khenaidoo | ac63710 | 2019-01-14 15:44:34 -0500 | [diff] [blame] | 1 | // Go support for Protocol Buffers - Google's data interchange format |
| 2 | // |
| 3 | // Copyright 2016 The Go Authors. All rights reserved. |
| 4 | // https://github.com/golang/protobuf |
| 5 | // |
| 6 | // Redistribution and use in source and binary forms, with or without |
| 7 | // modification, are permitted provided that the following conditions are |
| 8 | // met: |
| 9 | // |
| 10 | // * Redistributions of source code must retain the above copyright |
| 11 | // notice, this list of conditions and the following disclaimer. |
| 12 | // * Redistributions in binary form must reproduce the above |
| 13 | // copyright notice, this list of conditions and the following disclaimer |
| 14 | // in the documentation and/or other materials provided with the |
| 15 | // distribution. |
| 16 | // * Neither the name of Google Inc. nor the names of its |
| 17 | // contributors may be used to endorse or promote products derived from |
| 18 | // this software without specific prior written permission. |
| 19 | // |
| 20 | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 21 | // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 22 | // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 23 | // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| 24 | // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 25 | // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 26 | // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 27 | // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 28 | // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 29 | // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 30 | // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 31 | |
| 32 | package ptypes |
| 33 | |
| 34 | // This file implements operations on google.protobuf.Timestamp. |
| 35 | |
| 36 | import ( |
| 37 | "errors" |
| 38 | "fmt" |
| 39 | "time" |
| 40 | |
| 41 | tspb "github.com/golang/protobuf/ptypes/timestamp" |
| 42 | ) |
| 43 | |
| 44 | const ( |
| 45 | // Seconds field of the earliest valid Timestamp. |
| 46 | // This is time.Date(1, 1, 1, 0, 0, 0, 0, time.UTC).Unix(). |
| 47 | minValidSeconds = -62135596800 |
| 48 | // Seconds field just after the latest valid Timestamp. |
| 49 | // This is time.Date(10000, 1, 1, 0, 0, 0, 0, time.UTC).Unix(). |
| 50 | maxValidSeconds = 253402300800 |
| 51 | ) |
| 52 | |
| 53 | // validateTimestamp determines whether a Timestamp is valid. |
| 54 | // A valid timestamp represents a time in the range |
| 55 | // [0001-01-01, 10000-01-01) and has a Nanos field |
| 56 | // in the range [0, 1e9). |
| 57 | // |
| 58 | // If the Timestamp is valid, validateTimestamp returns nil. |
| 59 | // Otherwise, it returns an error that describes |
| 60 | // the problem. |
| 61 | // |
| 62 | // Every valid Timestamp can be represented by a time.Time, but the converse is not true. |
| 63 | func validateTimestamp(ts *tspb.Timestamp) error { |
| 64 | if ts == nil { |
| 65 | return errors.New("timestamp: nil Timestamp") |
| 66 | } |
| 67 | if ts.Seconds < minValidSeconds { |
| 68 | return fmt.Errorf("timestamp: %v before 0001-01-01", ts) |
| 69 | } |
| 70 | if ts.Seconds >= maxValidSeconds { |
| 71 | return fmt.Errorf("timestamp: %v after 10000-01-01", ts) |
| 72 | } |
| 73 | if ts.Nanos < 0 || ts.Nanos >= 1e9 { |
| 74 | return fmt.Errorf("timestamp: %v: nanos not in range [0, 1e9)", ts) |
| 75 | } |
| 76 | return nil |
| 77 | } |
| 78 | |
| 79 | // Timestamp converts a google.protobuf.Timestamp proto to a time.Time. |
| 80 | // It returns an error if the argument is invalid. |
| 81 | // |
| 82 | // Unlike most Go functions, if Timestamp returns an error, the first return value |
| 83 | // is not the zero time.Time. Instead, it is the value obtained from the |
| 84 | // time.Unix function when passed the contents of the Timestamp, in the UTC |
| 85 | // locale. This may or may not be a meaningful time; many invalid Timestamps |
| 86 | // do map to valid time.Times. |
| 87 | // |
| 88 | // A nil Timestamp returns an error. The first return value in that case is |
| 89 | // undefined. |
| 90 | func Timestamp(ts *tspb.Timestamp) (time.Time, error) { |
| 91 | // Don't return the zero value on error, because corresponds to a valid |
| 92 | // timestamp. Instead return whatever time.Unix gives us. |
| 93 | var t time.Time |
| 94 | if ts == nil { |
| 95 | t = time.Unix(0, 0).UTC() // treat nil like the empty Timestamp |
| 96 | } else { |
| 97 | t = time.Unix(ts.Seconds, int64(ts.Nanos)).UTC() |
| 98 | } |
| 99 | return t, validateTimestamp(ts) |
| 100 | } |
| 101 | |
| 102 | // TimestampNow returns a google.protobuf.Timestamp for the current time. |
| 103 | func TimestampNow() *tspb.Timestamp { |
| 104 | ts, err := TimestampProto(time.Now()) |
| 105 | if err != nil { |
| 106 | panic("ptypes: time.Now() out of Timestamp range") |
| 107 | } |
| 108 | return ts |
| 109 | } |
| 110 | |
| 111 | // TimestampProto converts the time.Time to a google.protobuf.Timestamp proto. |
| 112 | // It returns an error if the resulting Timestamp is invalid. |
| 113 | func TimestampProto(t time.Time) (*tspb.Timestamp, error) { |
| 114 | seconds := t.Unix() |
| 115 | nanos := int32(t.Sub(time.Unix(seconds, 0))) |
| 116 | ts := &tspb.Timestamp{ |
| 117 | Seconds: seconds, |
| 118 | Nanos: nanos, |
| 119 | } |
| 120 | if err := validateTimestamp(ts); err != nil { |
| 121 | return nil, err |
| 122 | } |
| 123 | return ts, nil |
| 124 | } |
| 125 | |
| 126 | // TimestampString returns the RFC 3339 string for valid Timestamps. For invalid |
| 127 | // Timestamps, it returns an error message in parentheses. |
| 128 | func TimestampString(ts *tspb.Timestamp) string { |
| 129 | t, err := Timestamp(ts) |
| 130 | if err != nil { |
| 131 | return fmt.Sprintf("(%v)", err) |
| 132 | } |
| 133 | return t.Format(time.RFC3339Nano) |
| 134 | } |