feat: Add function that writes to a file without expanding the buffer and closes the file.

internal/bsr/bsr.go

@@ -657,7 +657,7 @@ func (c *Connection) NewMessagesWriter(ctx context.Context, dir Direction) (io.W
 }
 
 // NewRequestsWriter creates a writer for recording connection requests.
-func (c *Connection) NewRequestsWriter(ctx context.Context, dir Direction) (io.Writer, error) {
+func (c *Connection) NewRequestsWriter(ctx context.Context, dir Direction) (storage.Writer, error) {
 	const op = "bsr.(Connection).NewRequestsWriter"
 
 	switch {
@@ -704,7 +704,7 @@ func (c *Channel) Close(ctx context.Context) error {
 }
 
 // NewMessagesWriter creates a writer for recording channel messages.
-func (c *Channel) NewMessagesWriter(ctx context.Context, dir Direction) (io.Writer, error) {
+func (c *Channel) NewMessagesWriter(ctx context.Context, dir Direction) (storage.Writer, error) {
 	const op = "bsr.(Channel).NewMessagesWriter"
 
 	switch {
@@ -726,7 +726,7 @@ func (c *Channel) NewMessagesWriter(ctx context.Context, dir Direction) (io.Writ
 }
 
 // NewRequestsWriter creates a writer for recording channel requests.
-func (c *Channel) NewRequestsWriter(ctx context.Context, dir Direction) (io.Writer, error) {
+func (c *Channel) NewRequestsWriter(ctx context.Context, dir Direction) (storage.Writer, error) {
 	const op = "bsr.(Channel).NewRequestsWriter"
 
 	switch {

internal/bsr/convert/convert_test.go

@@ -16,6 +16,7 @@ import (
 	"github.com/hashicorp/boundary/internal/bsr/internal/fstest"
 	"github.com/hashicorp/boundary/internal/bsr/kms"
 	"github.com/hashicorp/boundary/internal/bsr/ssh"
+	"github.com/hashicorp/boundary/internal/storage"
 	"github.com/stretchr/testify/require"
 )
 
@@ -45,7 +46,7 @@ func testChunks(s string, d bsr.Direction, p bsr.Protocol) []bsr.Chunk {
 	}
 }
 
-func writeToChannels(ctx context.Context, w io.Writer, chunks ...bsr.Chunk) error {
+func writeToChannels(ctx context.Context, w storage.Writer, chunks ...bsr.Chunk) error {
 	w.Write(bsr.Magic.Bytes())
 	enc, err := bsr.NewChunkEncoder(ctx, w, bsr.NoCompression, bsr.NoEncryption)
 	if err != nil {

internal/bsr/convert/ssh_test.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/hashicorp/boundary/internal/bsr"
 	sshv1 "github.com/hashicorp/boundary/internal/bsr/gen/ssh/v1"
+	"github.com/hashicorp/boundary/internal/bsr/internal/fstest"
 	"github.com/hashicorp/boundary/internal/bsr/ssh"
 	"github.com/stretchr/testify/require"
 )
@@ -31,9 +32,10 @@ func Test_sshChannelToAsciicast(t *testing.T) {
 		return f
 	}
 	newScanner := func(chunks ...bsr.Chunk) *bsr.ChunkScanner {
-		var buf bytes.Buffer
+		buf, err := fstest.NewTempBuffer()
+		require.NoError(t, err)
 		buf.Write(bsr.Magic.Bytes())
-		enc, err := bsr.NewChunkEncoder(ctx, &buf, bsr.NoCompression, bsr.NoEncryption)
+		enc, err := bsr.NewChunkEncoder(ctx, buf, bsr.NoCompression, bsr.NoEncryption)
 		require.NoError(t, err)
 
 		for _, c := range chunks {

internal/bsr/encode.go

@@ -13,6 +13,8 @@ import (
 	"hash/crc32"
 	"io"
 	"sync"
+
+	"github.com/hashicorp/boundary/internal/storage"
 )
 
 type encodeCache struct {
@@ -43,13 +45,13 @@ var encodeCachePool = &sync.Pool{
 // ChunkEncoder will encode a chunk and write it to the writer.
 // It will compress the chunk data based on the compression.
 type ChunkEncoder struct {
-	w           io.Writer
+	w           storage.Writer
 	compression Compression
 	encryption  Encryption
 }
 
