cmd: export preimages in RLP, support GZIP, uniform with block export

cmd/geth/chaincmd.go

@@ -40,11 +40,6 @@ import (
 	"gopkg.in/urfave/cli.v1"
 )
 
-var (
-	// secureKeyPrefix is the database key prefix used to store trie node preimages.
-	secureKeyPrefix = []byte("secure-key-")
-)
-
 var (
 	initCommand = cli.Command{
 		Action:    utils.MigrateFlags(initGenesis),
@@ -100,6 +95,34 @@ Requires a first argument of the file to write to.
 Optional second and third arguments control the first and
 last block to write. In this mode, the file will be appended
 if already existing.`,
+	}
+	importPreimagesCommand = cli.Command{
+		Action:    utils.MigrateFlags(importPreimages),
+		Name:      "import-preimages",
+		Usage:     "Import the preimage database from an RLP stream",
+		ArgsUsage: "<datafile>",
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+			utils.CacheFlag,
+			utils.LightModeFlag,
+		},
+		Category: "BLOCKCHAIN COMMANDS",
+		Description: `
+	The import-preimages command imports hash preimages from an RLP encoded stream.`,
+	}
+	exportPreimagesCommand = cli.Command{
+		Action:    utils.MigrateFlags(exportPreimages),
+		Name:      "export-preimages",
+		Usage:     "Export the preimage database into an RLP stream",
+		ArgsUsage: "<dumpfile>",
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+			utils.CacheFlag,
+			utils.LightModeFlag,
+		},
+		Category: "BLOCKCHAIN COMMANDS",
+		Description: `
+The export-preimages command export hash preimages to an RLP encoded stream`,
 	}
 	copydbCommand = cli.Command{
 		Action:    utils.MigrateFlags(copyDb),
@@ -146,34 +169,6 @@ Remove blockchain and state databases`,
 The arguments are interpreted as block numbers or hashes.
 Use "ethereum dump 0" to dump the genesis block.`,
 	}
-	preimageDumpCommand = cli.Command{
-		Action:    utils.MigrateFlags(dumpPreimage),
-		Name:      "preimagedump",
-		Usage:     "Dump the preimage database in json format",
-		ArgsUsage: "<dumpfile>",
-		Flags: []cli.Flag{
-			utils.DataDirFlag,
-			utils.CacheFlag,
-			utils.LightModeFlag,
-		},
-		Category: "BLOCKCHAIN COMMANDS",
-		Description: `
-Dump the preimage database in json format`,
-	}
-	preimageImportCommand = cli.Command{
-		Action:    utils.MigrateFlags(importPreimage),
-		Name:      "preimageimport",
-		Usage:     "Import the preimage data from the specified file",
-		ArgsUsage: "<datafile>",
-		Flags: []cli.Flag{
-			utils.DataDirFlag,
-			utils.CacheFlag,
-			utils.LightModeFlag,
-		},
-		Category: "BLOCKCHAIN COMMANDS",
-		Description: `
-Import the preimage data from the specified file`,
-	}
 )
 
 // initGenesis will initialise the given JSON format genesis file and writes it as
@@ -332,7 +327,39 @@ func exportChain(ctx *cli.Context) error {
 	if err != nil {
 		utils.Fatalf("Export error: %v\n", err)
 	}
-	fmt.Printf("Export done in %v", time.Since(start))
+	fmt.Printf("Export done in %v\n", time.Since(start))
+	return nil
+}
+
+// importPreimages imports preimage data from the specified file.
+func importPreimages(ctx *cli.Context) error {
+	if len(ctx.Args()) < 1 {
+		utils.Fatalf("This command requires an argument.")
+	}
+	stack := makeFullNode(ctx)
+	diskdb := utils.MakeChainDatabase(ctx, stack).(*ethdb.LDBDatabase)
+
+	start := time.Now()
+	if err := utils.ImportPreimages(diskdb, ctx.Args().First()); err != nil {
+		utils.Fatalf("Export error: %v\n", err)
+	}
+	fmt.Printf("Export done in %v\n", time.Since(start))
+	return nil
+}
+
+// exportPreimages dumps the preimage data to specified json file in streaming way.
+func exportPreimages(ctx *cli.Context) error {
+	if len(ctx.Args()) < 1 {
+		utils.Fatalf("This command requires an argument.")
+	}
+	stack := makeFullNode(ctx)
+	diskdb := utils.MakeChainDatabase(ctx, stack).(*ethdb.LDBDatabase)
+
+	start := time.Now()
+	if err := utils.ExportPreimages(diskdb, ctx.Args().First()); err != nil {
+		utils.Fatalf("Export error: %v\n", err)
+	}
+	fmt.Printf("Export done in %v\n", time.Since(start))
 	return nil
 }
 
