Storage: remove bufferedFileWriter (dead code)

Signed-off-by: Arthur Baars <arthur@semmle.com>

registry/storage/blobwriter.go

@@ -30,7 +30,7 @@ type blobWriter struct {
 
 	// implementes io.WriteSeeker, io.ReaderFrom and io.Closer to satisfy
 	// LayerUpload Interface
-	bufferedFileWriter
+	fileWriter
 
 	resumableDigestEnabled bool
 }
@@ -51,7 +51,7 @@ func (bw *blobWriter) StartedAt() time.Time {
 func (bw *blobWriter) Commit(ctx context.Context, desc distribution.Descriptor) (distribution.Descriptor, error) {
 	context.GetLogger(ctx).Debug("(*blobWriter).Commit")
 
-	if err := bw.bufferedFileWriter.Close(); err != nil {
+	if err := bw.fileWriter.Close(); err != nil {
 		return distribution.Descriptor{}, err
 	}
 
@@ -100,7 +100,7 @@ func (bw *blobWriter) Write(p []byte) (int, error) {
 		return 0, err
 	}
 
-	n, err := io.MultiWriter(&bw.bufferedFileWriter, bw.digester.Hash()).Write(p)
+	n, err := io.MultiWriter(&bw.fileWriter, bw.digester.Hash()).Write(p)
 	bw.written += int64(n)
 
 	return n, err
@@ -114,7 +114,7 @@ func (bw *blobWriter) ReadFrom(r io.Reader) (n int64, err error) {
 		return 0, err
 	}
 
-	nn, err := bw.bufferedFileWriter.ReadFrom(io.TeeReader(r, bw.digester.Hash()))
+	nn, err := bw.fileWriter.ReadFrom(io.TeeReader(r, bw.digester.Hash()))
 	bw.written += nn
 
 	return nn, err
@@ -129,7 +129,7 @@ func (bw *blobWriter) Close() error {
 		return err
 	}
 
-	return bw.bufferedFileWriter.Close()
+	return bw.fileWriter.Close()
 }
 
 // validateBlob checks the data against the digest, returning an error if it
@@ -149,7 +149,7 @@ func (bw *blobWriter) validateBlob(ctx context.Context, desc distribution.Descri
 	}
 
 	// Stat the on disk file
-	if fi, err := bw.bufferedFileWriter.driver.Stat(ctx, bw.path); err != nil {
+	if fi, err := bw.fileWriter.driver.Stat(ctx, bw.path); err != nil {
 		switch err := err.(type) {
 		case storagedriver.PathNotFoundError:
 			// NOTE(stevvooe): We really don't care if the file is
@@ -223,7 +223,7 @@ func (bw *blobWriter) validateBlob(ctx context.Context, desc distribution.Descri
 			}
 
 			// Read the file from the backend driver and validate it.
-			fr, err := newFileReader(ctx, bw.bufferedFileWriter.driver, bw.path, desc.Size)
+			fr, err := newFileReader(ctx, bw.fileWriter.driver, bw.path, desc.Size)
 			if err != nil {
 				return distribution.Descriptor{}, err
 			}
@@ -357,7 +357,7 @@ func (bw *blobWriter) Reader() (io.ReadCloser, error) {
 	// todo(richardscothern): Change to exponential backoff, i=0.5, e=2, n=4
 	try := 1
 	for try <= 5 {
-		_, err := bw.bufferedFileWriter.driver.Stat(bw.ctx, bw.path)
+		_, err := bw.fileWriter.driver.Stat(bw.ctx, bw.path)
 		if err == nil {
 			break
 		}
@@ -371,7 +371,7 @@ func (bw *blobWriter) Reader() (io.ReadCloser, error) {
 		}
 	}
 
-	readCloser, err := bw.bufferedFileWriter.driver.ReadStream(bw.ctx, bw.path, 0)
+	readCloser, err := bw.fileWriter.driver.ReadStream(bw.ctx, bw.path, 0)
 	if err != nil {
 		return nil, err
 	}

registry/storage/filewriter.go

@@ -1,7 +1,6 @@
 package storage
 
 import (
-	"bufio"
 	"bytes"
 	"fmt"
 	"io"
@@ -11,10 +10,6 @@ import (
 	storagedriver "github.com/docker/distribution/registry/storage/driver"
 )
 
-const (
-	fileWriterBufferSize = 5 << 20
-)
-
 // fileWriter implements a remote file writer backed by a storage driver.
 type fileWriter struct {
 	driver storagedriver.StorageDriver
@@ -30,11 +25,6 @@ type fileWriter struct {
 	err    error // terminal error, if set, reader is closed
 }
 
-type bufferedFileWriter struct {
-	fileWriter
-	bw *bufio.Writer
-}
-
 // fileWriterInterface makes the desired io compliant interface that the
 // filewriter should implement.
 type fileWriterInterface interface {
@@ -47,7 +37,7 @@ var _ fileWriterInterface = &fileWriter{}
 
