/
id.go
206 lines (159 loc) · 4.71 KB
/
id.go
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
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
package did
import (
"encoding/base64"
"encoding/binary"
"errors"
"fmt"
"strconv"
)
const encodeBase32Map = "ybndrfg8ejkmcpqxot1uwisza345h769"
var decodeBase32Map [256]byte
const encodeBase58Map = "123456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ"
var decodeBase58Map [256]byte
// A JSONSyntaxError is returned from UnmarshalJSON if an invalid ID is provided.
type JSONSyntaxError struct{ original []byte }
func (j JSONSyntaxError) Error() string {
return fmt.Sprintf("invalid snowflake ID %q", string(j.original))
}
// ErrInvalidBase58 is returned by ParseBase58 when given an invalid []byte
var ErrInvalidBase58 = errors.New("invalid base58")
// ErrInvalidBase32 is returned by ParseBase32 when given an invalid []byte
var ErrInvalidBase32 = errors.New("invalid base32")
// Create maps for decoding Base58/Base32.
// This speeds up the process tremendously.
func init() {
for i := 0; i < len(encodeBase58Map); i++ {
decodeBase58Map[i] = 0xFF
}
for i := 0; i < len(encodeBase58Map); i++ {
decodeBase58Map[encodeBase58Map[i]] = byte(i)
}
for i := 0; i < len(encodeBase32Map); i++ {
decodeBase32Map[i] = 0xFF
}
for i := 0; i < len(encodeBase32Map); i++ {
decodeBase32Map[encodeBase32Map[i]] = byte(i)
}
}
// An ID is a custom type used for a generated ID. This is used so we can
// attach methods onto the ID.
type ID int64
// String returns a string of the snowflake ID
func (f ID) String() string {
return strconv.FormatInt(int64(f), 10)
}
// ParseString converts a string into a snowflake ID
func ParseString(id string) (ID, error) {
i, err := strconv.ParseInt(id, 10, 64)
return ID(i), err
}
// Base2 returns a string base2 of the snowflake ID
func (f ID) Base2() string {
return strconv.FormatInt(int64(f), 2)
}
// ParseBase2 converts a Base2 string into a snowflake ID
func ParseBase2(id string) (ID, error) {
i, err := strconv.ParseInt(id, 2, 64)
return ID(i), err
}
// Base32 uses the z-base-32 character set but encodes and decodes similar
// to base58, allowing it to create an even smaller result string.
// NOTE: There are many different base32 implementations so becareful when
// doing any interoperation.
func (f ID) Base32() string {
if f < 32 {
return string(encodeBase32Map[f])
}
b := make([]byte, 0, 12)
for f >= 32 {
b = append(b, encodeBase32Map[f%32])
f /= 32
}
b = append(b, encodeBase32Map[f])
for x, y := 0, len(b)-1; x < y; x, y = x+1, y-1 {
b[x], b[y] = b[y], b[x]
}
return string(b)
}
// ParseBase32 parses a base32 []byte into a snowflake ID
// NOTE: There are many different base32 implementations so becareful when
// doing any interoperation.
func ParseBase32(b []byte) (ID, error) {
var id int64
for i := range b {
if decodeBase32Map[b[i]] == 0xFF {
return -1, ErrInvalidBase32
}
id = id*32 + int64(decodeBase32Map[b[i]])
}
return ID(id), nil
}
// Base36 returns a base36 string of the snowflake ID
func (f ID) Base36() string {
return strconv.FormatInt(int64(f), 36)
}
// ParseBase36 converts a Base36 string into a snowflake ID
func ParseBase36(id string) (ID, error) {
i, err := strconv.ParseInt(id, 36, 64)
return ID(i), err
}
// Base58 returns a base58 string of the snowflake ID
func (f ID) Base58() string {
if f < 58 {
return string(encodeBase58Map[f])
}
b := make([]byte, 0, 11)
for f >= 58 {
b = append(b, encodeBase58Map[f%58])
f /= 58
}
b = append(b, encodeBase58Map[f])
for x, y := 0, len(b)-1; x < y; x, y = x+1, y-1 {
b[x], b[y] = b[y], b[x]
}
return string(b)
}
// ParseBase58 parses a base58 []byte into a snowflake ID
func ParseBase58(b []byte) (ID, error) {
var id int64
for i := range b {
if decodeBase58Map[b[i]] == 0xFF {
return -1, ErrInvalidBase58
}
id = id*58 + int64(decodeBase58Map[b[i]])
}
return ID(id), nil
}
// Base64 returns a base64 string of the snowflake ID
func (f ID) Base64() string {
return base64.StdEncoding.EncodeToString(f.Bytes())
}
// ParseBase64 converts a base64 string into a snowflake ID
func ParseBase64(id string) (ID, error) {
b, err := base64.StdEncoding.DecodeString(id)
if err != nil {
return -1, err
}
return ParseBytes(b)
}
// Bytes returns a byte slice of the snowflake ID
func (f ID) Bytes() []byte {
return []byte(f.String())
}
// ParseBytes converts a byte slice into a snowflake ID
func ParseBytes(id []byte) (ID, error) {
i, err := strconv.ParseInt(string(id), 10, 64)
return ID(i), err
}
// IntBytes returns an array of bytes of the snowflake ID, encoded as a
// big endian integer.
func (f ID) IntBytes() [8]byte {
var b [8]byte
binary.BigEndian.PutUint64(b[:], uint64(f))
return b
}
// ParseIntBytes converts an array of bytes encoded as big endian integer as
// a snowflake ID
func ParseIntBytes(id [8]byte) ID {
return ID(int64(binary.BigEndian.Uint64(id[:])))
}