client_golang/metrics/gauge.go

63 lines
1.2 KiB
Go

/*
Copyright (c) 2012, Matt T. Proud
All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file.
*/
package metrics
import (
"fmt"
"sync"
)
/*
A gauge metric merely provides an instantaneous representation of a scalar
value or an accumulation. For instance, if one wants to expose the current
temperature or the hitherto bandwidth used, this would be the metric for such
circumstances.
*/
type GaugeMetric struct {
value float64
mutex sync.RWMutex
}
func (metric *GaugeMetric) String() string {
formatString := "[GaugeMetric; value=%f]"
metric.mutex.RLock()
defer metric.mutex.RUnlock()
return fmt.Sprintf(formatString, metric.value)
}
func (metric *GaugeMetric) Set(value float64) float64 {
metric.mutex.Lock()
defer metric.mutex.Unlock()
metric.value = value
return metric.value
}
func (metric *GaugeMetric) Get() float64 {
metric.mutex.RLock()
defer metric.mutex.RUnlock()
return metric.value
}
func (metric *GaugeMetric) Marshallable() map[string]interface{} {
metric.mutex.RLock()
defer metric.mutex.RUnlock()
v := make(map[string]interface{}, 2)
v[valueKey] = metric.value
v[typeKey] = gaugeTypeValue
return v
}