debugd: implement upload of multiple binaries

debugd/internal/filetransfer/streamer/streamer.go

@@ -0,0 +1,146 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package streamer
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"sync"
+
+	pb "github.com/edgelesssys/constellation/v2/debugd/service"
+	"github.com/schollz/progressbar/v3"
+	"github.com/spf13/afero"
+)
+
+// FileStreamer handles reading and writing of a file using a stream of chunks.
+type FileStreamer struct {
+	fs  afero.Fs
+	mux sync.RWMutex
+}
+
+// ReadChunkStream is abstraction over a gRPC stream that allows us to receive chunks via gRPC.
+type ReadChunkStream interface {
+	Recv() (*pb.Chunk, error)
+}
+
+// WriteChunkStream is abstraction over a gRPC stream that allows us to send chunks via gRPC.
+type WriteChunkStream interface {
+	Send(chunk *pb.Chunk) error
+}
+
+// New creates a new FileStreamer.
+func New(fs afero.Fs) *FileStreamer {
+	return &FileStreamer{
+		fs:  fs,
+		mux: sync.RWMutex{},
+	}
+}
+
+// WriteStream opens a file to write to and streams chunks from a gRPC stream into the file.
+func (f *FileStreamer) WriteStream(filename string, stream ReadChunkStream, showProgress bool) error {
+	f.mux.Lock()
+	defer f.mux.Unlock()
+	file, err := f.fs.OpenFile(filename, os.O_WRONLY|os.O_CREATE, os.ModePerm)
+	if err != nil {
+		return fmt.Errorf("open %v for writing: %w", filename, err)
+	}
+	defer file.Close()
+	stat, err := file.Stat()
+	if err != nil {
+		return fmt.Errorf("performing stat on %v to get the file size: %w", filename, err)
+	}
+
+	var bar *progressbar.ProgressBar
+	if showProgress {
+		bar = newProgressBar(stat.Size())
+		defer bar.Close()
+	}
+
+	return writeInner(file, stream, bar)
+}
+
+// ReadStream opens a file to read from and streams its contents chunkwise over gRPC.
+func (f *FileStreamer) ReadStream(filename string, stream WriteChunkStream, chunksize uint, showProgress bool) error {
+	if chunksize == 0 {
+		return errors.New("invalid chunksize")
+	}
+	// fail if file is currently RW locked
+	if f.mux.TryRLock() {
+		defer f.mux.RUnlock()
+	} else {
+		return errors.New("a file is opened for writing so cannot read at this time")
+	}
+	file, err := f.fs.OpenFile(filename, os.O_RDONLY, 0o755)
+	if err != nil {
+		return fmt.Errorf("open %v for reading: %w", filename, err)
+	}
+	defer file.Close()
+	stat, err := file.Stat()
+	if err != nil {
+		return fmt.Errorf("performing stat on %v to get the file size: %w", filename, err)
+	}
+
+	var bar *progressbar.ProgressBar
+	if showProgress {
+		bar = newProgressBar(stat.Size())
+		defer bar.Close()
+	}
+
+	return readInner(file, stream, chunksize, bar)
+}
+
+// readInner reads from a an io.Reader and sends chunks over a gRPC stream.
+func readInner(fp io.Reader, stream WriteChunkStream, chunksize uint, bar *progressbar.ProgressBar) error {
+	buf := make([]byte, chunksize)
+	for {
+		n, readErr := fp.Read(buf)
+		isLast := errors.Is(readErr, io.EOF)
+		if readErr != nil && !isLast {
+			return fmt.Errorf("reading file chunk: %w", readErr)
+		}
+		if err := stream.Send(&pb.Chunk{Content: buf[:n], Last: isLast}); err != nil {
+			return fmt.Errorf("sending chunk: %w", err)
+		}
+		if bar != nil {
+			_ = bar.Add(n)
+		}
+		if isLast {
+			return nil
+		}
+	}
+}
+
+// writeInner writes chunks from a gRPC stream to an io.Writer.
+func writeInner(fp io.Writer, stream ReadChunkStream, bar *progressbar.ProgressBar) error {
+	for {
+		chunk, recvErr := stream.Recv()
+		if recvErr != nil {
+			return fmt.Errorf("reading stream: %w", recvErr)
+		}
+		if _, err := fp.Write(chunk.Content); err != nil {
+			return fmt.Errorf("writing chunk to disk: %w", err)
+		}
+		if bar != nil {
+			_ = bar.Add(len(chunk.Content))
+		}
+		if chunk.Last {
+			return nil
+		}
+	}
+}
+
+// newProgressBar creates a new progress bar.
+func newProgressBar(size int64) *progressbar.ProgressBar {
+	return progressbar.NewOptions64(
+		size,
+		progressbar.OptionSetDescription("transferring file"),
+		progressbar.OptionShowBytes(true),
+		progressbar.OptionClearOnFinish(),
+	)
+}