 // NewChunkEncoder creates a ChunkEncoder.
-func NewChunkEncoder(ctx context.Context, w io.Writer, c Compression, e Encryption) (*ChunkEncoder, error) {
+func NewChunkEncoder(ctx context.Context, w storage.Writer, c Compression, e Encryption) (*ChunkEncoder, error) {
 	const op = "bsr.NewChunkEncoder"
 
 	if w == nil {

internal/bsr/encode_bench_test.go

@@ -4,11 +4,12 @@
 package bsr
 
 import (
-	"bytes"
 	"context"
 	"fmt"
 	"testing"
 	"time"
+
+	"github.com/hashicorp/boundary/internal/bsr/internal/fstest"
 )
 
 type testChunk struct {
@@ -48,8 +49,11 @@ func BenchmarkEncodeParallel(b *testing.B) {
 		b.StartTimer()
 		b.RunParallel(func(pb *testing.PB) {
 			for pb.Next() {
-				var buf bytes.Buffer
-				enc, _ := NewChunkEncoder(ctx, &buf, NoCompression, NoEncryption)
+				buf, err := fstest.NewTempBuffer()
+				if err != nil {
+					panic("could not create buffer")
+				}
+				enc, _ := NewChunkEncoder(ctx, buf, NoCompression, NoEncryption)
 				for _, c := range chunks {
 					if _, err := enc.Encode(ctx, c); err != nil {
 						b.Fatal("Encode:", err)
@@ -75,8 +79,11 @@ func BenchmarkEncodeSequential(b *testing.B) {
 			b.StartTimer()
 
 			for i := 0; i < b.N; i++ {
-				var buf bytes.Buffer
-				enc, _ := NewChunkEncoder(ctx, &buf, NoCompression, NoEncryption)
+				buf, err := fstest.NewTempBuffer()
+				if err != nil {
+					panic("could not create buffer")
+				}
+				enc, _ := NewChunkEncoder(ctx, buf, NoCompression, NoEncryption)
 				for _, c := range chunks {
 					if _, err := enc.Encode(ctx, c); err != nil {
 						b.Fatal("Encode:", err)

internal/bsr/encode_test.go

@@ -9,11 +9,12 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"io"
 	"testing"
 	"time"
 
 	"github.com/hashicorp/boundary/internal/bsr"
+	"github.com/hashicorp/boundary/internal/bsr/internal/fstest"
+	"github.com/hashicorp/boundary/internal/storage"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -268,8 +269,9 @@ func TestChunkEncoder(t *testing.T) {
 
 	for _, tc := range cases {
 		t.Run(tc.name, func(t *testing.T) {
-			var buf bytes.Buffer
-			enc, err := bsr.NewChunkEncoder(ctx, &buf, tc.c, tc.e)
+			buf, err := fstest.NewTempBuffer()
+			require.NoError(t, err)
+			enc, err := bsr.NewChunkEncoder(ctx, buf, tc.c, tc.e)
 			require.NoError(t, err)
 
 			var wrote int
@@ -294,6 +296,10 @@ func (e errorWriter) Write(_ []byte) (int, error) {
 	return 0, fmt.Errorf("write error")
 }
 
+func (e errorWriter) WriteAndClose(_ []byte) (int, error) {
+	return 0, fmt.Errorf("write error")
+}
+
 func TestChunkEncoderEncodeError(t *testing.T) {
 	ctx := context.Background()
 
