boulder/config/duration.go

70 lines
1.9 KiB
Go

package config
import (
"encoding/json"
"errors"
"reflect"
"time"
)
// Duration is custom type embedding a time.Duration which allows defining
// methods such as serialization to YAML or JSON.
type Duration struct {
time.Duration `validate:"required"`
}
// DurationCustomTypeFunc enables registration of our custom config.Duration
// type as a time.Duration and performing validation on the configured value
// using the standard suite of validation functions.
func DurationCustomTypeFunc(field reflect.Value) interface{} {
if c, ok := field.Interface().(Duration); ok {
return c.Duration
}
return reflect.Invalid
}
// ErrDurationMustBeString is returned when a non-string value is
// presented to be deserialized as a ConfigDuration
var ErrDurationMustBeString = errors.New("cannot JSON unmarshal something other than a string into a ConfigDuration")
// UnmarshalJSON parses a string into a ConfigDuration using
// time.ParseDuration. If the input does not unmarshal as a
// string, then UnmarshalJSON returns ErrDurationMustBeString.
func (d *Duration) UnmarshalJSON(b []byte) error {
s := ""
err := json.Unmarshal(b, &s)
if err != nil {
var jsonUnmarshalTypeErr *json.UnmarshalTypeError
if errors.As(err, &jsonUnmarshalTypeErr) {
return ErrDurationMustBeString
}
return err
}
dd, err := time.ParseDuration(s)
d.Duration = dd
return err
}
// MarshalJSON returns the string form of the duration, as a byte array.
func (d Duration) MarshalJSON() ([]byte, error) {
return []byte(d.Duration.String()), nil
}
// UnmarshalYAML uses the same format as JSON, but is called by the YAML
// parser (vs. the JSON parser).
func (d *Duration) UnmarshalYAML(unmarshal func(interface{}) error) error {
var s string
err := unmarshal(&s)
if err != nil {
return err
}
dur, err := time.ParseDuration(s)
if err != nil {
return err
}
d.Duration = dur
return nil
}