feat: Add brotli compression support

cmd/stbak/cmd/archive.go

@@ -10,6 +10,7 @@ import (
 	"path/filepath"
 	"strconv"
 
+	"github.com/andybalholm/brotli"
 	"github.com/klauspost/compress/zstd"
 	"github.com/klauspost/pgzip"
 	"github.com/pierrec/lz4/v4"
@@ -291,6 +292,40 @@ func archive(
 				hdr.Size = int64(fileSizeCounter.BytesRead)
 
 				hdr.Name += compressionFormatZStandardSuffix
+			case compressionFormatBrotliKey:
+				// Get the compressed size for the header
+				file, err := os.Open(path)
+				if err != nil {
+					return err
+				}
+
+				fileSizeCounter := counters.CounterWriter{
+					Writer: io.Discard,
+				}
+
+				br := brotli.NewWriter(&fileSizeCounter)
+
+				if _, err := io.Copy(br, file); err != nil {
+					return err
+				}
+
+				if err := br.Flush(); err != nil {
+					return err
+				}
+				if err := br.Close(); err != nil {
+					return err
+				}
+				if err := file.Close(); err != nil {
+					return err
+				}
+
+				if hdr.PAXRecords == nil {
+					hdr.PAXRecords = map[string]string{}
+				}
+				hdr.PAXRecords[pax.STFSRecordUncompressedSize] = strconv.Itoa(int(hdr.Size))
+				hdr.Size = int64(fileSizeCounter.BytesRead)
+
+				hdr.Name += compressionFormatBrotliSuffix
 			case compressionFormatNoneKey:
 			default:
 				return errUnsupportedCompressionFormat
@@ -426,6 +461,39 @@ func archive(
 			if err := file.Close(); err != nil {
 				return err
 			}
+		case compressionFormatBrotliKey:
+			// Compress and write the file
+			file, err := os.Open(path)
+			if err != nil {
+				return err
+			}
+
+			br := brotli.NewWriter(tw)
+
+			if _, err := io.Copy(br, file); err != nil {
+				return err
+			}
+
+			if isRegular {
+				if _, err := io.Copy(br, file); err != nil {
+					return err
+				}
+			} else {
+				buf := make([]byte, controllers.BlockSize*recordSize)
+				if _, err := io.CopyBuffer(br, file, buf); err != nil {
+					return err
+				}
+			}
+
+			if err := br.Flush(); err != nil {
+				return err
+			}
+			if err := br.Close(); err != nil {
+				return err
+			}
+			if err := file.Close(); err != nil {
+				return err
+			}
 		case compressionFormatNoneKey:
 			// Write the file
 			file, err := os.Open(path)

cmd/stbak/cmd/recovery_fetch.go

@@ -8,6 +8,7 @@ import (
 	"os"
 	"path/filepath"
 
+	"github.com/andybalholm/brotli"
 	"github.com/klauspost/compress/zstd"
 	"github.com/klauspost/pgzip"
 	"github.com/pierrec/lz4/v4"
@@ -170,6 +171,12 @@ func restoreFromRecordAndBlock(
 			if _, err := io.Copy(dstFile, zz); err != nil {
 				return err
 			}
+		case compressionFormatBrotliKey:
+			br := brotli.NewReader(tr)
+
+			if _, err := io.Copy(dstFile, br); err != nil {
+				return err
+			}
 		case compressionFormatNoneKey:
 			if _, err := io.Copy(dstFile, tr); err != nil {
 				return err

cmd/stbak/cmd/recovery_index.go

@@ -277,6 +277,8 @@ func indexHeader(
 			hdr.Name = strings.TrimSuffix(hdr.Name, compressionFormatLZ4Suffix)
 		case compressionFormatZStandardKey:
 			hdr.Name = strings.TrimSuffix(hdr.Name, compressionFormatZStandardSuffix)
+		case compressionFormatBrotliKey:
+			hdr.Name = strings.TrimSuffix(hdr.Name, compressionFormatBrotliSuffix)
 		case compressionFormatNoneKey:
 		default:
 			return errUnsupportedCompressionFormat

cmd/stbak/cmd/root.go

@@ -29,10 +29,13 @@ const (
 
 	compressionFormatZStandardKey    = "zstandard"
 	compressionFormatZStandardSuffix = ".zst"
+
+	compressionFormatBrotliKey    = "brotli"
+	compressionFormatBrotliSuffix = ".br"
 )
 
 var (
-	knownCompressionFormats = []string{compressionFormatNoneKey, compressionFormatGZipKey, compressionFormatParallelGZipKey, compressionFormatLZ4Key, compressionFormatZStandardKey}
+	knownCompressionFormats = []string{compressionFormatNoneKey, compressionFormatGZipKey, compressionFormatParallelGZipKey, compressionFormatLZ4Key, compressionFormatZStandardKey, compressionFormatBrotliKey}
 
 	errUnknownCompressionFormat     = errors.New("unknown compression format")
 	errUnsupportedCompressionFormat = errors.New("unsupported compression format")