@@ -301,7 +307,7 @@ func TestChunkEncoderEncodeError(t *testing.T) {
 
 	cases := []struct {
 		name  string
-		w     io.Writer
+		w     storage.Writer
 		c     bsr.Compression
 		e     bsr.Encryption
 		chunk bsr.Chunk
@@ -309,7 +315,11 @@ func TestChunkEncoderEncodeError(t *testing.T) {
 	}{
 		{
 			"chunk-marshal-error",
-			func() io.Writer { var buf bytes.Buffer; return &buf }(),
+			func() storage.Writer {
+				buf, err := fstest.NewTempBuffer()
+				require.NoError(t, err)
+				return buf
+			}(),
 			bsr.NoCompression,
 			bsr.NoEncryption,
 			&testChunk{
@@ -325,7 +335,7 @@ func TestChunkEncoderEncodeError(t *testing.T) {
 		},
 		{
 			"writer-error",
-			func() io.Writer { return errorWriter{} }(),
+			func() storage.Writer { return errorWriter{} }(),
 			bsr.NoCompression,
 			bsr.NoEncryption,
 			&testChunk{
@@ -357,21 +367,29 @@ func TestChunkEncoderErrors(t *testing.T) {
 
 	cases := []struct {
 		name string
-		w    io.Writer
+		w    storage.Writer
 		c    bsr.Compression
 		e    bsr.Encryption
 		want error
 	}{
 		{
 			"invalid-compression",
-			func() io.Writer { var buf bytes.Buffer; return &buf }(),
+			func() storage.Writer {
+				buf, err := fstest.NewTempBuffer()
+				require.NoError(t, err)
+				return buf
+			}(),
 			bsr.Compression(255),
 			bsr.NoEncryption,
 			errors.New("bsr.NewChunkEncoder: invalid compression: invalid parameter"),
 		},
 		{
 			"invalid-encryption",
-			func() io.Writer { var buf bytes.Buffer; return &buf }(),
+			func() storage.Writer {
+				buf, err := fstest.NewTempBuffer()
+				require.NoError(t, err)
+				return buf
+			}(),
 			bsr.NoCompression,
 			bsr.Encryption(255),
 			errors.New("bsr.NewChunkEncoder: invalid encryption: invalid parameter"),

internal/bsr/internal/checksum/checksum.go

@@ -29,6 +29,12 @@ type writerFile interface {
 	fs.File
 	io.WriteCloser
 	io.StringWriter
+	WriteAndClose([]byte) (int, error)
+}
+
+type underlyingFile interface {
+	fs.File
+	WriteAndClose([]byte) (int, error)
 }
 
 // File is a writable file that will compute its checksum while it is written
@@ -45,7 +51,7 @@ type File struct {
 
 	checksumWriter io.Writer
 
-	underlying fs.File
+	underlying underlyingFile
 }
 
 // NewFile wraps the provided writerFile in a checksumed File. When the file is
@@ -113,4 +119,36 @@ func (f *File) Close() error {
 	return closeErrors
 }
 
+// WriteAndClose writes to the underlying file, closes the Sha256SumWriter
+// and computes the checksum and writes it to f.checksumWriter
+func (f *File) WriteAndClose(b []byte) (int, error) {
+	const op = "checksum.(File).WriteAndClose"
+
+	var closeErrors error
+
+	// Call stat before closure; calling it after results in an err
+	s, err := f.Stat()
+	if err != nil {
+		closeErrors = errors.Join(closeErrors, fmt.Errorf("%s: %w", op, err))
+		return 0, closeErrors
+	}
+
+	n, err := f.underlying.WriteAndClose(b)
+	if err != nil {
+		return 0, fmt.Errorf("%s: %w", op, err)
+	}
+
+	sum, err := f.Sha256SumWriter.Sum(f.ctx, crypto.WithHexEncoding(true))
+	if err != nil {
+		closeErrors = errors.Join(closeErrors, fmt.Errorf("%s: %w", op, err))
+		return 0, closeErrors
+	}
+
+	if _, err := f.checksumWriter.Write([]byte(fmt.Sprintf(checksumLine, sum, s.Name()))); err != nil {
+		closeErrors = errors.Join(closeErrors, fmt.Errorf("%s: %w", op, err))
+	}
+
+	return n, closeErrors
+}
+
 var _ writerFile = (*File)(nil)

internal/bsr/internal/fstest/fs.go

@@ -268,6 +268,11 @@ type MemFile struct {
 	syncMode   storage.SyncMode
 	accessMode storage.AccessMode
 
