnce sorts and writes metrics in the given registry to the given
// io.Writer.
func WriteOnce(r Registry, w io.Writer) {
var namedMetrics namedMetricSlice
r.Each(func(name string, i interface{}) {
namedMetrics = append(namedMetrics, namedMetric{name, i})
})
sort.Sort(namedMetrics)
for _, namedMetric := range namedMetrics {
switch metric := namedMetric.m.(type) {
case Counter:
fmt.Fprintf(w, "counter %s\n", namedMetric.name)
fmt.Fprintf(w, " count: %9d\n", metric.Count())
case Gauge:
fmt.Fprintf(w, "gauge %s\n", namedMetric.name)
fmt.Fprintf(w, " value: %9d\n", metric.Value())
case GaugeFloat64:
fmt.Fprintf(w, "gauge %s\n", namedMetric.name)
fmt.Fprintf(w, " value: %f\n", metric.Value())
case Healthcheck:
metric.Check()
fmt.Fprintf(w, "healthcheck %s\n", namedMetric.name)
fmt.Fprintf(w, " error: %v\n", metric.Error())
case Histogram:
h := metric.Snapshot()
ps := h.Percentiles([]float64{0.5, 0.75, 0.95, 0.99, 0.999})
fmt.Fprintf(w, "histogram %s\n", namedMetric.name)
fmt.Fprintf(w, " count: %9d\n", h.Count())
fmt.Fprintf(w, " min: %9d\n", h.Min())
fmt.Fprintf(w, " max: %9d\n", h.Max())
fmt.Fprintf(w, " mean: %12.2f\n", h.Mean())
fmt.Fprintf(w, " stddev: %12.2f\n", h.StdDev())
fmt.Fprintf(w, " median: %12.2f\n", ps[0])
fmt.Fprintf(w, " 75%%: %12.2f\n", ps[1])
fmt.Fprintf(w, " 95%%: %12.2f\n", ps[2])
fmt.Fprintf(w, " 99%%: %12.2f\n", ps[3])
fmt.Fprintf(w, " 99.9%%: %12.2f\n", ps[4])
case Meter:
m := metric.Snapshot()
fmt.Fprintf(w, "meter %s\n", namedMetric.name)
fmt.Fprintf(w, " count: %9d\n", m.Count())
fmt.Fprintf(w, " 1-min rate: %12.2f\n", m.Rate1())
fmt.Fprintf(w, " 5-min rate: %12.2f\n", m.Rate5())
fmt.Fprintf(w, " 15-min rate: %12.2f\n", m.Rate15())
fmt.Fprintf(w, " mean rate: %12.2f\n", m.RateMean())
case Timer:
t := metric.Snapshot()
ps := t.Percentiles([]float64{0.5, 0.75, 0.95, 0.99, 0.999})
fmt.Fprintf(w, "timer %s\n", namedMetric.name)
fmt.Fprintf(w, " count: %9d\n", t.Count())
fmt.Fprintf(w, " min: %9d\n", t.Min())
fmt.Fprintf(w, " max: %9d\n", t.Max())
fmt.Fprintf(w, " mean: %12.2f\n", t.Mean())
fmt.Fprintf(w, " stddev: %12.2f\n", t.StdDev())
fmt.Fprintf(w, " median: %12.2f\n", ps[0])
fmt.Fprintf(w, " 75%%: %12.2f\n", ps[1])
fmt.Fprintf(w, " 95%%: %12.2f\n", ps[2])
fmt.Fprintf(w, " 99%%: %12.2f\n", ps[3])
fmt.Fprintf(w, " 99.9%%: %12.2f\n", ps[4])
fmt.Fprintf(w, " 1-min rate: %12.2f\n", t.Rate1())
fmt.Fprintf(w, " 5-min rate: %12.2f\n", t.Rate5())
fmt.Fprintf(w, " 15-min rate: %12.2f\n", t.Rate15())
fmt.Fprintf(w, " mean rate: %12.2f\n", t.RateMean())
}
}
}
type namedMetric struct {
name string
m interface{}
}
// namedMetricSlice is a slice of namedMetrics that implements sort.Interface.
type namedMetricSlice []namedMetric
func (nms namedMetricSlice) Len() int { return len(nms) }
func (nms namedMetricSlice) Swap(i, j int) { nms[i], nms[j] = nms[j], nms[i] }
func (nms namedMetricSlice) Less(i, j int) bool {
return nms[i].name < nms[j].name
}
