/*
Read a particular segmentFileName. Note that this may return IO error
if a commit is in process.
*/
func (sis *SegmentInfos) Read(directory store.Directory, segmentFileName string) (err error) {
// fmt.Printf("Reading segment info from %v...\n", segmentFileName)
// Clear any previous segments:
sis.Clear()
sis.generation = GenerationFromSegmentsFileName(segmentFileName)
sis.lastGeneration = sis.generation
var input store.ChecksumIndexInput
if input, err = directory.OpenChecksumInput(segmentFileName, store.IO_CONTEXT_READ); err != nil {
return
}
var success = false
defer func() {
if !success {
// Clear any segment infos we had loaded so we
// have a clean slate on retry:
sis.Clear()
util.CloseWhileSuppressingError(input)
} else {
err = input.Close()
}
}()
var format int
if format, err = asInt(input.ReadInt()); err != nil {
return
}
var actualFormat int
if format == codec.CODEC_MAGIC {
// 4.0+
if actualFormat, err = asInt(codec.CheckHeaderNoMagic(input, "segments", VERSION_40, VERSION_49)); err != nil {
return
}
if sis.version, err = input.ReadLong(); err != nil {
return
}
if sis.counter, err = asInt(input.ReadInt()); err != nil {
return
}
var numSegments int
if numSegments, err = asInt(input.ReadInt()); err != nil {
return
} else if numSegments < 0 {
return errors.New(fmt.Sprintf("invalid segment count: %v (resource: %v)", numSegments, input))
}
var segName, codecName string
var fCodec Codec
var delGen, fieldInfosGen, dvGen int64
var delCount int
for seg := 0; seg < numSegments; seg++ {
if segName, err = input.ReadString(); err != nil {
return
}
if codecName, err = input.ReadString(); err != nil {
return
}
fCodec = LoadCodec(codecName)
assert2(fCodec != nil, "Invalid codec name: %v", codecName)
// fmt.Printf("SIS.read seg=%v codec=%v\n", seg, fCodec)
var info *SegmentInfo
if info, err = fCodec.SegmentInfoFormat().SegmentInfoReader().Read(directory, segName, store.IO_CONTEXT_READ); err != nil {
return
}
info.SetCodec(fCodec)
if delGen, err = input.ReadLong(); err != nil {
return
}
if delCount, err = asInt(input.ReadInt()); err != nil {
return
} else if delCount < 0 || delCount > info.DocCount() {
return errors.New(fmt.Sprintf(
"invalid deletion count: %v vs docCount=%v (resource: %v)",
delCount, info.DocCount(), input))
}
fieldInfosGen = -1
if actualFormat >= VERSION_46 {
if fieldInfosGen, err = input.ReadLong(); err != nil {
return
}
}
dvGen = -1
if actualFormat >= VERSION_49 {
if dvGen, err = input.ReadLong(); err != nil {
return
}
} else {
dvGen = fieldInfosGen
}
siPerCommit := NewSegmentCommitInfo(info, delCount, delGen, fieldInfosGen, dvGen)
if actualFormat >= VERSION_46 {
if actualFormat < VERSION_49 {
panic("not implemented yet")
} else {
var ss map[string]bool
if ss, err = input.ReadStringSet(); err != nil {
return err
}
siPerCommit.SetFieldInfosFiles(ss)
var dvUpdatesFiles map[int]map[string]bool
var numDVFields int
if numDVFields, err = asInt(input.ReadInt()); err != nil {
return err
}
if numDVFields == 0 {
dvUpdatesFiles = make(map[int]map[string]bool)
} else {
panic("not implemented yet")
}
siPerCommit.SetDocValuesUpdatesFiles(dvUpdatesFiles)
}
}
sis.Segments = append(sis.Segments, siPerCommit)
}
if sis.userData, err = input.ReadStringStringMap(); err != nil {
return err
}
} else {
// TODO support <4.0 index
panic("Index format pre-4.0 not supported yet")
}
if actualFormat >= VERSION_48 {
if _, err = codec.CheckFooter(input); err != nil {
return
}
} else {
var checksumNow = int64(input.Checksum())
var checksumThen int64
if checksumThen, err = input.ReadLong(); err != nil {
return
}
if checksumNow != checksumThen {
return errors.New(fmt.Sprintf(
"checksum mismatch in segments file: %v vs %v (resource: %v)",
checksumNow, checksumThen, input))
}
if err = codec.CheckEOF(input); err != nil {
return
}
}
success = true
return nil
}
// TODO support IndexCommit
func (fsf *FindSegmentsFile) run(commit IndexCommit) (interface{}, error) {
// fmt.Println("Finding segments file...")
