open-nomad/vendor/github.com/docker/go-metrics/timer.go

86 lines
2.2 KiB
Go

package metrics
import (
"time"
"github.com/prometheus/client_golang/prometheus"
)
// StartTimer begins a timer observation at the callsite. When the target
// operation is completed, the caller should call the return done func().
func StartTimer(timer Timer) (done func()) {
start := time.Now()
return func() {
timer.Update(time.Since(start))
}
}
// Timer is a metric that allows collecting the duration of an action in seconds
type Timer interface {
// Update records an observation, duration, and converts to the target
// units.
Update(duration time.Duration)
// UpdateSince will add the duration from the provided starting time to the
// timer's summary with the precisions that was used in creation of the timer
UpdateSince(time.Time)
}
// LabeledTimer is a timer that must have label values populated before use.
type LabeledTimer interface {
WithValues(labels ...string) *labeledTimerObserver
}
type labeledTimer struct {
m *prometheus.HistogramVec
}
type labeledTimerObserver struct {
m prometheus.Observer
}
func (lbo *labeledTimerObserver) Update(duration time.Duration) {
lbo.m.Observe(duration.Seconds())
}
func (lbo *labeledTimerObserver) UpdateSince(since time.Time) {
lbo.m.Observe(time.Since(since).Seconds())
}
func (lt *labeledTimer) WithValues(labels ...string) *labeledTimerObserver {
return &labeledTimerObserver{m: lt.m.WithLabelValues(labels...)}
}
func (lt *labeledTimer) Describe(c chan<- *prometheus.Desc) {
lt.m.Describe(c)
}
func (lt *labeledTimer) Collect(c chan<- prometheus.Metric) {
lt.m.Collect(c)
}
type timer struct {
m prometheus.Observer
}
func (t *timer) Update(duration time.Duration) {
t.m.Observe(duration.Seconds())
}
func (t *timer) UpdateSince(since time.Time) {
t.m.Observe(time.Since(since).Seconds())
}
func (t *timer) Describe(c chan<- *prometheus.Desc) {
c <- t.m.(prometheus.Metric).Desc()
}
func (t *timer) Collect(c chan<- prometheus.Metric) {
// Are there any observers that don't implement Collector? It is really
// unclear what the point of the upstream change was, but we'll let this
// panic if we get an observer that doesn't implement collector. In this
// case, we should almost always see metricVec objects, so this should
// never panic.
t.m.(prometheus.Collector).Collect(c)
}