@@ -439,86 +466,6 @@ func dump(ctx *cli.Context) error {
 	return nil
 }
 
-// PreimageEntry represents a map between preimage and hash.
-type PreimageEntry struct {
-	Hash     string `json:"hash"`
-	Preimage string `json:"preimage"`
-}
-
-// dumpPreimage dumps the preimage data to specified json file in streaming way.
-func dumpPreimage(ctx *cli.Context) error {
-	// Make sure the export json file has been specified.
-	if len(ctx.Args()) < 1 {
-		utils.Fatalf("This command requires an argument.")
-	}
-
-	// Encode preimage data to json file in streaming way.
-	file, err := os.Create(ctx.Args().First())
-	if err != nil {
-		return err
-	}
-	encoder := json.NewEncoder(file)
-
-	stack := makeFullNode(ctx)
-	db := utils.MakeChainDatabase(ctx, stack)
-
-	// Dump all preimage entries.
-	it := db.(*ethdb.LDBDatabase).NewIteratorByPrefix(secureKeyPrefix)
-	for it.Next() {
-		hash := it.Key()[len(secureKeyPrefix):]
-		if err := encoder.Encode(PreimageEntry{common.Bytes2Hex(hash), common.Bytes2Hex(it.Value())}); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-// importPreimages imports preimage data from the specified file.
-func importPreimage(ctx *cli.Context) error {
-	// Make sure the export json file has been specified.
-	if len(ctx.Args()) < 1 {
-		utils.Fatalf("This command requires an argument.")
-	}
-
-	// Decode the preimage data in streaming way.
-	file, err := os.Open(ctx.Args().First())
-	if err != nil {
-		return err
-	}
-	decoder := json.NewDecoder(file)
-
-	stack := makeFullNode(ctx)
-	db := utils.MakeChainDatabase(ctx, stack)
-
-	var (
-		entry     PreimageEntry
-		preimages = make(map[common.Hash][]byte)
-	)
-
-	for decoder.More() {
-		if err := decoder.Decode(&entry); err != nil {
-			return err
-		}
-		preimages[common.HexToHash(entry.Hash)] = common.Hex2Bytes(entry.Preimage)
-		// Flush to database in batch
-		if len(preimages) > 1024 {
-			err := core.WritePreimages(db, 0, preimages)
-			if err != nil {
-				return err
-			}
-			preimages = make(map[common.Hash][]byte)
-		}
-	}
-	// Flush the last batch preimage data
-	if len(preimages) > 0 {
-		err := core.WritePreimages(db, 0, preimages)
-		if err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
 // hashish returns true for strings that look like hashes.
 func hashish(x string) bool {
 	_, err := strconv.Atoi(x)

cmd/geth/main.go

@@ -155,11 +155,11 @@ func init() {
 		initCommand,
 		importCommand,
 		exportCommand,
+		importPreimagesCommand,
+		exportPreimagesCommand,
 		copydbCommand,
 		removedbCommand,
 		dumpCommand,
-		preimageDumpCommand,
-		preimageImportCommand,
 		// See monitorcmd.go:
 		monitorCommand,
 		// See accountcmd.go:

cmd/utils/cmd.go

@@ -27,8 +27,11 @@ import (
 	"strings"
 	"syscall"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/internal/debug"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/node"
@@ -105,6 +108,8 @@ func ImportChain(chain *core.BlockChain, fn string) error {
 	}
 
 	log.Info("Importing blockchain", "file", fn)
+
+	// Open the file handle and potentially unwrap the gzip stream
 	fh, err := os.Open(fn)
 	if err != nil {
 		return err
@@ -180,8 +185,12 @@ func missingBlocks(chain *core.BlockChain, blocks []*types.Block) []*types.Block
 	return nil
 }
 
+// ExportChain exports a blockchain into the specified file, truncating any data
+// already present in the file.
 func ExportChain(blockchain *core.BlockChain, fn string) error {
 	log.Info("Exporting blockchain", "file", fn)
+
+	// Open the file handle and potentially wrap with a gzip stream
 	fh, err := os.OpenFile(fn, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, os.ModePerm)
 	if err != nil {
 		return err
@@ -193,7 +202,7 @@ func ExportChain(blockchain *core.BlockChain, fn string) error {
 		writer = gzip.NewWriter(writer)
 		defer writer.(*gzip.Writer).Close()
 	}
-
+	// Iterate over the blocks and export them
 	if err := blockchain.Export(writer); err != nil {
 		return err
 	}
@@ -202,9 +211,12 @@ func ExportChain(blockchain *core.BlockChain, fn string) error {
 	return nil
 }
 
