package filer import ( "bytes" "fmt" "golang.org/x/exp/slices" "io" "math" "sort" "strings" "sync" "time" "github.com/seaweedfs/seaweedfs/weed/glog" "github.com/seaweedfs/seaweedfs/weed/pb/filer_pb" "github.com/seaweedfs/seaweedfs/weed/stats" "github.com/seaweedfs/seaweedfs/weed/util" "github.com/seaweedfs/seaweedfs/weed/wdclient" ) var getLookupFileIdBackoffSchedule = []time.Duration{ 150 * time.Millisecond, 600 * time.Millisecond, 1800 * time.Millisecond, } func HasData(entry *filer_pb.Entry) bool { if len(entry.Content) > 0 { return true } return len(entry.Chunks) > 0 } func IsSameData(a, b *filer_pb.Entry) bool { if len(a.Content) > 0 || len(b.Content) > 0 { return bytes.Equal(a.Content, b.Content) } return isSameChunks(a.Chunks, b.Chunks) } func isSameChunks(a, b []*filer_pb.FileChunk) bool { if len(a) != len(b) { return false } slices.SortFunc(a, func(i, j *filer_pb.FileChunk) bool { return strings.Compare(i.ETag, j.ETag) < 0 }) slices.SortFunc(b, func(i, j *filer_pb.FileChunk) bool { return strings.Compare(i.ETag, j.ETag) < 0 }) for i := 0; i < len(a); i++ { if a[i].ETag != b[i].ETag { return false } } return true } func NewFileReader(filerClient filer_pb.FilerClient, entry *filer_pb.Entry) io.Reader { if len(entry.Content) > 0 { return bytes.NewReader(entry.Content) } return NewChunkStreamReader(filerClient, entry.Chunks) } func StreamContent(masterClient wdclient.HasLookupFileIdFunction, writer io.Writer, chunks []*filer_pb.FileChunk, offset int64, size int64) error { return StreamContentWithThrottler(masterClient, writer, chunks, offset, size, 0) } func StreamContentWithThrottler(masterClient wdclient.HasLookupFileIdFunction, writer io.Writer, chunks []*filer_pb.FileChunk, offset int64, size int64, downloadMaxBytesPs int64) error { glog.V(4).Infof("start to stream content for chunks: %d", len(chunks)) chunkViews := ViewFromChunks(masterClient.GetLookupFileIdFunction(), chunks, offset, size) fileId2Url := make(map[string][]string) for _, chunkView := range chunkViews { var urlStrings []string var err error for _, backoff := range getLookupFileIdBackoffSchedule { urlStrings, err = masterClient.GetLookupFileIdFunction()(chunkView.FileId) if err == nil && len(urlStrings) > 0 { break } glog.V(4).Infof("waiting for chunk: %s", chunkView.FileId) time.Sleep(backoff) } if err != nil { glog.V(1).Infof("operation LookupFileId %s failed, err: %v", chunkView.FileId, err) return err } else if len(urlStrings) == 0 { errUrlNotFound := fmt.Errorf("operation LookupFileId %s failed, err: urls not found", chunkView.FileId) glog.Error(errUrlNotFound) return errUrlNotFound } fileId2Url[chunkView.FileId] = urlStrings } downloadThrottler := util.NewWriteThrottler(downloadMaxBytesPs) remaining := size for _, chunkView := range chunkViews { if offset < chunkView.LogicOffset { gap := chunkView.LogicOffset - offset remaining -= gap glog.V(4).Infof("zero [%d,%d)", offset, chunkView.LogicOffset) err := writeZero(writer, gap) if err != nil { return fmt.Errorf("write zero [%d,%d)", offset, chunkView.LogicOffset) } offset = chunkView.LogicOffset } urlStrings := fileId2Url[chunkView.FileId] start := time.Now() err := retriedStreamFetchChunkData(writer, urlStrings, chunkView.CipherKey, chunkView.IsGzipped, chunkView.IsFullChunk(), chunkView.Offset, int(chunkView.Size)) offset += int64(chunkView.Size) remaining -= int64(chunkView.Size) stats.FilerRequestHistogram.WithLabelValues("chunkDownload").Observe(time.Since(start).Seconds()) if err != nil { stats.FilerRequestCounter.WithLabelValues("chunkDownloadError").Inc() return fmt.Errorf("read chunk: %v", err) } stats.FilerRequestCounter.WithLabelValues("chunkDownload").Inc() downloadThrottler.MaybeSlowdown(int64(chunkView.Size)) } if remaining > 0 { glog.V(4).Infof("zero [%d,%d)", offset, offset+remaining) err := writeZero(writer, remaining) if err != nil { return fmt.Errorf("write zero [%d,%d)", offset, offset+remaining) } } return nil } // ---------------- ReadAllReader ---------------------------------- func writeZero(w io.Writer, size int64) (err error) { zeroPadding := make([]byte, 1024) var written int for size > 0 { if size > 1024 { written, err = w.Write(zeroPadding) } else { written, err = w.Write(zeroPadding[:size]) } size -= int64(written) if err != nil { return } } return } func ReadAll(buffer []byte, masterClient *wdclient.MasterClient, chunks []*filer_pb.FileChunk) error { lookupFileIdFn := func(fileId string) (targetUrls []string, err error) { return masterClient.LookupFileId(fileId) } chunkViews := ViewFromChunks(lookupFileIdFn, chunks, 0, int64(len(buffer))) idx := 0 for _, chunkView := range chunkViews { urlStrings, err := lookupFileIdFn(chunkView.FileId) if err != nil { glog.V(1).Infof("operation LookupFileId %s failed, err: %v", chunkView.FileId, err) return err } n, err := retriedFetchChunkData(buffer[idx:idx+int(chunkView.Size)], urlStrings, chunkView.CipherKey, chunkView.IsGzipped, chunkView.IsFullChunk(), chunkView.Offset) if err != nil { return err } idx += n } return nil } // ---------------- ChunkStreamReader ---------------------------------- type ChunkStreamReader struct { chunkViews []*ChunkView totalSize int64 logicOffset int64 buffer []byte bufferOffset int64 bufferLock sync.Mutex chunk string lookupFileId wdclient.LookupFileIdFunctionType } var _ = io.ReadSeeker(&ChunkStreamReader{}) var _ = io.ReaderAt(&ChunkStreamReader{}) func doNewChunkStreamReader(lookupFileIdFn wdclient.LookupFileIdFunctionType, chunks []*filer_pb.FileChunk) *ChunkStreamReader { chunkViews := ViewFromChunks(lookupFileIdFn, chunks, 0, math.MaxInt64) slices.SortFunc(chunkViews, func(a, b *ChunkView) bool { return a.LogicOffset < b.LogicOffset }) var totalSize int64 for _, chunk := range chunkViews { totalSize += int64(chunk.Size) } return &ChunkStreamReader{ chunkViews: chunkViews, lookupFileId: lookupFileIdFn, totalSize: totalSize, } } func NewChunkStreamReaderFromFiler(masterClient *wdclient.MasterClient, chunks []*filer_pb.FileChunk) *ChunkStreamReader { lookupFileIdFn := func(fileId string) (targetUrl []string, err error) { return masterClient.LookupFileId(fileId) } return doNewChunkStreamReader(lookupFileIdFn, chunks) } func NewChunkStreamReader(filerClient filer_pb.FilerClient, chunks []*filer_pb.FileChunk) *ChunkStreamReader { lookupFileIdFn := LookupFn(filerClient) return doNewChunkStreamReader(lookupFileIdFn, chunks) } func (c *ChunkStreamReader) ReadAt(p []byte, off int64) (n int, err error) { c.bufferLock.Lock() defer c.bufferLock.Unlock() if err = c.prepareBufferFor(off); err != nil { return } c.logicOffset = off return c.doRead(p) } func (c *ChunkStreamReader) Read(p []byte) (n int, err error) { c.bufferLock.Lock() defer c.bufferLock.Unlock() return c.doRead(p) } func (c *ChunkStreamReader) doRead(p []byte) (n int, err error) { // fmt.Printf("do read [%d,%d) at %s[%d,%d)\n", c.logicOffset, c.logicOffset+int64(len(p)), c.chunk, c.bufferOffset, c.bufferOffset+int64(len(c.buffer))) for n < len(p) { // println("read", c.logicOffset) if err = c.prepareBufferFor(c.logicOffset); err != nil { return } t := copy(p[n:], c.buffer[c.logicOffset-c.bufferOffset:]) n += t c.logicOffset += int64(t) } return } func (c *ChunkStreamReader) isBufferEmpty() bool { return