// RawDelete is a low-level function. It deletes a key-value pair using full keys
// without any context. This can be used in conjunction with RawRangeQuery.
func (db *BigTable) RawDelete(fullKey storage.Key) error {
if db == nil {
return fmt.Errorf("Can't call RawDelete() on nil BigTable")
}
unvKey, verKey, err := storage.SplitKey(fullKey)
if err != nil {
return fmt.Errorf("Error in RawDelete(): %v\n", err)
}
r, err := tbl.ReadRow(db.ctx, encodeKey(unvKey), api.RowFilter(api.StripValueFilter()))
//A missing row will return a zero-length map and a nil error
if len(r) == 0 {
return fmt.Errorf("Error in RawDelete(): This unvKey doesn't exists")
}
if err != nil {
return err
}
if len(r[familyName]) == 0 {
return fmt.Errorf("Error in Delete(): This row is empty")
}
_, err = getValue(r, verKey)
if err != nil {
return fmt.Errorf("Error in Delete(): The version to be deleted doesn't exist")
}
mut := api.NewMutation()
//There is only one version left, and is the one we are trying to delete\
//remove the whole row
if len(r[familyName]) == 1 {
mut.DeleteRow()
} else {
mut.DeleteCellsInColumn(familyName, encodeKey(verKey))
}
err = tbl.Apply(db.ctx, encodeKey(unvKey), mut)
if err != nil {
return fmt.Errorf("Error in Delete(): %v\n", err)
}
return err
}
// RawPut is a low-level function that puts a key-value pair using full keys.
// This can be used in conjunction with RawRangeQuery.
func (db *BigTable) RawPut(fullKey storage.Key, value []byte) error {
if db == nil {
return fmt.Errorf("Can't call RawPut() on nil BigTable")
}
unvKey, verKey, err := storage.SplitKey(fullKey)
if err != nil {
return fmt.Errorf("Error in RawPut(): %v\n", err)
}
mut := api.NewMutation()
mut.Set(familyName, encodeKey(verKey), 0, value)
err = tbl.Apply(db.ctx, encodeKey(unvKey), mut)
if err != nil {
return fmt.Errorf("Error in RawPut(): %v\n", err)
}
return err
}
// RawRangeQuery sends a range of full keys. This is to be used for low-level data
// retrieval like DVID-to-DVID communication and should not be used by data type
// implementations if possible because each version's key-value pairs are sent
// without filtering by the current version and its ancestor graph. A nil is sent
// down the channel when the range is complete.
func (db *BigTable) RawRangeQuery(kStart, kEnd storage.Key, keysOnly bool, out chan *storage.KeyValue, cancel <-chan struct{}) error {
if db == nil {
return fmt.Errorf("Can't call RawRangeQuery() on nil BigTable")
}
unvKeyBeg, verKeyBeg, err := storage.SplitKey(kStart)
if err != nil {
dvid.Errorf("Error in RawRangeQuery(): %v\n", err)
return err
}
unvKeyEnd, verKeyEnd, err := storage.SplitKey(kEnd)
if err != nil {
dvid.Errorf("Error in RawRangeQuery(): %v\n", err)
return err
}
rr := api.NewRange(encodeKey(unvKeyBeg), encodeKey(unvKeyEnd))
err = tbl.ReadRows(db.ctx, rr, func(r api.Row) bool {
if cancel != nil {
select {
case <-cancel:
out <- nil
return nil
default:
}
}
unvKeyRow, err := decodeKey(r.Key())
if err != nil {
dvid.Errorf("Error in RawRangeQuery(): %v\n", err)
return false
}
//I need the versioned key to merged it with the unversioned
// and send it throu the channel
for _, readItem := range r[familyName] {
verKey, err := decodeKey(readItem.Column)
if err != nil {
dvid.Errorf("Error in RawRangeQuery(): %v\n", err)
return false
}
lowerLimit := bytes.Equal(unvKeyBeg, unvKeyRow) && bytes.Compare(verKey, verKeyBeg) == -1
upperLimit := bytes.Equal(unvKeyEnd, unvKeyRow) && bytes.Compare(verKey, verKeyEnd) >= 0
if lowerLimit || upperLimit {
continue
}
fullKey := storage.MergeKey(unvKeyRow, verKey)
kv := storage.KeyValue{fullKey, readItem.Value}
out <- &kv
}
return true // keep going
})
return nil
}
