func (udc *UpsideDownCouch) backIndexRowForDoc(kvreader store.KVReader, docID string) (*BackIndexRow, error) {
// use a temporary row structure to build key
tempRow := &BackIndexRow{
doc: []byte(docID),
}
keyBuf := GetRowBuffer()
if tempRow.KeySize() > len(keyBuf) {
keyBuf = make([]byte, 2*tempRow.KeySize())
}
defer PutRowBuffer(keyBuf)
keySize, err := tempRow.KeyTo(keyBuf)
if err != nil {
return nil, err
}
value, err := kvreader.Get(keyBuf[:keySize])
if err != nil {
return nil, err
}
if value == nil {
return nil, nil
}
backIndexRow, err := NewBackIndexRowKV(keyBuf[:keySize], value)
if err != nil {
return nil, err
}
return backIndexRow, nil
}
func (f *Firestorm) checkVersion(reader store.KVReader) (newIndex bool, err error) {
value, err := reader.Get(VersionKey)
if err != nil {
return
}
if value == nil {
newIndex = true
return
}
var vr *VersionRow
vr, err = NewVersionRowV(value)
if err != nil {
return
}
// assert correct version
if vr.Version() != Version {
err = IncompatibleVersion
return
}
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
}
func (udc *UpsideDownCouch) Open() (err error) {
//acquire the write mutex for the duratin of Open()
udc.writeMutex.Lock()
defer udc.writeMutex.Unlock()
// open the kv store
storeConstructor := registry.KVStoreConstructorByName(udc.storeName)
if storeConstructor == nil {
err = index.ErrorUnknownStorageType
return
}
// now open the store
udc.store, err = storeConstructor(&mergeOperator, udc.storeConfig)
if err != nil {
return
}
// start a reader to look at the index
var kvreader store.KVReader
kvreader, err = udc.store.Reader()
if err != nil {
return
}
var value []byte
value, err = kvreader.Get(VersionKey)
if err != nil {
_ = kvreader.Close()
return
}
if value != nil {
err = udc.loadSchema(kvreader)
if err != nil {
_ = kvreader.Close()
return
}
// set doc count
udc.m.Lock()
udc.docCount, err = udc.countDocs(kvreader)
udc.m.Unlock()
err = kvreader.Close()
} else {
// new index, close the reader and open writer to init
err = kvreader.Close()
if err != nil {
return
}
var kvwriter store.KVWriter
kvwriter, err = udc.store.Writer()
if err != nil {
return
}
defer func() {
if cerr := kvwriter.Close(); err == nil && cerr != nil {
err = cerr
}
}()
// init the index
err = udc.init(kvwriter)
}
return
}