1 files changed, 90 insertions, 4 deletions
diff --git a/weed/storage/needle/needle_read_options.go b/weed/storage/needle/needle_read_options.go
index 6ddc2d88e..77f0f26b8 100644
--- a/weed/storage/needle/needle_read_options.go
+++ b/weed/storage/needle/needle_read_options.go
@@ -1,8 +1,11 @@
 package needle
 
 import (
+	"io"
+
 	"github.com/seaweedfs/seaweedfs/weed/storage/backend"
 	. "github.com/seaweedfs/seaweedfs/weed/storage/types"
+	"github.com/seaweedfs/seaweedfs/weed/util"
 )
 
 // NeedleReadOptions specifies which parts of the Needle to read.
@@ -13,11 +16,94 @@ type NeedleReadOptions struct {
 }
 
 // ReadFromFile reads the Needle from the backend file according to the specified options.
-// For now, this is equivalent to ReadData (reads everything).
+// - If only ReadHeader is true, only the header is read and parsed.
+// - If ReadData or ReadMeta is true, reads GetActualSize(size, version) bytes from disk (size is the logical body size).
 func (n *Needle) ReadFromFile(r backend.BackendStorageFile, offset int64, size Size, version Version, opts NeedleReadOptions) error {
-	// Always read header and body for now (full read)
-	bytes, err := ReadNeedleBlob(r, offset, size, version)
-	if err != nil {
+	if opts.ReadHeader && !opts.ReadData && !opts.ReadMeta {
+		// Only read the header
+		header := make([]byte, NeedleHeaderSize)
+		count, err := r.ReadAt(header, offset)
+		if err == io.EOF && count == NeedleHeaderSize {
+			err = nil
+		}
+		if count != NeedleHeaderSize || err != nil {
+			return err
+		}
+		n.ParseNeedleHeader(header)
+		return nil
+	}
+	if opts.ReadHeader && opts.ReadMeta && !opts.ReadData {
+		// Read header first
+		header := make([]byte, NeedleHeaderSize)
+		count, err := r.ReadAt(header, offset)
+		if err == io.EOF && count == NeedleHeaderSize {
+			err = nil
+		}
+		if count != NeedleHeaderSize || err != nil {
+			return err
+		}
+		n.ParseNeedleHeader(header)
+
+		// Now read meta fields after DataSize+Data
+		metaOffset := offset + int64(NeedleHeaderSize)
+		metaIndex := 0
+		if version == Version2 || version == Version3 {
+			// Read DataSize to know how much to skip
+			dsBuf := make([]byte, 4)
+			count, err := r.ReadAt(dsBuf, metaOffset)
+			if err == io.EOF && count == 4 {
+				err = nil
+			}
+			if count != 4 || err != nil {
+				return err
+			}
+			dataSize := int(util.BytesToUint32(dsBuf))
+			metaIndex = 4 + dataSize
+			// Read meta fields (Flags, Name, Mime, etc.)
+			metaFieldsLen := int(n.Size) - dataSize // upper bound, may be more than needed
+			metaFieldsBuf := make([]byte, metaFieldsLen)
+			count, err = r.ReadAt(metaFieldsBuf, metaOffset+int64(metaIndex))
+			if err == io.EOF && count == metaFieldsLen {
+				err = nil
+			}
+			if count <= 0 || err != nil {
+				return err
+			}
+			_, err = n.readNeedleDataVersion2NonData(metaFieldsBuf)
+			if err != nil {
+				return err
+			}
+			// Now read checksum and (for v3) appendAtNs at the end
+			endMetaOffset := offset + int64(NeedleHeaderSize) + int64(n.Size)
+			endMetaLen := NeedleChecksumSize
+			if version == Version3 {
+				endMetaLen += TimestampSize
+			}
+			endMetaBuf := make([]byte, endMetaLen)
+			count, err = r.ReadAt(endMetaBuf, endMetaOffset)
+			if err == io.EOF && count == endMetaLen {
+				err = nil
+			}
+			if count != endMetaLen || err != nil {
+				return err
+			}
+			n.Checksum = CRC(util.BytesToUint32(endMetaBuf[:NeedleChecksumSize]))
+			if version == Version3 {
+				n.AppendAtNs = util.BytesToUint64(endMetaBuf[NeedleChecksumSize : NeedleChecksumSize+TimestampSize])
+			}
+			return nil
+		}
+		// For v1, just skip Data
+		return nil
+	}
+	// Otherwise, read the full on-disk entry size
+	readLen := int(GetActualSize(size, version))
+	bytes := make([]byte, readLen)
+	count, err := r.ReadAt(bytes, offset)
+	if err == io.EOF && count == readLen {
+		err = nil
+	}
+	if count != readLen || err != nil {
 		return err
 	}
 	return n.ReadBytes(bytes, offset, size, version)