/
boltmobiledemo.go
92 lines (81 loc) · 1.41 KB
/
boltmobiledemo.go
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package boltmobiledemo
import (
"bytes"
"encoding/binary"
"github.com/boltdb/bolt"
"log"
)
var (
demoBucket = []byte("demoBucket")
demoKey = []byte("demoKey")
)
func NewBoltDB(filename string) *BoltDB {
db, err := bolt.Open(filename+"/demo.db", 0600, nil)
if err != nil {
log.Fatal(err)
}
return &BoltDB{db}
}
type BoltDB struct {
db *bolt.DB
}
func (b *BoltDB) Path() string {
return b.db.Path()
}
func (b *BoltDB) Close() {
b.db.Close()
}
func (b *BoltDB) GetValue() int64 {
var retVal int64
err := b.db.View(func(tx *bolt.Tx) error {
b := tx.Bucket(demoBucket)
if b == nil {
retVal = -1
return nil
}
v := b.Get(demoKey)
if v == nil {
retVal = 0
} else {
i, err := binary.ReadVarint(bytes.NewBuffer(v))
if err != nil {
return err
}
retVal = i
}
return nil
})
if err != nil {
log.Fatal(err)
}
return retVal
}
func (b *BoltDB) Increment() int64 {
buf := make([]byte, 8)
var retVal int64
err := b.db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucketIfNotExists(demoBucket)
if err != nil {
log.Fatal(err)
}
v := b.Get(demoKey)
if v == nil {
binary.PutVarint(buf, 0)
retVal = 0
} else {
i, err := binary.ReadVarint(bytes.NewBuffer(v))
if err != nil {
log.Fatal(err)
}
i++
retVal = i
binary.PutVarint(buf, i)
}
err = b.Put(demoKey, buf)
return err
})
if err != nil {
log.Fatal(err)
}
return retVal
}