frostfs-node/pkg/local_object_storage/writecache/iterate.go
Leonard Lyubich ca4c9d4673 [] writecache: Implement iterator over small objects
There is a need to list addresses of the small objects stored in WriteCache
database.

Implement `IterateDB` function which accepts BoltDB instance and iterate
over all saved objects and passes their addresses to the hander.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2021-10-05 10:51:10 +03:00

42 lines
1 KiB
Go

package writecache
import (
"errors"
"fmt"
"github.com/nspcc-dev/neofs-api-go/pkg/object"
"go.etcd.io/bbolt"
)
// ErrNoDefaultBucket is returned by IterateDB when default bucket for objects is missing.
var ErrNoDefaultBucket = errors.New("no default bucket")
// IterateDB iterates over all objects stored in bbolt.DB instance and passes them to f until error return.
// It is assumed that db is an underlying database of some WriteCache instance.
//
// Returns ErrNoDefaultBucket if there is no default bucket in db.
//
// DB must not be nil and should be opened.
func IterateDB(db *bbolt.DB, f func(*object.Address) error) error {
return db.View(func(tx *bbolt.Tx) error {
b := tx.Bucket(defaultBucket)
if b == nil {
return ErrNoDefaultBucket
}
var addr *object.Address
return b.ForEach(func(k, v []byte) error {
if addr == nil {
addr = object.NewAddress()
}
err := addr.Parse(string(k))
if err != nil {
return fmt.Errorf("could not parse object address: %w", err)
}
return f(addr)
})
})
}