if commit != nil {
if fsf.directory != commit.Directory() {
return nil, errors.New("the specified commit does not match the specified Directory")
}
return fsf.doBody(commit.SegmentsFileName())
}
lastGen := int64(-1)
gen := int64(0)
genLookaheadCount := 0
var exc error
retryCount := 0
useFirstMethod := true
// Loop until we succeed in calling doBody() without
// hitting an IOException. An IOException most likely
// means a commit was in process and has finished, in
// the time it took us to load the now-old infos files
// (and segments files). It's also possible it's a
// true error (corrupt index). To distinguish these,
// on each retry we must see "forward progress" on
// which generation we are trying to load. If we
// don't, then the original error is real and we throw
// it.
// We have three methods for determining the current
// generation. We try the first two in parallel (when
// useFirstMethod is true), and fall back to the third
// when necessary.
for {
// fmt.Println("Trying...")
if useFirstMethod {
// fmt.Println("Trying first method...")
// List the directory and use the highest
// segments_N file. This method works well as long
// as there is no stale caching on the directory
// contents (NOTE: NFS clients often have such stale
// caching):
genA := int64(-1)
files, err := fsf.directory.ListAll()
if err != nil {
return nil, err
}
if files != nil {
genA = LastCommitGeneration(files)
}
// message("directory listing genA=%v", genA)
// Also open segments.gen and read its
// contents. Then we take the larger of the two
// gens. This way, if either approach is hitting
// a stale cache (NFS) we have a better chance of
// getting the right generation.
genB := int64(-1)
genInput, err := fsf.directory.OpenChecksumInput(INDEX_FILENAME_SEGMENTS_GEN, store.IO_CONTEXT_READ)
if err != nil {
message("segments.gen open: %v", err)
} else {
defer genInput.Close()
// fmt.Println("Reading segments info...")
var version int32
if version, err = genInput.ReadInt(); err != nil {
return nil, err
}
// fmt.Printf("Version: %v\n", version)
if version == FORMAT_SEGMENTS_GEN_47 || version == FORMAT_SEGMENTS_GEN_CURRENT {
// fmt.Println("Version is current.")
var gen0, gen1 int64
if gen0, err = genInput.ReadLong(); err != nil {
return nil, err
}
if gen1, err = genInput.ReadLong(); err != nil {
return nil, err
}
message("fallback check: %v; %v", gen0, gen1)
if version == FORMAT_SEGMENTS_GEN_CHECKSUM {
if _, err = codec.CheckFooter(genInput); err != nil {
return nil, err
}
} else {
if err = codec.CheckEOF(genInput); err != nil {
return nil, err
}
}
if gen0 == gen1 {
// The file is consistent.
genB = gen0
}
} else {
return nil, codec.NewIndexFormatTooNewError(genInput, version,
FORMAT_SEGMENTS_GEN_CURRENT, FORMAT_SEGMENTS_GEN_CURRENT)
}
}
message("%v check: genB=%v", INDEX_FILENAME_SEGMENTS_GEN, genB)
// Pick the larger of the two gen's:
gen = genA
if genB > gen {
gen = genB
}
if gen == -1 {
// Neither approach found a generation
return nil, errors.New(fmt.Sprintf("no segments* file found in %v: files: %#v", fsf.directory, files))
}
}
if useFirstMethod && lastGen == gen && retryCount >= 2 {
// Give up on first method -- this is 3rd cycle on
// listing directory and checking gen file to
// attempt to locate the segments file.
