binding: support unix time

ref:#1979

binding/form_mapping.go

@@ -266,6 +266,26 @@ func setTimeField(val string, structField reflect.StructField, value reflect.Val
 		timeFormat = time.RFC3339
 	}
 
+	var t time.Time
+
+	switch tf := strings.ToLower(timeFormat); tf {
+	case "unix", "unixnano":
+		tv, err := strconv.ParseInt(val, 10, 0)
+		if err != nil {
+			return err
+		}
+
+		d := time.Duration(1)
+		if tf == "unixnano" {
+			d = time.Second
+		}
+
+		t = time.Unix(tv/int64(d), tv%int64(d))
+		value.Set(reflect.ValueOf(t))
+		return nil
+
+	}
+
 	if val == "" {
 		value.Set(reflect.ValueOf(time.Time{}))
 		return nil