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

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package storm
import (
"reflect"
"github.com/boltdb/bolt"
)
// KeyValueStore can store and fetch values by key
type KeyValueStore interface {
// Get a value from a bucket
Get(bucketName string, key interface{}, to interface{}) error
// Set a key/value pair into a bucket
Set(bucketName string, key interface{}, value interface{}) error
// Delete deletes a key from a bucket
Delete(bucketName string, key interface{}) error
// GetBytes gets a raw value from a bucket.
GetBytes(bucketName string, key interface{}) ([]byte, error)
// SetBytes sets a raw value into a bucket.
SetBytes(bucketName string, key interface{}, value []byte) error
}
// GetBytes gets a raw value from a bucket.
func (n *node) GetBytes(bucketName string, key interface{}) ([]byte, error) {
id, err := toBytes(key, n.s.codec)
if err != nil {
return nil, err
}
var val []byte
return val, n.readTx(func(tx *bolt.Tx) error {
raw, err := n.getBytes(tx, bucketName, id)
if err != nil {
return err
}
val = make([]byte, len(raw))
copy(val, raw)
return nil
})
}
// GetBytes gets a raw value from a bucket.
func (n *node) getBytes(tx *bolt.Tx, bucketName string, id []byte) ([]byte, error) {
bucket := n.GetBucket(tx, bucketName)
if bucket == nil {
return nil, ErrNotFound
}
raw := bucket.Get(id)
if raw == nil {
return nil, ErrNotFound
}
return raw, nil
}
// SetBytes sets a raw value into a bucket.
func (n *node) SetBytes(bucketName string, key interface{}, value []byte) error {
if key == nil {
return ErrNilParam
}
id, err := toBytes(key, n.s.codec)
if err != nil {
return err
}
return n.readWriteTx(func(tx *bolt.Tx) error {
return n.setBytes(tx, bucketName, id, value)
})
}
func (n *node) setBytes(tx *bolt.Tx, bucketName string, id, data []byte) error {
bucket, err := n.CreateBucketIfNotExists(tx, bucketName)
if err != nil {
return err
}
// save node configuration in the bucket
_, err = newMeta(bucket, n)
if err != nil {
return err
}
return bucket.Put(id, data)
}
// Get a value from a bucket
func (n *node) Get(bucketName string, key interface{}, to interface{}) error {
ref := reflect.ValueOf(to)
if !ref.IsValid() || ref.Kind() != reflect.Ptr {
return ErrPtrNeeded
}
id, err := toBytes(key, n.s.codec)
if err != nil {
return err
}
return n.readTx(func(tx *bolt.Tx) error {
raw, err := n.getBytes(tx, bucketName, id)
if err != nil {
return err
}
return n.s.codec.Unmarshal(raw, to)
})
}
// Set a key/value pair into a bucket
func (n *node) Set(bucketName string, key interface{}, value interface{}) error {
var data []byte
var err error
if value != nil {
data, err = n.s.codec.Marshal(value)
if err != nil {
return err
}
}
return n.SetBytes(bucketName, key, data)
}
// Delete deletes a key from a bucket
func (n *node) Delete(bucketName string, key interface{}) error {
id, err := toBytes(key, n.s.codec)
if err != nil {
return err
}
return n.readWriteTx(func(tx *bolt.Tx) error {
return n.delete(tx, bucketName, id)
})
}
func (n *node) delete(tx *bolt.Tx, bucketName string, id []byte) error {
bucket := n.GetBucket(tx, bucketName)
if bucket == nil {
return ErrNotFound
}
return bucket.Delete(id)
}