lightning: support compress for lightning, add compress unit and integration tests

br/pkg/lightning/mydump/reader.go

@@ -70,6 +70,13 @@ func decodeCharacterSet(data []byte, characterSet string) ([]byte, error) {
 
 // ExportStatement exports the SQL statement in the schema file.
 func ExportStatement(ctx context.Context, store storage.ExternalStorage, sqlFile FileInfo, characterSet string) ([]byte, error) {
+	if sqlFile.FileMeta.Compression != CompressionNone {
+		compressType, err := ToStorageCompressType(sqlFile.FileMeta.Compression)
+		if err != nil {
+			return nil, errors.Trace(err)
+		}
+		store = storage.WithCompression(store, compressType)
+	}
 	fd, err := store.Open(ctx, sqlFile.FileMeta.Path)
 	if err != nil {
 		return nil, errors.Trace(err)

br/pkg/lightning/mydump/reader_test.go

@@ -15,6 +15,7 @@
 package mydump_test
 
 import (
+	"compress/gzip"
 	"context"
 	"errors"
 	"os"
@@ -173,3 +174,28 @@ func TestExportStatementHandleNonEOFError(t *testing.T) {
 	_, err := ExportStatement(ctx, mockStorage, f, "auto")
 	require.Contains(t, err.Error(), "read error")
 }
+
+func TestExportStatementCompressed(t *testing.T) {
+	dir := t.TempDir()
+	file, err := os.Create(filepath.Join(dir, "tidb_lightning_test_reader"))
+	require.NoError(t, err)
+	defer os.Remove(file.Name())
+
+	store, err := storage.NewLocalStorage(dir)
+	require.NoError(t, err)
+
+	gzipFile := gzip.NewWriter(file)
+	_, err = gzipFile.Write([]byte("CREATE DATABASE whatever;"))
+	require.NoError(t, err)
+	err = gzipFile.Close()
+	require.NoError(t, err)
+	stat, err := file.Stat()
+	require.NoError(t, err)
+	err = file.Close()
+	require.NoError(t, err)
+
+	f := FileInfo{FileMeta: SourceFileMeta{Path: stat.Name(), FileSize: stat.Size(), Compression: CompressionGZ}}
+	data, err := ExportStatement(context.TODO(), store, f, "auto")
+	require.NoError(t, err)
+	require.Equal(t, []byte("CREATE DATABASE whatever;"), data)
+}

br/pkg/lightning/mydump/region.go

@@ -34,6 +34,9 @@ const (
 	tableRegionSizeWarningThreshold int64 = 1024 * 1024 * 1024
 	// the increment ratio of large CSV file size threshold by `region-split-size`
 	largeCSVLowerThresholdRation = 10
+	// TableFileSizeINF for compressed size, for lightning 10TB is a relatively big value and will strongly affect efficiency
+	// It's used to make sure compressed files can be read until EOF. Because we can't get the exact decompressed size of the compressed files.
+	TableFileSizeINF = 10 * 1024 * tableRegionSizeWarningThreshold
 )
 
 // TableRegion contains information for a table region during import.
@@ -292,19 +295,28 @@ func MakeSourceFileRegion(
 		return regions, subFileSizes, err
 	}
 
+	fileSize := fi.FileMeta.FileSize
+	rowIDMax := fileSize / divisor
+	// for compressed files, suggest the compress ratio is 1% to calculate the rowIDMax.
+	// set fileSize to INF to make sure compressed files can be read until EOF. Because we can't get the exact size of the compressed files.
+	// TODO: update progress bar calculation for compressed files.
+	if fi.FileMeta.Compression != CompressionNone {
+		rowIDMax = fileSize * 100 / divisor // FIXME: this is not accurate. Need more tests and fix solution.
+		fileSize = TableFileSizeINF
+	}
 	tableRegion := &TableRegion{
 		DB:       meta.DB,
 		Table:    meta.Name,
 		FileMeta: fi.FileMeta,
 		Chunk: Chunk{
 			Offset:       0,
-			EndOffset:    fi.FileMeta.FileSize,
+			EndOffset:    fileSize,
 			PrevRowIDMax: 0,
-			RowIDMax:     fi.FileMeta.FileSize / divisor,
+			RowIDMax:     rowIDMax,
 		},
 	}
 
