/
indexer.go
217 lines (189 loc) · 4.16 KB
/
indexer.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
207
208
209
210
211
212
213
214
215
216
217
package slacklog
import (
"bufio"
"encoding/binary"
"fmt"
"os"
"path/filepath"
"strconv"
"strings"
"unicode/utf16"
)
const gramN = 2
type Indexer struct {
s *LogStore
gramIndex messageIndex
channelNumbers map[int]Channel
}
func NewIndexer(s *LogStore) *Indexer {
return &Indexer{
s: s,
gramIndex: messageIndex{},
channelNumbers: map[int]Channel{},
}
}
func (idx *Indexer) Build() error {
channelNumber := 0
for _, c := range idx.s.GetChannels() {
channelNumber++
idx.channelNumbers[channelNumber] = c
msgs, err := idx.s.GetAllMessages(c.ID)
if err != nil {
return err
}
for _, m := range msgs {
runes := []rune(m.Text)
textLen := len(runes)
for i := range runes {
for n := 1; n <= gramN; n++ {
if textLen <= i+n-1 {
break
}
key := string(runes[i : i+n])
idx.gramIndex.Add(key, channelNumber, m, i)
}
}
}
}
return nil
}
func (idx *Indexer) Output(outDir string) error {
channelFilepath := filepath.Join(outDir, "channel")
err := idx.writeChannelFile(channelFilepath, idx.channelNumbers)
if err != nil {
return err
}
for key, mPositions := range idx.gramIndex {
s := outDir
for _, u := range utf16.Encode([]rune(key)) {
s = filepath.Join(s, fmt.Sprintf("%02x", u>>8), fmt.Sprintf("%02x", u&0xff))
}
err := idx.writeIndexFile(s+".index", mPositions)
if err != nil {
return err
}
}
return nil
}
func (idx *Indexer) writeChannelFile(path string, channelNumbers map[int]Channel) error {
err := os.MkdirAll(filepath.Dir(path), 0o777)
if err != nil {
return err
}
f, err := os.Create(path)
if err != nil {
return err
}
defer f.Close()
fw := bufio.NewWriter(f)
for channelNumber, channel := range channelNumbers {
_, err := fw.Write([]byte(fmt.Sprintf("%d\t%s\t%s\n", channelNumber, channel.ID, channel.Name)))
if err != nil {
return err
}
}
err = fw.Flush()
if err != nil {
return err
}
return nil
}
func (idx *Indexer) writeIndexFile(path string, mPositions messagePositions) error {
err := os.MkdirAll(filepath.Dir(path), 0o777)
if err != nil {
return err
}
f, err := os.Create(path)
if err != nil {
return err
}
defer f.Close()
fw := bufio.NewWriter(f)
for channelNumber, mposMap := range mPositions {
_, err := fw.Write(vintBytes(channelNumber))
if err != nil {
return err
}
_, err = fw.Write(vintBytes(len(mposMap)))
if err != nil {
return err
}
for ts, positions := range mposMap {
tsParts := strings.SplitN(ts, ".", 2)
if len(tsParts) != 2 {
channel := idx.channelNumbers[channelNumber]
return fmt.Errorf("Invalid timestamp %s (%s)", ts, channel.ID)
}
tsSec, err := strconv.Atoi(tsParts[0])
if err != nil {
return err
}
err = binary.Write(fw, binary.BigEndian, uint32(tsSec))
if err != nil {
return err
}
tsMicrosec, err := strconv.Atoi(tsParts[1])
if err != nil {
return err
}
_, err = fw.Write(vintBytes(tsMicrosec))
if err != nil {
return err
}
if len(positions) == 0 {
channel := idx.channelNumbers[channelNumber]
return fmt.Errorf("Empty positions: %s: %s: %s", path, channel.ID, ts)
}
for _, pos := range positions {
_, err = fw.Write(vintBytes(pos + 1))
if err != nil {
return err
}
}
err = fw.WriteByte(0)
if err != nil {
return err
}
}
}
err = fw.Flush()
if err != nil {
return err
}
return nil
}
type messageIndex map[string]messagePositions
func (mi messageIndex) Add(key string, channelNumber int, mes *Message, pos int) {
mp, ok := mi[key]
if !ok {
mp = messagePositions{}
mi[key] = mp
}
mp.Add(channelNumber, mes, pos)
}
type messagePositions map[int]map[string][]int
func (mp messagePositions) Add(channelNumber int, mes *Message, pos int) {
mposMap, ok := mp[channelNumber]
if !ok {
mposMap = map[string][]int{}
mp[channelNumber] = mposMap
}
mposMap[mes.Timestamp] = append(mposMap[mes.Timestamp], pos)
}
func vintBytes(n int) []byte {
if n == 0 {
return []byte{0}
}
bytes := []byte{}
cont := false
for n != 0 {
b := byte(n & 0b01111111)
if cont {
b |= 0b10000000
}
bytes = append([]byte{b}, bytes...)
n >>= 7
cont = true
}
return bytes
}