gorush/vendor/github.com/asdine/storm/metadata.go

70 lines
1.1 KiB
Go

package storm
import (
"reflect"
"github.com/boltdb/bolt"
)
const (
metaCodec = "codec"
)
func newMeta(b *bolt.Bucket, n Node) (*meta, error) {
m := b.Bucket([]byte(metadataBucket))
if m != nil {
name := m.Get([]byte(metaCodec))
if string(name) != n.Codec().Name() {
return nil, ErrDifferentCodec
}
return &meta{
node: n,
bucket: m,
}, nil
}
m, err := b.CreateBucket([]byte(metadataBucket))
if err != nil {
return nil, err
}
m.Put([]byte(metaCodec), []byte(n.Codec().Name()))
return &meta{
node: n,
bucket: m,
}, nil
}
type meta struct {
node Node
bucket *bolt.Bucket
}
func (m *meta) increment(field *fieldConfig) error {
var err error
counter := field.IncrementStart
raw := m.bucket.Get([]byte(field.Name + "counter"))
if raw != nil {
counter, err = numberfromb(raw)
if err != nil {
return err
}
counter++
}
raw, err = numbertob(counter)
if err != nil {
return err
}
err = m.bucket.Put([]byte(field.Name+"counter"), raw)
if err != nil {
return err
}
field.Value.Set(reflect.ValueOf(counter).Convert(field.Value.Type()))
field.IsZero = false
return nil
}