stream read large files

weed/server/volume_server_handlers_read.go

@@ -127,6 +127,7 @@ func (vs *VolumeServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request)
 
 	var count int
 	var needleSize types.Size
+	readOption.AttemptMetaOnly, readOption.MustMetaOnly = shouldAttemptStreamWrite(hasVolume, ext, r)
 	onReadSizeFn := func(size types.Size) {
 		needleSize = size
 		atomic.AddInt64(&vs.inFlightDownloadDataSize, int64(needleSize))
@@ -218,11 +219,31 @@ func (vs *VolumeServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request)
 		}
 	}
 
-	rs := conditionallyResizeImages(bytes.NewReader(n.Data), ext, r)
+	if !readOption.IsMetaOnly {
+		rs := conditionallyResizeImages(bytes.NewReader(n.Data), ext, r)
+		if e := writeResponseContent(filename, mtype, rs, w, r); e != nil {
+			glog.V(2).Infoln("response write error:", e)
+		}
+	} else {
+		vs.streamWriteResponseContent(filename, mtype, volumeId, n, w, r, readOption)
+	}
+}
 
-	if e := writeResponseContent(filename, mtype, rs, w, r); e != nil {
-		glog.V(2).Infoln("response write error:", e)
+func shouldAttemptStreamWrite(hasLocalVolume bool, ext string, r *http.Request) (shouldAttempt bool, mustMetaOnly bool) {
+	if !hasLocalVolume {
+		return false, false
+	}
+	if len(ext) > 0 {
+		ext = strings.ToLower(ext)
+	}
+	if r.Method == "HEAD" {
+		return true, true
+	}
+	_, _, _, shouldResize := shouldResizeImages(ext, r)
+	if shouldResize {
+		return false, false
 	}
+	return true, false
 }
 
 func (vs *VolumeServer) tryHandleChunkedFile(n *needle.Needle, fileName string, ext string, w http.ResponseWriter, r *http.Request) (processed bool) {
@@ -318,3 +339,27 @@ func writeResponseContent(filename, mimeType string, rs io.ReadSeeker, w http.Re
 	})
 	return nil
 }
+
+func (vs *VolumeServer) streamWriteResponseContent(filename string, mimeType string, volumeId needle.VolumeId, n *needle.Needle, w http.ResponseWriter, r *http.Request, readOption *storage.ReadOption) {
+	totalSize := int64(n.DataSize)
+	if mimeType == "" {
+		if ext := filepath.Ext(filename); ext != "" {
+			mimeType = mime.TypeByExtension(ext)
+		}
+	}
+	if mimeType != "" {
+		w.Header().Set("Content-Type", mimeType)
+	}
+	w.Header().Set("Accept-Ranges", "bytes")
+	adjustPassthroughHeaders(w, r, filename)
+
+	if r.Method == "HEAD" {
+		w.Header().Set("Content-Length", strconv.FormatInt(totalSize, 10))
+		return
+	}
+
+	processRangeRequest(r, w, totalSize, mimeType, func(writer io.Writer, offset int64, size int64) error {
+		return vs.store.ReadVolumeNeedleDataInto(volumeId, n, readOption, writer, offset, size)
+	})
+
+}

weed/storage/needle/needle_read_page.go

@@ -10,26 +10,28 @@ import (
 )
 
 // ReadNeedleDataInto uses a needle without n.Data to read the content into an io.Writer
-func (n *Needle) ReadNeedleDataInto(r backend.BackendStorageFile, offset int64, buf []byte, writer io.Writer, expectedChecksumValue uint32) (err error) {
+func (n *Needle) ReadNeedleDataInto(r backend.BackendStorageFile, volumeOffset int64, buf []byte, writer io.Writer, needleOffset int64, size int64, expectedChecksumValue uint32) (err error) {
 	crc := CRC(0)
-	for x := 0; ; x += len(buf) {
-		count, err := n.ReadNeedleData(r, offset, buf, int64(x))
+	for x := needleOffset; x < needleOffset+size; x += int64(len(buf)) {
+		count, err := n.ReadNeedleData(r, volumeOffset, buf, x)
+		if count > 0 {
+			crc = crc.Update(buf[0:count])
+			if _, err = writer.Write(buf[0:count]); err != nil {
+				return fmt.Errorf("ReadNeedleData write: %v", err)
+			}
+		}
 		if err != nil {
 			if err == io.EOF {
+				err = nil
 				break
 			}
 			return fmt.Errorf("ReadNeedleData: %v", err)
 		}
-		if count > 0 {
-			crc = crc.Update(buf[0:count])
-			if _, err = writer.Write(buf[0:count]); err != nil {
-				return fmt.Errorf("ReadNeedleData write: %v", err)
-			}
-		} else {
+		if count <= 0 {
 			break
 		}
 	}
-	if expectedChecksumValue != crc.Value() {
+	if needleOffset == 0 && size == int64(n.DataSize) && expectedChecksumValue != crc.Value() {
 		return fmt.Errorf("ReadNeedleData checksum %v expected %v", crc.Value(), expectedChecksumValue)
 	}
 	return nil
@@ -65,14 +67,18 @@ func (n *Needle) ReadNeedleMeta(r backend.BackendStorageFile, offset int64, size
 		return 0, err
 	}
 	n.ParseNeedleHeader(bytes)
+	if n.Size != size {
+		if OffsetSize == 4 && offset < int64(MaxPossibleVolumeSize) {
+			return 0, ErrorSizeMismatch
+		}
+	}
+
 	n.DataSize = util.BytesToUint32(bytes[NeedleHeaderSize : NeedleHeaderSize+DataSizeSize])
 
