func (udc *UpsideDownCouch) dumpPrefix(kvreader store.KVReader, rv chan interface{}, prefix []byte) {
start := prefix
if start == nil {
start = []byte{0}
}
it := kvreader.PrefixIterator(start)
defer func() {
cerr := it.Close()
if cerr != nil {
rv <- cerr
}
}()
key, val, valid := it.Current()
for valid {
ck := make([]byte, len(key))
copy(ck, key)
cv := make([]byte, len(val))
copy(cv, val)
row, err := ParseFromKeyValue(ck, cv)
if err != nil {
rv <- err
return
}
rv <- row
it.Next()
key, val, valid = it.Current()
}
}
func visitPrefix(reader store.KVReader, prefix []byte, visitor KVVisitor) (err error) {
start := prefix
if start == nil {
start = []byte{0}
}
it := reader.PrefixIterator(prefix)
defer func() {
if cerr := it.Close(); err == nil && cerr != nil {
err = cerr
}
}()
k, v, valid := it.Current()
for valid {
var cont bool
cont, err = visitor(k, v)
if err != nil {
// visitor encountered an error, stop and return it
return
}
if !cont {
// vistor has requested we stop iteration, return nil
return
}
it.Next()
k, v, valid = it.Current()
}
return
}
func (udc *UpsideDownCouch) countDocs(kvreader store.KVReader) (count uint64, err error) {
it := kvreader.PrefixIterator([]byte{'b'})
defer func() {
if cerr := it.Close(); err == nil && cerr != nil {
err = cerr
}
}()
_, _, valid := it.Current()
for valid {
count++
it.Next()
_, _, valid = it.Current()
}
return
}
func (udc *UpsideDownCouch) loadSchema(kvreader store.KVReader) (err error) {
it := kvreader.PrefixIterator([]byte{'f'})
defer func() {
if cerr := it.Close(); err == nil && cerr != nil {
err = cerr
}
}()
key, val, valid := it.Current()
for valid {
var fieldRow *FieldRow
fieldRow, err = NewFieldRowKV(key, val)
if err != nil {
return
}
udc.fieldCache.AddExisting(fieldRow.name, fieldRow.index)
it.Next()
key, val, valid = it.Current()
}
val, err = kvreader.Get([]byte{'v'})
if err != nil {
return
}
var vr *VersionRow
vr, err = NewVersionRowKV([]byte{'v'}, val)
if err != nil {
return
}
if vr.version != Version {
err = IncompatibleVersion
return
}
return
}