1package date
2
3// Copyright 2017 Microsoft Corporation
4//
5//  Licensed under the Apache License, Version 2.0 (the "License");
6//  you may not use this file except in compliance with the License.
7//  You may obtain a copy of the License at
8//
9//      http://www.apache.org/licenses/LICENSE-2.0
10//
11//  Unless required by applicable law or agreed to in writing, software
12//  distributed under the License is distributed on an "AS IS" BASIS,
13//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14//  See the License for the specific language governing permissions and
15//  limitations under the License.
16
17import (
18	"errors"
19	"time"
20)
21
22const (
23	rfc1123JSON = `"` + time.RFC1123 + `"`
24	rfc1123     = time.RFC1123
25)
26
27// TimeRFC1123 defines a type similar to time.Time but assumes a layout of RFC1123 date-time (i.e.,
28// Mon, 02 Jan 2006 15:04:05 MST).
29type TimeRFC1123 struct {
30	time.Time
31}
32
33// UnmarshalJSON reconstitutes the Time from a JSON string conforming to RFC1123 date-time
34// (i.e., Mon, 02 Jan 2006 15:04:05 MST).
35func (t *TimeRFC1123) UnmarshalJSON(data []byte) (err error) {
36	t.Time, err = ParseTime(rfc1123JSON, string(data))
37	if err != nil {
38		return err
39	}
40	return nil
41}
42
43// MarshalJSON preserves the Time as a JSON string conforming to RFC1123 date-time (i.e.,
44// Mon, 02 Jan 2006 15:04:05 MST).
45func (t TimeRFC1123) MarshalJSON() ([]byte, error) {
46	if y := t.Year(); y < 0 || y >= 10000 {
47		return nil, errors.New("Time.MarshalJSON: year outside of range [0,9999]")
48	}
49	b := []byte(t.Format(rfc1123JSON))
50	return b, nil
51}
52
53// MarshalText preserves the Time as a byte array conforming to RFC1123 date-time (i.e.,
54// Mon, 02 Jan 2006 15:04:05 MST).
55func (t TimeRFC1123) MarshalText() ([]byte, error) {
56	if y := t.Year(); y < 0 || y >= 10000 {
57		return nil, errors.New("Time.MarshalText: year outside of range [0,9999]")
58	}
59
60	b := []byte(t.Format(rfc1123))
61	return b, nil
62}
63
64// UnmarshalText reconstitutes a Time saved as a byte array conforming to RFC1123 date-time
65// (i.e., Mon, 02 Jan 2006 15:04:05 MST).
66func (t *TimeRFC1123) UnmarshalText(data []byte) (err error) {
67	t.Time, err = ParseTime(rfc1123, string(data))
68	if err != nil {
69		return err
70	}
71	return nil
72}
73
74// MarshalBinary preserves the Time as a byte array conforming to RFC1123 date-time (i.e.,
75// Mon, 02 Jan 2006 15:04:05 MST).
76func (t TimeRFC1123) MarshalBinary() ([]byte, error) {
77	return t.MarshalText()
78}
79
80// UnmarshalBinary reconstitutes a Time saved as a byte array conforming to RFC1123 date-time
81// (i.e., Mon, 02 Jan 2006 15:04:05 MST).
82func (t *TimeRFC1123) UnmarshalBinary(data []byte) error {
83	return t.UnmarshalText(data)
84}
85
86// ToTime returns a Time as a time.Time
87func (t TimeRFC1123) ToTime() time.Time {
88	return t.Time
89}
90
91// String returns the Time formatted as an RFC1123 date-time string (i.e.,
92// Mon, 02 Jan 2006 15:04:05 MST).
93func (t TimeRFC1123) String() string {
94	// Note: time.Time.String does not return an RFC1123 compliant string, time.Time.MarshalText does.
95	b, err := t.MarshalText()
96	if err != nil {
97		return ""
98	}
99	return string(b)
100}
101