shell: add volume.check.disk to fix inconsistency for replicated volumes

fix https://github.com/chrislusf/seaweedfs/issues/1923

weed/storage/needle/needle_read_write.go

@@ -3,13 +3,12 @@ package needle
 import (
 	"errors"
 	"fmt"
-	"io"
-	"math"
-
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/storage/backend"
 	. "github.com/chrislusf/seaweedfs/weed/storage/types"
 	"github.com/chrislusf/seaweedfs/weed/util"
+	"io"
+	"math"
 )
 
 const (
@@ -156,6 +155,35 @@ func (n *Needle) Append(w backend.BackendStorageFile, version Version) (offset u
 	return offset, size, actualSize, err
 }
 
+func WriteNeedleBlob(w backend.BackendStorageFile, dataSlice []byte, size Size, appendAtNs uint64, version Version) (offset uint64, err error) {
+
+	if end, _, e := w.GetStat(); e == nil {
+		defer func(w backend.BackendStorageFile, off int64) {
+			if err != nil {
+				if te := w.Truncate(end); te != nil {
+					glog.V(0).Infof("Failed to truncate %s back to %d with error: %v", w.Name(), end, te)
+				}
+			}
+		}(w, end)
+		offset = uint64(end)
+	} else {
+		err = fmt.Errorf("Cannot Read Current Volume Position: %v", e)
+		return
+	}
+
+	if version == Version3 {
+		tsOffset := NeedleHeaderSize + size + NeedleChecksumSize
+		util.Uint64toBytes(dataSlice[tsOffset : tsOffset+TimestampSize], appendAtNs)
+	}
+
+	if err == nil {
+		_, err = w.WriteAt(dataSlice, int64(offset))
+	}
+
+	return
+
+}
+
 func ReadNeedleBlob(r backend.BackendStorageFile, offset int64, size Size, version Version) (dataSlice []byte, err error) {
 
 	dataSize := GetActualSize(size, version)

weed/storage/needle_map/memdb.go

@@ -2,6 +2,7 @@ package needle_map
 
 import (
 	"fmt"
+	"io"
 	"os"
 
 	"github.com/syndtr/goleveldb/leveldb"
@@ -104,7 +105,13 @@ func (cm *MemDb) LoadFromIdx(idxName string) (ret error) {
 	}
 	defer idxFile.Close()
 
-	return idx.WalkIndexFile(idxFile, func(key NeedleId, offset Offset, size Size) error {
+	return cm.LoadFromReaderAt(idxFile)
+
+}
+
+func (cm *MemDb) LoadFromReaderAt(readerAt io.ReaderAt) (ret error) {
+
+	return idx.WalkIndexFile(readerAt, func(key NeedleId, offset Offset, size Size) error {
 		if offset.IsZero() || size.IsDeleted() {
 			return cm.Delete(key)
 		}

weed/storage/volume_read.go

@@ -58,6 +58,14 @@ func (v *Volume) readNeedle(n *needle.Needle, readOption *ReadOption) (int, erro
 	return -1, ErrorNotFound
 }
 
+// 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()
+	defer v.dataFileAccessLock.RUnlock()
+
+	return needle.ReadNeedleBlob(v.DataBackend, offset, size, v.Version())
+}
+
 type VolumeFileScanner interface {
 	VisitSuperBlock(super_block.SuperBlock) error
 	ReadNeedleBody() bool

weed/storage/volume_write.go

@@ -299,3 +299,29 @@ func (v *Volume) startWorker() {
 		}
 	}()
 }
+
+func (v *Volume) WriteNeedleBlob(needleId NeedleId, needleBlob []byte, size Size) error {
+
+	v.dataFileAccessLock.Lock()
+	defer v.dataFileAccessLock.Unlock()
+
+	if MaxPossibleVolumeSize < v.nm.ContentSize()+uint64(len(needleBlob)) {
+		return fmt.Errorf("volume size limit %d exceeded! current size is %d", MaxPossibleVolumeSize, v.nm.ContentSize())
+	}
+
+	appendAtNs := uint64(time.Now().UnixNano())
+	offset, err := needle.WriteNeedleBlob(v.DataBackend, needleBlob, size, appendAtNs, v.Version())
+
+	v.checkReadWriteError(err)
+	if err != nil {
+		return err
+	}
+	v.lastAppendAtNs = appendAtNs
+
+	// add to needle map
+	if err = v.nm.Put(needleId, ToOffset(int64(offset)), size); err != nil {
+		glog.V(4).Infof("failed to put in needle map %d: %v", needleId, err)
+	}
+
+	return err
+}