 	startOffset := offset + NeedleHeaderSize + DataSizeSize + int64(n.DataSize)
 	dataSize := GetActualSize(size, version)
 	stopOffset := offset + dataSize
 	metaSize := stopOffset - startOffset
-	fmt.Printf("offset %d dataSize %d\n", offset, dataSize)
-	fmt.Printf("read needle meta [%d,%d) size %d\n", startOffset, stopOffset, metaSize)
 	metaSlice := make([]byte, int(metaSize))
 
 	count, err = r.ReadAt(metaSlice, startOffset)

weed/storage/needle/needle_read_test.go

@@ -74,7 +74,7 @@ func TestPageRead(t *testing.T) {
 		fmt.Printf("Checksum value %d\n", checksumValue)
 
 		buf := make([]byte, 1024)
-		if err = n.ReadNeedleDataInto(datBackend, offset, buf, io.Discard, checksumValue); err != nil {
+		if err = n.ReadNeedleDataInto(datBackend, offset, buf, io.Discard, 0, int64(n.DataSize), checksumValue); err != nil {
 			t.Fatalf("ReadNeedleDataInto: %v", err)
 		}
 

weed/storage/store.go

@@ -2,6 +2,7 @@ package storage
 
 import (
 	"fmt"
+	"io"
 	"path/filepath"
 	"strings"
 	"sync/atomic"
@@ -26,7 +27,13 @@ const (
 )
 
 type ReadOption struct {
-	ReadDeleted bool
+	ReadDeleted     bool
+	AttemptMetaOnly bool
+	MustMetaOnly    bool
+	IsMetaOnly      bool   // read status
+	ChecksumValue   uint32 // read status
+	VolumeRevision  uint16
+	IsOutOfRange    bool // whether need to read over MaxPossibleVolumeSize
 }
 
 /*
@@ -375,6 +382,12 @@ func (s *Store) ReadVolumeNeedle(i needle.VolumeId, n *needle.Needle, readOption
 	}
 	return 0, fmt.Errorf("volume %d not found", i)
 }
+func (s *Store) ReadVolumeNeedleDataInto(i needle.VolumeId, n *needle.Needle, readOption *ReadOption, writer io.Writer, offset int64, size int64) error {
+	if v := s.findVolume(i); v != nil {
+		return v.readNeedleDataInto(n, readOption, writer, offset, size)
+	}
+	return fmt.Errorf("volume %d not found", i)
+}
 func (s *Store) GetVolume(i needle.VolumeId) *Volume {
 	return s.findVolume(i)
 }

weed/storage/volume_read.go

@@ -2,6 +2,7 @@ package storage
 
 import (
 	"fmt"
+	"github.com/chrislusf/seaweedfs/weed/util/mem"
 	"io"
 	"time"
 
@@ -12,8 +13,10 @@ import (
 	. "github.com/chrislusf/seaweedfs/weed/storage/types"
 )
 
+const PagedReadLimit = 1024 * 1024
+
 // read fills in Needle content by looking up n.Id from NeedleMapper
-func (v *Volume) readNeedle(n *needle.Needle, readOption *ReadOption, onReadSizeFn func(size Size)) (int, error) {
+func (v *Volume) readNeedle(n *needle.Needle, readOption *ReadOption, onReadSizeFn func(size Size)) (count int, err error) {
 	v.dataFileAccessLock.RLock()
 	defer v.dataFileAccessLock.RUnlock()
 
