util/time/duration.go

@@ -1,6 +1,7 @@
 package time
 
 import (
+	"encoding/json"
 	"fmt"
 	"time"
 )
@@ -46,3 +47,36 @@ func ParseDuration(s string) (time.Duration, error) {
 
 	return td, err
 }
+
+func (d Duration) MarshalJSON() ([]byte, error) {
+	return json.Marshal(time.Duration(d).String())
+}
+
+func (d *Duration) UnmarshalJSON(b []byte) error {
+	var v interface{}
+	if err := json.Unmarshal(b, &v); err != nil {
+		return err
+	}
+	switch value := v.(type) {
+	case float64:
+		*d = Duration(time.Duration(value))
+		return nil
+	case string:
+		dv, err := time.ParseDuration(value)
+		if err != nil {
+			return err
+		}
+		*d = Duration(dv)
+		return nil
+	default:
+		return fmt.Errorf("invalid duration")
+	}
+}
+
+/*
+func (d Duration) MarshalYAML() (interface{}, error) {
+	return nil, nil
+}
+
+func (d Duration)
+*/

util/time/duration_test.go

@@ -1,10 +1,37 @@
 package time
 
 import (
+	"bytes"
+	"encoding/json"
 	"testing"
 	"time"
 )
 
+func TestMarshalJSON(t *testing.T) {
+	d := Duration(10000000)
+	buf, err := json.Marshal(d)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(buf, []byte(`"10ms"`)) {
+		t.Fatalf("invalid duration: %s != %s", buf, `"10ms"`)
+	}
+}
+
+func TestUnmarshalJSON(t *testing.T) {
+	type str struct {
+		TTL Duration `json:"ttl"`
+	}
+	v := &str{}
+
+	err := json.Unmarshal([]byte(`{"ttl":"10ms"}`), v)
+	if err != nil {
+		t.Fatal(err)
+	} else if v.TTL != 10000000 {
+		t.Fatalf("invalid duration %v != 10000000", v.TTL)
+	}
+}
+
 func TestParseDuration(t *testing.T) {
 	var td time.Duration
 	var err error