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-rw-r--r--vendor/github.com/prometheus/client_golang/prometheus/timer.go74
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diff --git a/vendor/github.com/prometheus/client_golang/prometheus/timer.go b/vendor/github.com/prometheus/client_golang/prometheus/timer.go
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+// 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"
+
+// Observer is the interface that wraps the Observe method, which is used by
+// Histogram and Summary to add observations.
+type Observer interface {
+ Observe(float64)
+}
+
+// The ObserverFunc type is an adapter to allow the use of ordinary
+// functions as Observers. If f is a function with the appropriate
+// signature, ObserverFunc(f) is an Observer that calls f.
+//
+// This adapter is usually used in connection with the Timer type, and there are
+// two general use cases:
+//
+// The most common one is to use a Gauge as the Observer for a Timer.
+// See the "Gauge" Timer example.
+//
+// The more advanced use case is to create a function that dynamically decides
+// which Observer to use for observing the duration. See the "Complex" Timer
+// example.
+type ObserverFunc func(float64)
+
+// Observe calls f(value). It implements Observer.
+func (f ObserverFunc) Observe(value float64) {
+ f(value)
+}
+
+// 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. ObserveDuration is
+// usually called with a defer statement.
+func (t *Timer) ObserveDuration() {
+ if t.observer != nil {
+ t.observer.Observe(time.Since(t.begin).Seconds())
+ }
+}