+	bufferSize        uint64
+	minimumBufferSize uint64
+	bufferOffset      int64
+	currentOffset     int64
+
 	sync.RWMutex
 }
 
@@ -287,6 +292,10 @@ func NewMemFile(n string, mode sfs.FileMode, options ...Option) *MemFile {
 		syncMode:          storageOpts.WithCloseSyncMode,
 		statFunc:          opts.withStatFunc,
 		closeFunc:         opts.withCloseFunc,
+		bufferSize:        storageOpts.WithBuffer,
+		minimumBufferSize: storageOpts.WithMinimumBuffer,
+		currentOffset:     0,
+		bufferOffset:      0,
 	}
 }
 
@@ -347,6 +356,10 @@ func (m *MemFile) Close() error {
 	m.Lock()
 	defer m.Unlock()
 
+	return m.close()
+}
+
+func (m *MemFile) close() error {
 	if m.Closed {
 		return fmt.Errorf("close on closed file")
 	}
@@ -367,6 +380,10 @@ func (m *MemFile) Write(p []byte) (n int, err error) {
 	m.Lock()
 	defer m.Unlock()
 
+	return m.write(p)
+}
+
+func (m *MemFile) write(p []byte) (n int, err error) {
 	if m.Closed {
 		return 0, fmt.Errorf("write on closed file")
 	}
@@ -385,6 +402,24 @@ func (m *MemFile) Write(p []byte) (n int, err error) {
 	return m.Buf.Write(p)
 }
 
+// WriteAndClose writes and closes the file.
+func (m *MemFile) WriteAndClose(p []byte) (int, error) {
+	m.Lock()
+	defer m.Unlock()
+
+	n, err := m.write(p)
+	if err != nil {
+		return n, fmt.Errorf("write failed: %w", err)
+	}
+
+	err = m.close()
+	if err != nil {
+		return n, fmt.Errorf("close failed: %w", err)
+	}
+
+	return n, nil
+}
+
 // TempFile implements storage.TempFile
 type TempFile struct {
 	*os.File
@@ -412,3 +447,24 @@ func (t *TempFile) Close() error {
 	}
 	return os.Remove(fname.Name())
 }
+
+func (t *TempFile) WriteAndClose(b []byte) (int, error) {
+	panic("not implemented")
+}
+
+type TempBuffer struct {
+	bytes.Buffer
+}
+
+// NewTempBuffer creates a TempBuffer.
+func NewTempBuffer() (*TempBuffer, error) {
+	var testBuffer bytes.Buffer
+	return &TempBuffer{
+		testBuffer,
+	}, nil
+}
+
+// WriteAndClose writes and closes the file.
+func (t *TempBuffer) WriteAndClose(b []byte) (int, error) {
+	return t.Write(b)
+}

internal/bsr/internal/fstest/fs_test.go

@@ -628,3 +628,28 @@ func TestOutOfSpace(t *testing.T) {
 	require.ErrorIs(t, err, fstest.ErrOutOfSpace)
 	assert.Nil(t, r2)
 }
+
+func TestMemFile_WriteAndClose(t *testing.T) {
+	mf := fstest.NewMemFile(
+		"test-write-and-close-file",
+		0o644,
+		fstest.WithStorageOptions([]storage.Option{
+			storage.WithFileAccessMode(storage.ReadWrite),
+		}))
+	require.False(t, mf.Closed, "MemFile is closed")
+
+	str1 := "Input 1"
+	n, err := mf.Write([]byte(str1))
+	require.NoError(t, err)
+	assert.NotNil(t, n)
+
+	str2 := "Input 2"
+	n, err = mf.WriteAndClose([]byte(str2))
+	require.NoError(t, err)
+	assert.NotNil(t, n)
+
+	expectedString := "Input 1Input 2"
+	assert.Equal(t, expectedString, mf.Buf.String())
+
+	require.True(t, mf.Closed, "MemFile is not closed")
+}

