1 files changed, 168 insertions, 0 deletions
diff --git a/weed/filer/filechunk_manifest.go b/weed/filer/filechunk_manifest.go
new file mode 100644
index 000000000..e84cf21e5
--- /dev/null
+++ b/weed/filer/filechunk_manifest.go
@@ -0,0 +1,168 @@
+package filer
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+
+	"github.com/golang/protobuf/proto"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/util"
+)
+
+const (
+	ManifestBatch = 1000
+)
+
+func HasChunkManifest(chunks []*filer_pb.FileChunk) bool {
+	for _, chunk := range chunks {
+		if chunk.IsChunkManifest {
+			return true
+		}
+	}
+	return false
+}
+
+func SeparateManifestChunks(chunks []*filer_pb.FileChunk) (manifestChunks, nonManifestChunks []*filer_pb.FileChunk) {
+	for _, c := range chunks {
+		if c.IsChunkManifest {
+			manifestChunks = append(manifestChunks, c)
+		} else {
+			nonManifestChunks = append(nonManifestChunks, c)
+		}
+	}
+	return
+}
+
+func ResolveChunkManifest(lookupFileIdFn LookupFileIdFunctionType, chunks []*filer_pb.FileChunk) (dataChunks, manifestChunks []*filer_pb.FileChunk, manifestResolveErr error) {
+	// TODO maybe parallel this
+	for _, chunk := range chunks {
+		if !chunk.IsChunkManifest {
+			dataChunks = append(dataChunks, chunk)
+			continue
+		}
+
+		resolvedChunks, err := ResolveOneChunkManifest(lookupFileIdFn, chunk)
+		if err != nil {
+			return chunks, nil, err
+		}
+
+		manifestChunks = append(manifestChunks, chunk)
+		// recursive
+		dchunks, mchunks, subErr := ResolveChunkManifest(lookupFileIdFn, resolvedChunks)
+		if subErr != nil {
+			return chunks, nil, subErr
+		}
+		dataChunks = append(dataChunks, dchunks...)
+		manifestChunks = append(manifestChunks, mchunks...)
+	}
+	return
+}
+
+func ResolveOneChunkManifest(lookupFileIdFn LookupFileIdFunctionType, chunk *filer_pb.FileChunk) (dataChunks []*filer_pb.FileChunk, manifestResolveErr error) {
+	if !chunk.IsChunkManifest {
+		return
+	}
+
+	// IsChunkManifest
+	data, err := fetchChunk(lookupFileIdFn, chunk.GetFileIdString(), chunk.CipherKey, chunk.IsCompressed)
+	if err != nil {
+		return nil, fmt.Errorf("fail to read manifest %s: %v", chunk.GetFileIdString(), err)
+	}
+	m := &filer_pb.FileChunkManifest{}
+	if err := proto.Unmarshal(data, m); err != nil {
+		return nil, fmt.Errorf("fail to unmarshal manifest %s: %v", chunk.GetFileIdString(), err)
+	}
+
+	// recursive
+	filer_pb.AfterEntryDeserialization(m.Chunks)
+	return m.Chunks, nil
+}
+
+// TODO fetch from cache for weed mount?
+func fetchChunk(lookupFileIdFn LookupFileIdFunctionType, fileId string, cipherKey []byte, isGzipped bool) ([]byte, error) {
+	urlString, err := lookupFileIdFn(fileId)
+	if err != nil {
+		glog.Errorf("operation LookupFileId %s failed, err: %v", fileId, err)
+		return nil, err
+	}
+	var buffer bytes.Buffer
+	err = util.ReadUrlAsStream(urlString+"?readDeleted=true", cipherKey, isGzipped, true, 0, 0, func(data []byte) {
+		buffer.Write(data)
+	})
+	if err != nil {
+		glog.V(0).Infof("read %s failed, err: %v", fileId, err)
+		return nil, err
+	}
+
+	return buffer.Bytes(), nil
+}
+
+func MaybeManifestize(saveFunc SaveDataAsChunkFunctionType, inputChunks []*filer_pb.FileChunk) (chunks []*filer_pb.FileChunk, err error) {
+	return doMaybeManifestize(saveFunc, inputChunks, ManifestBatch, mergeIntoManifest)
+}
+
+func doMaybeManifestize(saveFunc SaveDataAsChunkFunctionType, inputChunks []*filer_pb.FileChunk, mergeFactor int, mergefn func(saveFunc SaveDataAsChunkFunctionType, dataChunks []*filer_pb.FileChunk) (manifestChunk *filer_pb.FileChunk, err error)) (chunks []*filer_pb.FileChunk, err error) {
+
+	var dataChunks []*filer_pb.FileChunk
+	for _, chunk := range inputChunks {
+		if !chunk.IsChunkManifest {
+			dataChunks = append(dataChunks, chunk)
+		} else {
+			chunks = append(chunks, chunk)
+		}
+	}
+
+	remaining := len(dataChunks)
+	for i := 0; i+mergeFactor <= len(dataChunks); i += mergeFactor {
+		chunk, err := mergefn(saveFunc, dataChunks[i:i+mergeFactor])
+		if err != nil {
+			return dataChunks, err
+		}
+		chunks = append(chunks, chunk)
+		remaining -= mergeFactor
+	}
+	// remaining
+	for i := len(dataChunks) - remaining; i < len(dataChunks); i++ {
+		chunks = append(chunks, dataChunks[i])
+	}
+	return
+}
+
+func mergeIntoManifest(saveFunc SaveDataAsChunkFunctionType, dataChunks []*filer_pb.FileChunk) (manifestChunk *filer_pb.FileChunk, err error) {
+
+	filer_pb.BeforeEntrySerialization(dataChunks)
+
+	// create and serialize the manifest
+	data, serErr := proto.Marshal(&filer_pb.FileChunkManifest{
+		Chunks: dataChunks,
+	})
+	if serErr != nil {
+		return nil, fmt.Errorf("serializing manifest: %v", serErr)
+	}
+
+	minOffset, maxOffset := int64(math.MaxInt64), int64(math.MinInt64)
+	for _, chunk := range dataChunks {
+		if minOffset > int64(chunk.Offset) {
+			minOffset = chunk.Offset
+		}
+		if maxOffset < int64(chunk.Size)+chunk.Offset {
+			maxOffset = int64(chunk.Size) + chunk.Offset
+		}
+	}
+
+	manifestChunk, _, _, err = saveFunc(bytes.NewReader(data), "", 0)
+	if err != nil {
+		return nil, err
+	}
+	manifestChunk.IsChunkManifest = true
+	manifestChunk.Offset = minOffset
+	manifestChunk.Size = uint64(maxOffset - minOffset)
+
+	return
+}
+
+type SaveDataAsChunkFunctionType func(reader io.Reader, name string, offset int64) (chunk *filer_pb.FileChunk, collection, replication string, err error)