+// ExportAppendChain exports a blockchain into the specified file, appending to
+// the file if data already exists in it.
 func ExportAppendChain(blockchain *core.BlockChain, fn string, first uint64, last uint64) error {
 	log.Info("Exporting blockchain", "file", fn)
-	// TODO verify mode perms
+
+	// Open the file handle and potentially wrap with a gzip stream
 	fh, err := os.OpenFile(fn, os.O_CREATE|os.O_APPEND|os.O_WRONLY, os.ModePerm)
 	if err != nil {
 		return err
@@ -216,10 +228,86 @@ func ExportAppendChain(blockchain *core.BlockChain, fn string, first uint64, las
 		writer = gzip.NewWriter(writer)
 		defer writer.(*gzip.Writer).Close()
 	}
-
+	// Iterate over the blocks and export them
 	if err := blockchain.ExportN(writer, first, last); err != nil {
 		return err
 	}
 	log.Info("Exported blockchain to", "file", fn)
 	return nil
 }
+
+// ImportPreimages imports a batch of exported hash preimages into the database.
+func ImportPreimages(db *ethdb.LDBDatabase, fn string) error {
+	log.Info("Importing preimages", "file", fn)
+
+	// Open the file handle and potentially unwrap the gzip stream
+	fh, err := os.Open(fn)
+	if err != nil {
+		return err
+	}
+	defer fh.Close()
+
+	var reader io.Reader = fh
+	if strings.HasSuffix(fn, ".gz") {
+		if reader, err = gzip.NewReader(reader); err != nil {
+			return err
+		}
+	}
+	stream := rlp.NewStream(reader, 0)
+
+	// Import the preimages in batches to prevent disk trashing
+	preimages := make(map[common.Hash][]byte)
+
+	for {
+		// Read the next entry and ensure it's not junk
+		var blob []byte
+
+		if err := stream.Decode(&blob); err != nil {
+			if err == io.EOF {
+				break
+			}
+			return err
+		}
+		// Accumulate the preimages and flush when enough ws gathered
+		preimages[crypto.Keccak256Hash(blob)] = common.CopyBytes(blob)
+		if len(preimages) > 1024 {
+			if err := core.WritePreimages(db, 0, preimages); err != nil {
+				return err
+			}
+			preimages = make(map[common.Hash][]byte)
+		}
+	}
+	// Flush the last batch preimage data
+	if len(preimages) > 0 {
+		return core.WritePreimages(db, 0, preimages)
+	}
+	return nil
+}
+
+// ExportPreimages exports all known hash preimages into the specified file,
+// truncating any data already present in the file.
+func ExportPreimages(db *ethdb.LDBDatabase, fn string) error {
+	log.Info("Exporting preimages", "file", fn)
+
+	// Open the file handle and potentially wrap with a gzip stream
+	fh, err := os.OpenFile(fn, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, os.ModePerm)
+	if err != nil {
+		return err
+	}
+	defer fh.Close()
+
+	var writer io.Writer = fh
+	if strings.HasSuffix(fn, ".gz") {
+		writer = gzip.NewWriter(writer)
+		defer writer.(*gzip.Writer).Close()
+	}
+	// Iterate over the preimages and export them
+	it := db.NewIteratorWithPrefix([]byte("secure-key-"))
+	for it.Next() {
+		if err := rlp.Encode(writer, it.Value()); err != nil {
+			return err
+		}
+	}
+	log.Info("Exported preimages", "file", fn)
+	return nil
+}

ethdb/database.go

@@ -122,8 +122,8 @@ func (db *LDBDatabase) NewIterator() iterator.Iterator {
 	return db.db.NewIterator(nil, nil)
 }
 
-// NewIteratorByPrefix returns a iterator to iterate over subset of database content with a particular prefix.
+// NewIteratorWithPrefix returns a iterator to iterate over subset of database content with a particular prefix.
-func (db *LDBDatabase) NewIteratorByPrefix(prefix []byte) iterator.Iterator {
+func (db *LDBDatabase) NewIteratorWithPrefix(prefix []byte) iterator.Iterator {
 	return db.db.NewIterator(util.BytesPrefix(prefix), nil)
 }