useFirstMethod = false
}
// Second method: since both directory cache and
// file contents cache seem to be stale, just
// advance the generation.
if !useFirstMethod {
if genLookaheadCount < fsf.defaultGenLookaheadCount {
gen++
genLookaheadCount++
message("look ahead increment gen to %v", gen)
} else {
// All attempts have failed -- throw first exc:
return nil, exc
}
} else if lastGen == gen {
// This means we're about to try the same
// segments_N last tried.
retryCount++
} else {
// Segment file has advanced since our last loop
// (we made "progress"), so reset retryCount:
retryCount = 0
}
lastGen = gen
segmentFileName := util.FileNameFromGeneration(INDEX_FILENAME_SEGMENTS, "", gen)
// fmt.Printf("SegmentFileName: %v\n", segmentFileName)
var v interface{}
var err error
if v, err = fsf.doBody(segmentFileName); err == nil {
message("success on %v", segmentFileName)
return v, nil
}
// Save the original root cause:
if exc == nil {
exc = err
}
message("primary Exception on '%v': %v; will retry: retryCount = %v; gen = %v",
segmentFileName, err, retryCount, gen)
if gen > 1 && useFirstMethod && retryCount == 1 {
// This is our second time trying this same segments
// file (because retryCount is 1), and, there is
// possibly a segments_(N-1) (because gen > 1).
// So, check if the segments_(N-1) exists and
// try it if so:
prevSegmentFileName := util.FileNameFromGeneration(INDEX_FILENAME_SEGMENTS, "", gen-1)
if prevExists := fsf.directory.FileExists(prevSegmentFileName); prevExists {
message("fallback to prior segment file '%v'", prevSegmentFileName)
if v, err = fsf.doBody(prevSegmentFileName); err != nil {
message("secondary Exception on '%v': %v; will retry", prevSegmentFileName, err)
} else {
message("success on fallback %v", prevSegmentFileName)
return v, nil
}
}
}
}
}
// Sole constructor
func newCompressingStoredFieldsReader(d store.Directory,
si *model.SegmentInfo, segmentSuffix string,
fn model.FieldInfos, ctx store.IOContext, formatName string,
compressionMode CompressionMode) (r *CompressingStoredFieldsReader, err error) {
r = &CompressingStoredFieldsReader{}
r.compressionMode = compressionMode
segment := si.Name
r.fieldInfos = fn
r.numDocs = si.DocCount()
var indexStream store.ChecksumIndexInput
success := false
defer func() {
if !success {
util.CloseWhileSuppressingError(r, indexStream)
}
}()
indexStreamFN := util.SegmentFileName(segment, segmentSuffix, lucene40.FIELDS_INDEX_EXTENSION)
fieldsStreamFN := util.SegmentFileName(segment, segmentSuffix, lucene40.FIELDS_EXTENSION)
// Load the index into memory
if indexStream, err = d.OpenChecksumInput(indexStreamFN, ctx); err != nil {
return nil, err
}
codecNameIdx := formatName + CODEC_SFX_IDX
if r.version, err = int32AsInt(codec.CheckHeader(indexStream, codecNameIdx,
VERSION_START, VERSION_CURRENT)); err != nil {
return nil, err
}
assert(int64(codec.HeaderLength(codecNameIdx)) == indexStream.FilePointer())
if r.indexReader, err = newCompressingStoredFieldsIndexReader(indexStream, si); err != nil {
return nil, err
}
var maxPointer int64 = -1
if r.version >= VERSION_CHECKSUM {
if maxPointer, err = indexStream.ReadVLong(); err != nil {
return nil, err
}
if _, err = codec.CheckFooter(indexStream); err != nil {