 // newFileWriter returns a prepared fileWriter for the driver and path. This
 // could be considered similar to an "open" call on a regular filesystem.
-func newFileWriter(ctx context.Context, driver storagedriver.StorageDriver, path string) (*bufferedFileWriter, error) {
+func newFileWriter(ctx context.Context, driver storagedriver.StorageDriver, path string) (*fileWriter, error) {
 	fw := fileWriter{
 		driver: driver,
 		path:   path,
@@ -69,42 +59,7 @@ func newFileWriter(ctx context.Context, driver storagedriver.StorageDriver, path
 		fw.size = fi.Size()
 	}
 
-	buffered := bufferedFileWriter{
-		fileWriter: fw,
-	}
-	buffered.bw = bufio.NewWriterSize(&buffered.fileWriter, fileWriterBufferSize)
-
-	return &buffered, nil
-}
-
-// wraps the fileWriter.Write method to buffer small writes
-func (bfw *bufferedFileWriter) Write(p []byte) (int, error) {
-	return bfw.bw.Write(p)
-}
-
-// wraps fileWriter.Close to ensure the buffer is flushed
-// before we close the writer.
-func (bfw *bufferedFileWriter) Close() (err error) {
-	if err = bfw.Flush(); err != nil {
-		return err
-	}
-	err = bfw.fileWriter.Close()
-	return err
-}
-
-// wraps fileWriter.Seek to ensure offset is handled
-// correctly in respect to pending data in the buffer
-func (bfw *bufferedFileWriter) Seek(offset int64, whence int) (int64, error) {
-	if err := bfw.Flush(); err != nil {
-		return 0, err
-	}
-	return bfw.fileWriter.Seek(offset, whence)
-}
-
-// wraps bufio.Writer.Flush to allow intermediate flushes
-// of the bufferedFileWriter
-func (bfw *bufferedFileWriter) Flush() error {
-	return bfw.bw.Flush()
+	return &fw, nil
 }
 
 // Write writes the buffer p at the current write offset.

registry/storage/filewriter_test.go

@@ -45,7 +45,6 @@ func TestSimpleWrite(t *testing.T) {
 	if err != nil {
 		t.Fatalf("unexpected error writing content: %v", err)
 	}
-	fw.Flush()
 
 	if n != len(content) {
 		t.Fatalf("unexpected write length: %d != %d", n, len(content))
@@ -163,41 +162,6 @@ func TestSimpleWrite(t *testing.T) {
 	}
 }
 
-func TestBufferedFileWriter(t *testing.T) {
-	ctx := context.Background()
-	writer, err := newFileWriter(ctx, inmemory.New(), "/random")
-
-	if err != nil {
-		t.Fatalf("Failed to initialize bufferedFileWriter: %v", err.Error())
-	}
-
-	// write one byte and ensure the offset hasn't been incremented.
-	// offset will only get incremented when the buffer gets flushed
-	short := []byte{byte(1)}
-
-	writer.Write(short)
-
-	if writer.offset > 0 {
-		t.Fatalf("WriteStream called prematurely")
-	}
-
-	// write enough data to cause the buffer to flush and confirm
-	// the offset has been incremented
-	long := make([]byte, fileWriterBufferSize)
-	_, err = rand.Read(long)
-	if err != nil {
-		t.Fatalf("unexpected error building random data: %v", err)
-	}
-	for i := range long {
-		long[i] = byte(i)
-	}
-	writer.Write(long)
-	writer.Close()
-	if writer.offset != (fileWriterBufferSize + 1) {
-		t.Fatalf("WriteStream not called when buffer capacity reached")
-	}
-}
-
 func BenchmarkFileWriter(b *testing.B) {
 	b.StopTimer() // not sure how long setup above will take
 	for i := 0; i < b.N; i++ {
@@ -237,14 +201,14 @@ func BenchmarkFileWriter(b *testing.B) {
 	}
 }
 
-func BenchmarkBufferedFileWriter(b *testing.B) {
+func BenchmarkfileWriter(b *testing.B) {
 	b.StopTimer() // not sure how long setup above will take
 	ctx := context.Background()
 	for i := 0; i < b.N; i++ {
 		bfw, err := newFileWriter(ctx, inmemory.New(), "/random")
 
 		if err != nil {
-			b.Fatalf("Failed to initialize bufferedFileWriter: %v", err.Error())
+			b.Fatalf("Failed to initialize fileWriter: %v", err.Error())
 		}
 
 		randomBytes := make([]byte, 1<<20)

registry/storage/linkedblobstore.go

@@ -197,7 +197,7 @@ func (lbs *linkedBlobStore) newBlobUpload(ctx context.Context, uuid, path string
 		id:                     uuid,
 		startedAt:              startedAt,
 		digester:               digest.Canonical.New(),
-		bufferedFileWriter:     *fw,
+		fileWriter:             *fw,
 		resumableDigestEnabled: lbs.resumableDigestEnabled,
 	}