cloudflared-mirror/vendor/github.com/prometheus/client_golang/prometheus/timer.go

55 lines
1.7 KiB
Go

// Copyright 2016 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package prometheus
import "time"
// Timer is a helper type to time functions. Use NewTimer to create new
// instances.
type Timer struct {
begin time.Time
observer Observer
}
// NewTimer creates a new Timer. The provided Observer is used to observe a
// duration in seconds. Timer is usually used to time a function call in the
// following way:
// func TimeMe() {
// timer := NewTimer(myHistogram)
// defer timer.ObserveDuration()
// // Do actual work.
// }
func NewTimer(o Observer) *Timer {
return &Timer{
begin: time.Now(),
observer: o,
}
}
// ObserveDuration records the duration passed since the Timer was created with
// NewTimer. It calls the Observe method of the Observer provided during
// construction with the duration in seconds as an argument. The observed
// duration is also returned. ObserveDuration is usually called with a defer
// statement.
//
// Note that this method is only guaranteed to never observe negative durations
// if used with Go1.9+.
func (t *Timer) ObserveDuration() time.Duration {
d := time.Since(t.begin)
if t.observer != nil {
t.observer.Observe(d.Seconds())
}
return d
}