valsep: do not embed sstable.Writer methods on SSTBlobWriter

Instead, users of SSTBlobwriter will need to  explicitly access the SST writer
for any methods not redefined by SSTBlobWriter.  This prevents any confusion on
  whether values may be separated by the wrapper.

Author: xinhaoz

valsep/sst_blob_writer.go

@@ -19,10 +19,9 @@ import (
 // neverSeparateValues, this behaves like sstable.Writer and no blob
 // files are written.
 type SSTBlobWriter struct {
-	// Promote methods from sstable.Writer.
-	*sstable.Writer
-	valSep ValueSeparation
-	err    error
+	SSTWriter *sstable.Writer
+	valSep    ValueSeparation
+	err       error
 
 	blobFileNum base.DiskFileNum
 	closed      bool
@@ -76,7 +75,7 @@ func NewSSTBlobWriter(sstHandle objstorage.Writable, opts SSTBlobWriterOptions)
 		opts.SSTWriterOpts.Compression = block.FastestCompression
 	}
 
-	writer.Writer = sstable.NewWriter(sstHandle, opts.SSTWriterOpts)
+	writer.SSTWriter = sstable.NewWriter(sstHandle, opts.SSTWriterOpts)
 
 	// Create the value separator.
 	minimumValueSize := opts.ValueSeparationMinSize
@@ -123,7 +122,7 @@ func NewSSTBlobWriter(sstHandle objstorage.Writable, opts SSTBlobWriterOptions)
 
 // Error returns the current accumulated error if any.
 func (w *SSTBlobWriter) Error() error {
-	return errors.CombineErrors(w.err, w.Writer.Error())
+	return errors.CombineErrors(w.err, w.SSTWriter.Error())
 }
 
 // Set sets the value for the given key. The sequence number is set to 0.
@@ -142,8 +141,8 @@ func (w *SSTBlobWriter) Set(key, value []byte) error {
 
 	w.kvScratch.K = base.MakeInternalKey(key, 0, sstable.InternalKeyKindSet)
 	w.kvScratch.V = base.MakeInPlaceValue(value)
-	isLikelyMVCCGarbage := w.Raw().IsLikelyMVCCGarbage(w.kvScratch.K.UserKey, w.kvScratch.Kind())
-	return w.valSep.Add(w.Raw(), &w.kvScratch, false, isLikelyMVCCGarbage)
+	isLikelyMVCCGarbage := w.SSTWriter.Raw().IsLikelyMVCCGarbage(w.kvScratch.K.UserKey, w.kvScratch.Kind())
+	return w.valSep.Add(w.SSTWriter.Raw(), &w.kvScratch, false, isLikelyMVCCGarbage)
 }
 
 // BlobWriterMetas returns a slice of blob.FileWriterStats describing the
@@ -160,7 +159,7 @@ func (w *SSTBlobWriter) BlobWriterMetas() ([]blob.FileWriterStats, error) {
 
 // Close closes both the sstable writer and the blob file writer if any.
 func (w *SSTBlobWriter) Close() error {
-	w.err = errors.CombineErrors(w.err, w.Writer.Close())
+	w.err = errors.CombineErrors(w.err, w.SSTWriter.Close())
 	meta, err := w.valSep.FinishOutput()
 	if err != nil {
 		w.err = errors.CombineErrors(w.err, err)

valsep/sst_blob_writer_test.go

@@ -119,27 +119,27 @@ func runDataDriven(t *testing.T, file string) {
 						return fmt.Sprintf("error putting key %s: %v", kv.Key.UserKey, err)
 					}
 				case sstable.InternalKeyKindDelete, sstable.InternalKeyKindDeleteSized:
-					if err := writer.Delete(kv.Key.UserKey); err != nil {
+					if err := writer.SSTWriter.Delete(kv.Key.UserKey); err != nil {
 						return fmt.Sprintf("error deleting key %s: %v", kv.Key.UserKey, err)
 					}
 				case base.InternalKeyKindRangeDelete:
-					if err := writer.DeleteRange(kv.Span.Start, kv.Span.End); err != nil {
+					if err := writer.SSTWriter.DeleteRange(kv.Span.Start, kv.Span.End); err != nil {
 						return fmt.Sprintf("error deleting range %s-%s: %v", kv.Span.Start, kv.Span.End, err)
 					}
 				case sstable.InternalKeyKindMerge:
-					if err := writer.Merge(kv.Key.UserKey, kv.Value); err != nil {
+					if err := writer.SSTWriter.Merge(kv.Key.UserKey, kv.Value); err != nil {
 						return fmt.Sprintf("error merging key %s: %v", kv.Key.UserKey, err)
 					}
 				case base.InternalKeyKindRangeKeySet:
-					if err := writer.RangeKeySet(kv.Span.Start, kv.Span.End, nil, kv.Value); err != nil {
+					if err := writer.SSTWriter.RangeKeySet(kv.Span.Start, kv.Span.End, nil, kv.Value); err != nil {
 						return fmt.Sprintf("error setting range key %s-%s: %v", kv.Span.Start, kv.Span.End, err)
 					}
 				case base.InternalKeyKindRangeKeyUnset:
-					if err := writer.RangeKeyUnset(kv.Span.Start, kv.Span.End, kv.Key.UserKey); err != nil {
+					if err := writer.SSTWriter.RangeKeyUnset(kv.Span.Start, kv.Span.End, kv.Key.UserKey); err != nil {
 						return fmt.Sprintf("error unsetting range key %s-%s: %v", kv.Span.Start, kv.Span.End, err)
 					}
 				case base.InternalKeyKindRangeKeyDelete:
-					if err := writer.RangeKeyDelete(kv.Span.Start, kv.Span.End); err != nil {
+					if err := writer.SSTWriter.RangeKeyDelete(kv.Span.Start, kv.Span.End); err != nil {
 						return fmt.Sprintf("error deleting range key %s-%s: %v", kv.Span.Start, kv.Span.End, err)
 					}
 				default:
@@ -151,7 +151,7 @@ func runDataDriven(t *testing.T, file string) {
 				return fmt.Sprintf("error closing writer: %v", err)
 			}
 
-			tableMeta, err := writer.Metadata()
+			tableMeta, err := writer.SSTWriter.Metadata()
 			if err != nil {
 				return fmt.Sprintf("error getting metadata: %v", err)
 			}