[bug] - Handle empty reader case in newFileReader (#2854)

* Correclty handle empty files

* fix

* fix test

pkg/handlers/archive.go

@@ -21,7 +21,7 @@ const (
 
 var (
 	maxDepth   = 5
-	maxSize    = 250 * 1024 * 1024 // 250 MB
+	maxSize    = 2 << 30 // 2 GB
 	maxTimeout = time.Duration(30) * time.Second
 )
 
@@ -101,6 +101,10 @@ func (h *archiveHandler) openArchive(ctx logContext.Context, depth int, reader f
 
 		rdr, err := newFileReader(compReader)
 		if err != nil {
+			if errors.Is(err, ErrEmptyReader) {
+				ctx.Logger().V(5).Info("empty reader, skipping file")
+				return nil
+			}
 			return fmt.Errorf("error creating custom reader: %w", err)
 		}
 		defer rdr.Close()
@@ -146,7 +150,8 @@ func (h *archiveHandler) extractorHandler(archiveChan chan []byte) func(context.
 
 		fileSize := file.Size()
 		if int(fileSize) > maxSize {
-			lCtx.Logger().V(3).Info("skipping file due to size")
+			lCtx.Logger().V(3).Info("skipping file due to size", "size", fileSize)
+			h.metrics.incFilesSkipped()
 			return nil
 		}
 
@@ -180,6 +185,10 @@ func (h *archiveHandler) extractorHandler(archiveChan chan []byte) func(context.
 
 		rdr, err := newFileReader(f)
 		if err != nil {
+			if errors.Is(err, ErrEmptyReader) {
+				lCtx.Logger().V(5).Info("empty reader, skipping file")
+				return nil
+			}
 			return fmt.Errorf("error creating custom reader: %w", err)
 		}
 		defer rdr.Close()

pkg/handlers/handlers.go

@@ -35,6 +35,8 @@ type fileReader struct {
 	isGenericArchive bool
 }
 
+var ErrEmptyReader = errors.New("reader is empty")
+
 func newFileReader(r io.ReadCloser) (fileReader, error) {
 	defer r.Close()
 
@@ -57,6 +59,11 @@ func newFileReader(r io.ReadCloser) (fileReader, error) {
 		}
 	}()
 
+	// Check if the reader is empty.
+	if rdr.Size() == 0 {
+		return reader, ErrEmptyReader
+	}
+
 	format, arReader, err := archiver.Identify("", rdr)
 	switch {
 	case err == nil: // Archive detected
@@ -172,6 +179,10 @@ func HandleFile(
 
 	rdr, err := newFileReader(reader)
 	if err != nil {
+		if errors.Is(err, ErrEmptyReader) {
+			ctx.Logger().V(5).Info("empty reader, skipping file")
+			return nil
+		}
 		return fmt.Errorf("error creating custom reader: %w", err)
 	}
 	defer rdr.Close()

pkg/handlers/handlers_test.go

@@ -215,3 +215,22 @@ func TestHandleFileNonArchive(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, wantChunkCount, len(reporter.Ch))
 }
+
+func TestExtractTarContentWithEmptyFile(t *testing.T) {
+	file, err := os.Open("testdata/testdir.zip")
+	assert.Nil(t, err)
+
+	chunkCh := make(chan *sources.Chunk)
+	go func() {
+		defer close(chunkCh)
+		err := HandleFile(logContext.Background(), file, &sources.Chunk{}, sources.ChanReporter{Ch: chunkCh})
+		assert.NoError(t, err)
+	}()
+
+	wantCount := 4
+	count := 0
+	for range chunkCh {
+		count++
+	}
+	assert.Equal(t, wantCount, count)
+}

pkg/readers/bufferedfilereader.go

@@ -79,3 +79,6 @@ func (b *BufferedFileReader) ReadAt(p []byte, off int64) (n int, err error) {
 	}
 	return b.reader.Read(p)
 }
+
+// Size returns the total size of the data stored in the BufferedFileReader.
+func (b *BufferedFileReader) Size() int { return b.bufWriter.Len() }

pkg/writers/buffered_file_writer/bufferedfilewriter.go

@@ -84,14 +84,10 @@ func New(opts ...Option) *BufferedFileWriter {
 // NewFromReader creates a new instance of BufferedFileWriter and writes the content from the provided reader to the writer.
 func NewFromReader(r io.Reader, opts ...Option) (*BufferedFileWriter, error) {
 	writer := New(opts...)
-	if _, err := io.Copy(writer, r); err != nil {
+	if _, err := io.Copy(writer, r); err != nil && !errors.Is(err, io.EOF) {
 		return nil, fmt.Errorf("error writing to buffered file writer: %w", err)
 	}
 
-	if writer.buf == nil {
-		return nil, fmt.Errorf("reader was empty; no data written to buffered file writer")
-	}
-
 	return writer, nil
 }
 
@@ -271,7 +267,7 @@ func (w *BufferedFileWriter) ReadSeekCloser() (io.ReadSeekCloser, error) {
 	}
 
 	if w.buf == nil {
-		return nil, fmt.Errorf("BufferedFileWriter has not buffer data to read")
+		return nil, nil
 	}
 
 	// Data is in memory.

pkg/writers/buffered_file_writer/bufferedfilewriter_test.go

@@ -518,9 +518,8 @@ func TestNewFromReader(t *testing.T) {
 			wantData: "hello world",
 		},
 		{
-			name:    "Empty reader",
-			reader:  strings.NewReader(""),
-			wantErr: true,
+			name:   "Empty reader",
+			reader: strings.NewReader(""),
 		},
 		{
 			name:    "Error reader",
@@ -550,6 +549,10 @@ func TestNewFromReader(t *testing.T) {
 				return
 			}
 			assert.NoError(t, err)
+
+			if rdr == nil {
+				return
+			}
 			defer rdr.Close()
 
 			_, err = b.ReadFrom(rdr)