return nil, err
}
} else {
if err = codec.CheckEOF(indexStream); err != nil {
return nil, err
}
}
if err = indexStream.Close(); err != nil {
return nil, err
}
indexStream = nil
// Open the data file and read metadata
if r.fieldsStream, err = d.OpenInput(fieldsStreamFN, ctx); err != nil {
return nil, err
}
if r.version >= VERSION_CHECKSUM {
if maxPointer+codec.FOOTER_LENGTH != r.fieldsStream.Length() {
return nil, errors.New(fmt.Sprintf(
"Invalid fieldsStream maxPointer (file truncated?): maxPointer=%v, length=%v",
maxPointer, r.fieldsStream.Length()))
}
} else {
maxPointer = r.fieldsStream.Length()
}
r.maxPointer = maxPointer
codecNameDat := formatName + CODEC_SFX_DAT
var fieldsVersion int
if fieldsVersion, err = int32AsInt(codec.CheckHeader(r.fieldsStream,
codecNameDat, VERSION_START, VERSION_CURRENT)); err != nil {
return nil, err
}
assert2(r.version == fieldsVersion,
"Version mismatch between stored fields index and data: %v != %v",
r.version, fieldsVersion)
assert(int64(codec.HeaderLength(codecNameDat)) == r.fieldsStream.FilePointer())
r.chunkSize = -1
if r.version >= VERSION_BIG_CHUNKS {
if r.chunkSize, err = int32AsInt(r.fieldsStream.ReadVInt()); err != nil {
return nil, err
}
}
if r.packedIntsVersion, err = int32AsInt(r.fieldsStream.ReadVInt()); err != nil {
return nil, err
}
r.decompressor = compressionMode.NewDecompressor()
r.bytes = make([]byte, 0)
if r.version >= VERSION_CHECKSUM {
// NOTE: data file is too costly to verify checksum against all the
// bytes on open, but fo rnow we at least verify proper structure
// of the checksum footer: which looks for FOOTER_MATIC +
// algorithmID. This is cheap and can detect some forms of
// corruption such as file trucation.
if _, err = codec.RetrieveChecksum(r.fieldsStream); err != nil {
return nil, err
}
}
success = true
return r, nil
}
return
}
if attributes, err = input.ReadStringStringMap(); err != nil {
return
}
infos = append(infos, NewFieldInfo(name, isIndexed, fieldNumber,
storeTermVector, omitNorms, storePayloads, indexOptions,
docValuesType, normsType, dvGen, attributes))
}
if codecVersion >= FI_FORMAT_CHECKSUM {
if _, err = codec.CheckFooter(input); err != nil {
return
}
} else {
if err = codec.CheckEOF(input); err != nil {
return
}
}
fis = NewFieldInfos(infos)
success = true
return fis, nil
}
func getDocValuesType(input store.IndexInput, b byte) (t DocValuesType, err error) {
switch b {
case 0:
return DocValuesType(0), nil
case 1:
return DOC_VALUES_TYPE_NUMERIC, nil
case 2:
func (d *CompoundFileDirectory) readEntries(handle IndexInput, dir Directory, name string) (mapping map[string]FileSlice, err error) {
var stream IndexInput = nil
var entriesStream ChecksumIndexInput = nil
// read the first VInt. If it is negative, it's the version number
// otherwise it's the count (pre-3.1 indexes)
var success = false
defer func() {
if success {
err = util.Close(stream, entriesStream)
} else {
util.CloseWhileSuppressingError(stream, entriesStream)
}
}()
stream = handle.Clone()
// fmt.Printf("Reading from stream: %v\n", stream)
firstInt, err := stream.ReadVInt()
if err != nil {
return nil, err
}
// impossible for 3.0 to have 63 files in a .cfs, CFS writer was not visible
// and separate norms/etc are outside of cfs.