@@ -36,31 +39,84 @@ func (v *Volume) readNeedle(n *needle.Needle, readOption *ReadOption, onReadSize
 	if onReadSizeFn != nil {
 		onReadSizeFn(readSize)
 	}
-	err := n.ReadData(v.DataBackend, nv.Offset.ToActualOffset(), readSize, v.Version())
-	if err == needle.ErrorSizeMismatch && OffsetSize == 4 {
-		err = n.ReadData(v.DataBackend, nv.Offset.ToActualOffset()+int64(MaxPossibleVolumeSize), readSize, v.Version())
+	if readOption != nil && readOption.AttemptMetaOnly && readSize > PagedReadLimit {
+		readOption.VolumeRevision = v.SuperBlock.CompactionRevision
+		readOption.ChecksumValue, err = n.ReadNeedleMeta(v.DataBackend, nv.Offset.ToActualOffset(), readSize, v.Version())
+		if err == needle.ErrorSizeMismatch && OffsetSize == 4 {
+			readOption.IsOutOfRange = true
+			readOption.ChecksumValue, err = n.ReadNeedleMeta(v.DataBackend, nv.Offset.ToActualOffset()+int64(MaxPossibleVolumeSize), readSize, v.Version())
+		}
+		if err != nil {
+			return 0, err
+		}
+		if !n.IsCompressed() && !n.IsChunkedManifest() {
+			readOption.IsMetaOnly = true
+		}
 	}
-	v.checkReadWriteError(err)
-	if err != nil {
-		return 0, err
+	if readOption == nil || !readOption.IsMetaOnly {
+		err = n.ReadData(v.DataBackend, nv.Offset.ToActualOffset(), readSize, v.Version())
+		if err == needle.ErrorSizeMismatch && OffsetSize == 4 {
+			err = n.ReadData(v.DataBackend, nv.Offset.ToActualOffset()+int64(MaxPossibleVolumeSize), readSize, v.Version())
+		}
+		v.checkReadWriteError(err)
+		if err != nil {
+			return 0, err
+		}
 	}
-	bytesRead := len(n.Data)
+	count = int(n.DataSize)
 	if !n.HasTtl() {
-		return bytesRead, nil
+		return
 	}
 	ttlMinutes := n.Ttl.Minutes()
 	if ttlMinutes == 0 {
-		return bytesRead, nil
+		return
 	}
 	if !n.HasLastModifiedDate() {
-		return bytesRead, nil
+		return
 	}
 	if time.Now().Before(time.Unix(0, int64(n.AppendAtNs)).Add(time.Duration(ttlMinutes) * time.Minute)) {
-		return bytesRead, nil
+		return
 	}
 	return -1, ErrorNotFound
 }
 
+// read fills in Needle content by looking up n.Id from NeedleMapper
+func (v *Volume) readNeedleDataInto(n *needle.Needle, readOption *ReadOption, writer io.Writer, offset int64, size int64) (err error) {
+	v.dataFileAccessLock.RLock()
+	defer v.dataFileAccessLock.RUnlock()
+
+	nv, ok := v.nm.Get(n.Id)
+	if !ok || nv.Offset.IsZero() {
+		return ErrorNotFound
+	}
+	readSize := nv.Size
+	if readSize.IsDeleted() {
+		if readOption != nil && readOption.ReadDeleted && readSize != TombstoneFileSize {
+			glog.V(3).Infof("reading deleted %s", n.String())
+			readSize = -readSize
+		} else {
+			return ErrorDeleted
+		}
+	}
+	if readSize == 0 {
+		return nil
+	}
+
+	if readOption.VolumeRevision != v.SuperBlock.CompactionRevision {
+		// the volume is compacted
+		readOption.IsOutOfRange = false
+		readOption.ChecksumValue, err = n.ReadNeedleMeta(v.DataBackend, nv.Offset.ToActualOffset(), readSize, v.Version())
+	}
+	buf := mem.Allocate(1024 * 1024)
+	defer mem.Free(buf)
+	actualOffset := nv.Offset.ToActualOffset()
+	if readOption.IsOutOfRange {
+		actualOffset += int64(MaxPossibleVolumeSize)
+	}
+
+	return n.ReadNeedleDataInto(v.DataBackend, actualOffset, buf, writer, offset, size, readOption.ChecksumValue)
+}
+
 // read fills in Needle content by looking up n.Id from NeedleMapper
 func (v *Volume) ReadNeedleBlob(offset int64, size Size) ([]byte, error) {
 	v.dataFileAccessLock.RLock()