aboutsummaryrefslogtreecommitdiff
path: root/vendor/github.com/golang/protobuf/ptypes/timestamp.go
blob: 47f10dbc2cccefcac7dfe0bcc83d272960fbb182 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
// Go support for Protocol Buffers - Google's data interchange format
//
// Copyright 2016 The Go Authors.  All rights reserved.
// https://github.com/golang/protobuf
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

package ptypes

// This file implements operations on google.protobuf.Timestamp.

import (
	"errors"
	"fmt"
	"time"

	tspb "github.com/golang/protobuf/ptypes/timestamp"
)

const (
	// Seconds field of the earliest valid Timestamp.
	// This is time.Date(1, 1, 1, 0, 0, 0, 0, time.UTC).Unix().
	minValidSeconds = -62135596800
	// Seconds field just after the latest valid Timestamp.
	// This is time.Date(10000, 1, 1, 0, 0, 0, 0, time.UTC).Unix().
	maxValidSeconds = 253402300800
)

// validateTimestamp determines whether a Timestamp is valid.
// A valid timestamp represents a time in the range
// [0001-01-01, 10000-01-01) and has a Nanos field
// in the range [0, 1e9).
//
// If the Timestamp is valid, validateTimestamp returns nil.
// Otherwise, it returns an error that describes
// the problem.
//
// Every valid Timestamp can be represented by a time.Time, but the converse is not true.
func validateTimestamp(ts *tspb.Timestamp) error {
	if ts == nil {
		return errors.New("timestamp: nil Timestamp")
	}
	if ts.Seconds < minValidSeconds {
		return fmt.Errorf("timestamp: %v before 0001-01-01", ts)
	}
	if ts.Seconds >= maxValidSeconds {
		return fmt.Errorf("timestamp: %v after 10000-01-01", ts)
	}
	if ts.Nanos < 0 || ts.Nanos >= 1e9 {
		return fmt.Errorf("timestamp: %v: nanos not in range [0, 1e9)", ts)
	}
	return nil
}

// Timestamp converts a google.protobuf.Timestamp proto to a time.Time.
// It returns an error if the argument is invalid.
//
// Unlike most Go functions, if Timestamp returns an error, the first return value
// is not the zero time.Time. Instead, it is the value obtained from the
// time.Unix function when passed the contents of the Timestamp, in the UTC
// locale. This may or may not be a meaningful time; many invalid Timestamps
// do map to valid time.Times.
//
// A nil Timestamp returns an error. The first return value in that case is
// undefined.
func Timestamp(ts *tspb.Timestamp) (time.Time, error) {
	// Don't return the zero value on error, because corresponds to a valid
	// timestamp. Instead return whatever time.Unix gives us.
	var t time.Time
	if ts == nil {
		t = time.Unix(0, 0).UTC() // treat nil like the empty Timestamp
	} else {
		t = time.Unix(ts.Seconds, int64(ts.Nanos)).UTC()
	}
	return t, validateTimestamp(ts)
}

// TimestampNow returns a google.protobuf.Timestamp for the current time.
func TimestampNow() *tspb.Timestamp {
	ts, err := TimestampProto(time.Now())
	if err != nil {
		panic("ptypes: time.Now() out of Timestamp range")
	}
	return ts
}

// TimestampProto converts the time.Time to a google.protobuf.Timestamp proto.
// It returns an error if the resulting Timestamp is invalid.
func TimestampProto(t time.Time) (*tspb.Timestamp, error) {
	seconds := t.Unix()
	nanos := int32(t.Sub(time.Unix(seconds, 0)))
	ts := &tspb.Timestamp{
		Seconds: seconds,
		Nanos:   nanos,
	}
	if err := validateTimestamp(ts); err != nil {
		return nil, err
	}
	return ts, nil
}

// TimestampString returns the RFC 3339 string for valid Timestamps. For invalid
// Timestamps, it returns an error message in parentheses.
func TimestampString(ts *tspb.Timestamp) string {
	t, err := Timestamp(ts)
	if err != nil {
		return fmt.Sprintf("(%v)", err)
	}
	return t.Format(time.RFC3339Nano)
}