func defragdb(odb, tmpdb *bolt.DB, limit int) error {
// open a tx on tmpdb for writes
tmptx, err := tmpdb.Begin(true)
if err != nil {
return err
}
// open a tx on old db for read
tx, err := odb.Begin(false)
if err != nil {
return err
}
defer tx.Rollback()
c := tx.Cursor()
count := 0
for next, _ := c.First(); next != nil; next, _ = c.Next() {
b := tx.Bucket(next)
if b == nil {
return fmt.Errorf("backend: cannot defrag bucket %s", string(next))
}
tmpb, berr := tmptx.CreateBucketIfNotExists(next)
if berr != nil {
return berr
}
b.ForEach(func(k, v []byte) error {
count++
if count > limit {
err = tmptx.Commit()
if err != nil {
return err
}
tmptx, err = tmpdb.Begin(true)
if err != nil {
return err
}
tmpb = tmptx.Bucket(next)
}
err = tmpb.Put(k, v)
if err != nil {
return err
}
return nil
})
}
return tmptx.Commit()
}
// Ensure that opening a transaction while the DB is closed returns an error.
func TestDB_BeginRW_Closed(t *testing.T) {
var db bolt.DB
tx, err := db.Begin(true)
equals(t, err, bolt.ErrDatabaseNotOpen)
assert(t, tx == nil, "")
}
// Ensure that a database cannot open a transaction when it's not open.
func TestDB_Begin_DatabaseNotOpen(t *testing.T) {
var db bolt.DB
tx, err := db.Begin(false)
assert(t, tx == nil, "")
equals(t, err, bolt.ErrDatabaseNotOpen)
}