VictoriaMetrics/lib/flagutil/duration.go

82 lines
2.1 KiB
Go

package flagutil
import (
"flag"
"fmt"
"strconv"
"strings"
"time"
"github.com/VictoriaMetrics/metricsql"
)
// NewDuration returns new `duration` flag with the given name, defaultValue and description.
//
// DefaultValue is in months.
func NewDuration(name string, defaultValue string, description string) *Duration {
description += "\nThe following optional suffixes are supported: s (second), m (minute), h (hour), d (day), w (week), y (year). " +
"If suffix isn't set, then the duration is counted in months"
d := &Duration{}
if err := d.Set(defaultValue); err != nil {
panic(fmt.Sprintf("BUG: can not parse default value %s for flag %s", defaultValue, name))
}
flag.Var(d, name, description)
return d
}
// Duration is a flag for holding duration.
type Duration struct {
// msecs contains parsed duration in milliseconds.
msecs int64
valueString string
}
// Duration returns d as time.Duration
func (d *Duration) Duration() time.Duration {
return time.Millisecond * time.Duration(d.msecs)
}
// Milliseconds returns d in milliseconds
func (d *Duration) Milliseconds() int64 {
return d.msecs
}
// String implements flag.Value interface
func (d *Duration) String() string {
return d.valueString
}
// Set implements flag.Value interface
func (d *Duration) Set(value string) error {
// An attempt to parse value in months.
months, err := strconv.ParseFloat(value, 64)
if err == nil {
if months > maxMonths {
return fmt.Errorf("duration months must be smaller than %d; got %g", maxMonths, months)
}
if months < 0 {
return fmt.Errorf("duration months cannot be negative; got %g", months)
}
d.msecs = int64(months * msecsPer31Days)
d.valueString = value
return nil
}
// Parse duration.
value = strings.ToLower(value)
if strings.HasSuffix(value, "m") {
return fmt.Errorf("duration in months must be set without `m` suffix due to ambiguity with duration in minutes; got %s", value)
}
msecs, err := metricsql.PositiveDurationValue(value, 0)
if err != nil {
return err
}
d.msecs = msecs
d.valueString = value
return nil
}
const maxMonths = 12 * 100
const msecsPer31Days = 31 * 24 * 3600 * 1000