len(c.buffer) <= int(c.logicOffset-c.bufferOffset) } func (c *ChunkStreamReader) Seek(offset int64, whence int) (int64, error) { c.bufferLock.Lock() defer c.bufferLock.Unlock() var err error switch whence { case io.SeekStart: case io.SeekCurrent: offset += c.logicOffset case io.SeekEnd: offset = c.totalSize + offset } if offset > c.totalSize { err = io.ErrUnexpectedEOF } else { c.logicOffset = offset } return offset, err } func insideChunk(offset int64, chunk *ChunkView) bool { return chunk.LogicOffset <= offset && offset < chunk.LogicOffset+int64(chunk.Size) } func (c *ChunkStreamReader) prepareBufferFor(offset int64) (err error) { // stay in the same chunk if c.bufferOffset <= offset && offset < c.bufferOffset+int64(len(c.buffer)) { return nil } // fmt.Printf("fetch for offset %d\n", offset) // need to seek to a different chunk currentChunkIndex := sort.Search(len(c.chunkViews), func(i int) bool { return offset < c.chunkViews[i].LogicOffset }) if currentChunkIndex == len(c.chunkViews) { // not found if insideChunk(offset, c.chunkViews[0]) { // fmt.Printf("select0 chunk %d %s\n", currentChunkIndex, c.chunkViews[currentChunkIndex].FileId) currentChunkIndex = 0 } else if insideChunk(offset, c.chunkViews[len(c.chunkViews)-1]) { currentChunkIndex = len(c.chunkViews) - 1 // fmt.Printf("select last chunk %d %s\n", currentChunkIndex, c.chunkViews[currentChunkIndex].FileId) } else { return io.EOF } } else if currentChunkIndex > 0 { if insideChunk(offset, c.chunkViews[currentChunkIndex]) { // good hit } else if insideChunk(offset, c.chunkViews[currentChunkIndex-1]) { currentChunkIndex -= 1 // fmt.Printf("select -1 chunk %d %s\n", currentChunkIndex, c.chunkViews[currentChunkIndex].FileId) } else { // glog.Fatalf("unexpected1 offset %d", offset) return fmt.Errorf("unexpected1 offset %d", offset) } } else { // glog.Fatalf("unexpected2 offset %d", offset) return fmt.Errorf("unexpected2 offset %d", offset) } // positioning within the new chunk chunk := c.chunkViews[currentChunkIndex] if insideChunk(offset, chunk) { if c.isBufferEmpty() || c.bufferOffset != chunk.LogicOffset { if err = c.fetchChunkToBuffer(chunk); err != nil { return } } } else { // glog.Fatalf("unexpected3 offset %d in %s [%d,%d)", offset, chunk.FileId, chunk.LogicOffset, chunk.LogicOffset+int64(chunk.Size)) return fmt.Errorf("unexpected3 offset %d in %s [%d,%d)", offset, chunk.FileId, chunk.LogicOffset, chunk.LogicOffset+int64(chunk.Size)) } return } func (c *ChunkStreamReader) fetchChunkToBuffer(chunkView *ChunkView) error { urlStrings, err := c.lookupFileId(chunkView.FileId) if err != nil { glog.V(1).Infof("operation LookupFileId %s failed, err: %v", chunkView.FileId, err) return err } var buffer bytes.Buffer var shouldRetry bool for _, urlString := range urlStrings { shouldRetry, err = util.ReadUrlAsStream(urlString+"?readDeleted=true", chunkView.CipherKey, chunkView.IsGzipped, chunkView.IsFullChunk(), chunkView.Offset, int(chunkView.Size), func(data []byte) { buffer.Write(data) }) if !shouldRetry { break } if err != nil { glog.V(1).Infof("read %s failed, err: %v", chunkView.FileId, err) buffer.Reset() } else { break } } if err != nil { return err } c.buffer = buffer.Bytes() c.bufferOffset = chunkView.LogicOffset c.chunk = chunkView.FileId // glog.V(0).Infof("fetched %s [%d,%d)", chunkView.FileId, chunkView.LogicOffset, chunkView.LogicOffset+int64(chunkView.Size)) return nil } func (c *ChunkStreamReader) Close() { // TODO try to release and reuse buffer } func VolumeId(fileId string) string { lastCommaIndex := strings.LastIndex(fileId, ",") if lastCommaIndex > 0 { return fileId[:lastCommaIndex] } return fileId }