-	if tableRegion.Size() > tableRegionSizeWarningThreshold {
+	if fi.FileMeta.Compression == CompressionNone && tableRegion.Size() > tableRegionSizeWarningThreshold {
 		log.FromContext(ctx).Warn(
 			"file is too big to be processed efficiently; we suggest splitting it at 256 MB each",
 			zap.String("file", fi.FileMeta.Path),

br/pkg/lightning/mydump/region_test.go

@@ -217,7 +217,7 @@ func TestMakeSourceFileRegion(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Len(t, regions, 1)
 	assert.Equal(t, int64(0), regions[0].Chunk.Offset)
-	assert.Equal(t, fileInfo.FileMeta.FileSize, regions[0].Chunk.EndOffset)
+	assert.Equal(t, TableFileSizeINF, regions[0].Chunk.EndOffset)
 	assert.Len(t, regions[0].Chunk.Columns, 0)
 }
 

br/pkg/lightning/mydump/router.go

@@ -134,7 +134,7 @@ func parseCompressionType(t string) (Compression, error) {
 		return CompressionGZ, nil
 	case "lz4":
 		return CompressionLZ4, nil
-	case "zstd":
+	case "zstd", "zst":
 		return CompressionZStd, nil
 	case "xz":
 		return CompressionXZ, nil
@@ -324,6 +324,9 @@ func (p regexRouterParser) Parse(r *config.FileRouteRule, logger log.Logger) (*R
 			if err != nil {
 				return err
 			}
+			if result.Type == SourceTypeParquet && compression != CompressionNone {
+				return errors.Errorf("can't support whole compressed parquet file, should compress parquet files by choosing correct parquet compress writer, path: %s", r.Path)
+			}
 			result.Compression = compression
 			return nil
 		})

br/pkg/lightning/mydump/router_test.go

@@ -292,3 +292,21 @@ func TestRouteWithPath(t *testing.T) {
 	require.NoError(t, err)
 	require.Nil(t, res)
 }
+
+func TestRouteWithCompressedParquet(t *testing.T) {
+	fileName := "myschema.my_table.000.parquet.gz"
+	rule := &config.FileRouteRule{
+		Pattern:     `(?i)^(?:[^/]*/)*([^/.]+)\.(.*?)(?:\.([0-9]+))?\.(sql|csv|parquet)(?:\.(\w+))?$`,
+		Schema:      "$1",
+		Table:       "$2",
+		Type:        "$4",
+		Key:         "$3",
+		Compression: "$5",
+		Unescape:    true,
+	}
+	r := *rule
+	router, err := NewFileRouter([]*config.FileRouteRule{&r}, log.L())
+	require.NoError(t, err)
+	_, err = router.Route(fileName)
+	require.Error(t, err)
+}

br/pkg/lightning/restore/get_pre_info.go

@@ -444,15 +444,7 @@ func (p *PreRestoreInfoGetterImpl) ReadFirstNRowsByTableName(ctx context.Context
 // ReadFirstNRowsByFileMeta reads the first N rows of an data file.
 // It implements the PreRestoreInfoGetter interface.
 func (p *PreRestoreInfoGetterImpl) ReadFirstNRowsByFileMeta(ctx context.Context, dataFileMeta mydump.SourceFileMeta, n int) ([]string, [][]types.Datum, error) {
-	var (
-		reader storage.ReadSeekCloser
-		err    error
-	)
-	if dataFileMeta.Type == mydump.SourceTypeParquet {
-		reader, err = mydump.OpenParquetReader(ctx, p.srcStorage, dataFileMeta.Path, dataFileMeta.FileSize)
-	} else {
-		reader, err = p.srcStorage.Open(ctx, dataFileMeta.Path)
-	}
+	reader, err := openReader(ctx, dataFileMeta, p.srcStorage)
 	if err != nil {
 		return nil, nil, errors.Trace(err)
 	}
@@ -590,13 +582,7 @@ func (p *PreRestoreInfoGetterImpl) sampleDataFromTable(
 		return resultIndexRatio, isRowOrdered, nil
 	}
 	sampleFile := tableMeta.DataFiles[0].FileMeta
-	var reader storage.ReadSeekCloser
-	var err error
-	if sampleFile.Type == mydump.SourceTypeParquet {
-		reader, err = mydump.OpenParquetReader(ctx, p.srcStorage, sampleFile.Path, sampleFile.FileSize)
-	} else {
-		reader, err = p.srcStorage.Open(ctx, sampleFile.Path)
-	}
+	reader, err := openReader(ctx, sampleFile, p.srcStorage)
 	if err != nil {
 		return 0.0, false, errors.Trace(err)
 	}