if firstInt == int32(CODEC_MAGIC_BYTE1) {
if secondByte, err := stream.ReadByte(); err == nil {
if thirdByte, err := stream.ReadByte(); err == nil {
if fourthByte, err := stream.ReadByte(); err == nil {
if secondByte != CODEC_MAGIC_BYTE2 ||
thirdByte != CODEC_MAGIC_BYTE3 ||
fourthByte != CODEC_MAGIC_BYTE4 {
return nil, errors.New(fmt.Sprintf(
"Illegal/impossible header for CFS file: %v,%v,%v",
secondByte, thirdByte, fourthByte))
}
}
}
}
if err != nil {
return nil, err
}
d.version, err = int32ToInt(codec.CheckHeaderNoMagic(stream, CFD_DATA_CODEC, CFD_VERSION_START, CFD_VERSION_CURRENT))
if err != nil {
return nil, err
}
entriesFileName := util.SegmentFileName(util.StripExtension(name), "", COMPOUND_FILE_ENTRIES_EXTENSION)
entriesStream, err = dir.OpenChecksumInput(entriesFileName, IO_CONTEXT_READONCE)
if err != nil {
return nil, err
}
_, err = codec.CheckHeader(entriesStream, CFD_ENTRY_CODEC, CFD_VERSION_START, CFD_VERSION_CURRENT)
if err != nil {
return nil, err
}
numEntries, err := entriesStream.ReadVInt()
if err != nil {
return nil, err
}
mapping = make(map[string]FileSlice)
// fmt.Printf("Entries number: %v\n", numEntries)
for i := int32(0); i < numEntries; i++ {
id, err := entriesStream.ReadString()
if err != nil {
return nil, err
}
if _, ok := mapping[id]; ok {
return nil, errors.New(fmt.Sprintf(
"Duplicate cfs entry id=%v in CFS: %v", id, entriesStream))
}
// log.Printf("Found entry: %v", id)
offset, err := entriesStream.ReadLong()
if err != nil {
return nil, err
}
length, err := entriesStream.ReadLong()
if err != nil {
return nil, err
}
mapping[id] = FileSlice{offset, length}
}
if d.version >= CFD_VERSION_CHECKSUM {
_, err = codec.CheckFooter(entriesStream)
} else {
err = codec.CheckEOF(entriesStream)
}
if err != nil {
return nil, err
}
} else {
// TODO remove once 3.x is not supported anymore
panic("not supported yet; will also be obsolete soon")
}
success = true
return mapping, nil
}
func (r *Lucene40SegmentInfoReader) Read(dir store.Directory,
segment string, context store.IOContext) (si *SegmentInfo, err error) {
si = new(SegmentInfo)
fileName := util.SegmentFileName(segment, "", LUCENE40_SI_EXTENSION)
input, err := dir.OpenInput(fileName, context)
if err != nil {
return nil, err
}
success := false
defer func() {
if !success {
util.CloseWhileSuppressingError(input)
} else {
input.Close()
}
}()
_, err = codec.CheckHeader(input, LUCENE40_CODEC_NAME, LUCENE40_VERSION_START, LUCENE40_VERSION_CURRENT)
if err != nil {
return nil, err
}
versionStr, err := input.ReadString()
if err != nil {
return nil, err
}
version, err := util.ParseVersion(versionStr)
if err != nil {
return nil, err
}
docCount, err := input.ReadInt()
if err != nil {
return nil, err
}
if docCount < 0 {
return nil, errors.New(fmt.Sprintf("invalid docCount: %v (resource=%v)", docCount, input))
}
sicf, err := input.ReadByte()
if err != nil {
return nil, err
}
isCompoundFile := (sicf == SEGMENT_INFO_YES)
diagnostics, err := input.ReadStringStringMap()
if err != nil {
return nil, err
}
_, err = input.ReadStringStringMap() // read deprecated attributes
if err != nil {
return nil, err
}
files, err := input.ReadStringSet()
if err != nil {
return nil, err
}
if err = codec.CheckEOF(input); err != nil {
return nil, err
}
si = NewSegmentInfo(dir, version, segment, int(docCount), isCompoundFile, nil, diagnostics)
si.SetFiles(files)
success = true
return si, nil
}