internal/bsr/internal/fstest/local.go

@@ -314,9 +314,15 @@ func (f *LocalFile) Read(b []byte) (int, error) {
 
 // Close closes the file preventing reads or writes.
 func (f *LocalFile) Close() error {
-	const op = "fstest.(LocalFile).Stat"
 	f.Lock()
 	defer f.Unlock()
+
+	return f.close()
+}
+
+func (f *LocalFile) close() error {
+	const op = "fstest.(LocalFile).close"
+
 	if f.closed {
 		return nil
 	}
@@ -330,9 +336,15 @@ func (f *LocalFile) Close() error {
 }
 
 func (f *LocalFile) Write(b []byte) (int, error) {
-	const op = "fstest.(localFile).Write"
 	f.Lock()
 	defer f.Unlock()
+
+	return f.write(b)
+}
+
+func (f *LocalFile) write(b []byte) (int, error) {
+	const op = "fstest.(localFile).write"
+
 	if f.closed {
 		return 0, fmt.Errorf("%s: file is closed", op)
 	}
@@ -352,3 +364,21 @@ func (f *LocalFile) WriteString(s string) (int, error) {
 	const op = "storage.(localFile).WriteString"
 	return f.Write([]byte(s))
 }
+
+// WriteAndClose writes and closes the file.
+func (f *LocalFile) WriteAndClose(b []byte) (int, error) {
+	f.Lock()
+	defer f.Unlock()
+
+	n, err := f.write(b)
+	if err != nil {
+		return n, fmt.Errorf("write failed: %w", err)
+	}
+
+	err = f.close()
+	if err != nil {
+		return n, fmt.Errorf("close failed: %w", err)
+	}
+
+	return n, nil
+}

internal/bsr/internal/journal/journal.go

@@ -20,6 +20,7 @@ type writerFile interface {
 	fs.File
 	io.WriteCloser
 	io.StringWriter
+	WriteAndClose([]byte) (int, error)
 }
 
 // Journal is used to record meta data about the operations that will be and
@@ -61,6 +62,11 @@ func (j *Journal) Record(op, f string) error {
 	return err
 }
 
+// WriteAndClose writes and closes the journal
+func (j *Journal) WriteAndClose(b []byte) (int, error) {
+	panic("not implemented")
+}
+
 // File is a writable file that will update a Journal as it closed.
 type File struct {
 	j *Journal
@@ -102,4 +108,30 @@ func (f *File) Close() error {
 	return f.j.Record("CLOSED", s.Name())
 }
 
+// WriteAndClose writes to the underlying file and closes the underlying file,
+// writing to the journal prior to and after
+func (f *File) WriteAndClose(b []byte) (int, error) {
+	const op = "journal.(File).Close"
+
+	s, err := f.Stat()
+	if err != nil {
+		return 0, fmt.Errorf("%s: %w", op, err)
+	}
+
+	if err := f.j.Record("CLOSING", s.Name()); err != nil {
+		return 0, fmt.Errorf("%s: %w", op, err)
+	}
+
+	n, err := f.writerFile.WriteAndClose(b)
+	if err != nil {
+		return n, fmt.Errorf("%s: %w", op, err)
+	}
+
+	if err := f.j.Record("CLOSED", s.Name()); err != nil {
+		return n, fmt.Errorf("%s: %w", op, err)
+	}
+
+	return n, err
+}
+
 var _ writerFile = (*File)(nil)

internal/storage/storage.go

@@ -55,8 +55,8 @@ type Container interface {
 // File represents a storage File.
 type File interface {
 	fs.File
-	io.Writer
 	io.StringWriter
+	Writer
 }
 
 // TempFile is a temporary File. It will get removed when Closed.
@@ -64,3 +64,11 @@ type TempFile interface {
 	File
 	io.Seeker
 }
+
+// Writer is an interface that extends the io.Writer interface with an additional
+// WriteAndClose method. WriteAndClose writes a byte slice and closes the file in
+// a single call.
+type Writer interface {
+	io.Writer
+	WriteAndClose([]byte) (int, error)
+}