forked from seaweedfs/seaweedfs
-
Notifications
You must be signed in to change notification settings - Fork 0
/
needle_map_leveldb.go
139 lines (122 loc) · 3.97 KB
/
needle_map_leveldb.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
package storage
import (
"fmt"
"os"
"path/filepath"
"github.com/joeslay/seaweedfs/weed/storage/idx"
"github.com/syndtr/goleveldb/leveldb/opt"
"github.com/joeslay/seaweedfs/weed/glog"
"github.com/joeslay/seaweedfs/weed/storage/needle_map"
. "github.com/joeslay/seaweedfs/weed/storage/types"
"github.com/joeslay/seaweedfs/weed/util"
"github.com/syndtr/goleveldb/leveldb"
)
type LevelDbNeedleMap struct {
baseNeedleMapper
dbFileName string
db *leveldb.DB
}
func NewLevelDbNeedleMap(dbFileName string, indexFile *os.File, opts *opt.Options) (m *LevelDbNeedleMap, err error) {
m = &LevelDbNeedleMap{dbFileName: dbFileName}
m.indexFile = indexFile
if !isLevelDbFresh(dbFileName, indexFile) {
glog.V(0).Infof("Start to Generate %s from %s", dbFileName, indexFile.Name())
generateLevelDbFile(dbFileName, indexFile)
glog.V(0).Infof("Finished Generating %s from %s", dbFileName, indexFile.Name())
}
glog.V(1).Infof("Opening %s...", dbFileName)
if m.db, err = leveldb.OpenFile(dbFileName, opts); err != nil {
return
}
glog.V(1).Infof("Loading %s...", indexFile.Name())
mm, indexLoadError := newNeedleMapMetricFromIndexFile(indexFile)
if indexLoadError != nil {
return nil, indexLoadError
}
m.mapMetric = *mm
return
}
func isLevelDbFresh(dbFileName string, indexFile *os.File) bool {
// normally we always write to index file first
dbLogFile, err := os.Open(filepath.Join(dbFileName, "LOG"))
if err != nil {
return false
}
defer dbLogFile.Close()
dbStat, dbStatErr := dbLogFile.Stat()
indexStat, indexStatErr := indexFile.Stat()
if dbStatErr != nil || indexStatErr != nil {
glog.V(0).Infof("Can not stat file: %v and %v", dbStatErr, indexStatErr)
return false
}
return dbStat.ModTime().After(indexStat.ModTime())
}
func generateLevelDbFile(dbFileName string, indexFile *os.File) error {
db, err := leveldb.OpenFile(dbFileName, nil)
if err != nil {
return err
}
defer db.Close()
return idx.WalkIndexFile(indexFile, func(key NeedleId, offset Offset, size uint32) error {
if !offset.IsZero() && size != TombstoneFileSize {
levelDbWrite(db, key, offset, size)
} else {
levelDbDelete(db, key)
}
return nil
})
}
func (m *LevelDbNeedleMap) Get(key NeedleId) (element *needle_map.NeedleValue, ok bool) {
bytes := make([]byte, NeedleIdSize)
NeedleIdToBytes(bytes[0:NeedleIdSize], key)
data, err := m.db.Get(bytes, nil)
if err != nil || len(data) != OffsetSize+SizeSize {
return nil, false
}
offset := BytesToOffset(data[0:OffsetSize])
size := util.BytesToUint32(data[OffsetSize : OffsetSize+SizeSize])
return &needle_map.NeedleValue{Key: key, Offset: offset, Size: size}, true
}
func (m *LevelDbNeedleMap) Put(key NeedleId, offset Offset, size uint32) error {
var oldSize uint32
if oldNeedle, ok := m.Get(key); ok {
oldSize = oldNeedle.Size
}
m.logPut(key, oldSize, size)
// write to index file first
if err := m.appendToIndexFile(key, offset, size); err != nil {
return fmt.Errorf("cannot write to indexfile %s: %v", m.indexFile.Name(), err)
}
return levelDbWrite(m.db, key, offset, size)
}
func levelDbWrite(db *leveldb.DB, key NeedleId, offset Offset, size uint32) error {
bytes := needle_map.ToBytes(key, offset, size)
if err := db.Put(bytes[0:NeedleIdSize], bytes[NeedleIdSize:NeedleIdSize+OffsetSize+SizeSize], nil); err != nil {
return fmt.Errorf("failed to write leveldb: %v", err)
}
return nil
}
func levelDbDelete(db *leveldb.DB, key NeedleId) error {
bytes := make([]byte, NeedleIdSize)
NeedleIdToBytes(bytes, key)
return db.Delete(bytes, nil)
}
func (m *LevelDbNeedleMap) Delete(key NeedleId, offset Offset) error {
if oldNeedle, ok := m.Get(key); ok {
m.logDelete(oldNeedle.Size)
}
// write to index file first
if err := m.appendToIndexFile(key, offset, TombstoneFileSize); err != nil {
return err
}
return levelDbDelete(m.db, key)
}
func (m *LevelDbNeedleMap) Close() {
m.indexFile.Close()
m.db.Close()
}
func (m *LevelDbNeedleMap) Destroy() error {
m.Close()
os.Remove(m.indexFile.Name())
return os.RemoveAll(m.dbFileName)
}