channeldb: prepare RevocationLog for optional fields

This commit is a pure refactor. It restructures the RevocationLog
serialize and deserialize methods so that optional TLV fields can be
easily added.

channeldb/migration30/revocation_log.go

@@ -16,8 +16,18 @@ import (
 	"github.com/lightningnetwork/lnd/tlv"
 )
 
-// OutputIndexEmpty is used when the output index doesn't exist.
+const (
-const OutputIndexEmpty = math.MaxUint16
+	// OutputIndexEmpty is used when the output index doesn't exist.
+	OutputIndexEmpty = math.MaxUint16
+
+	// A set of tlv type definitions used to serialize the body of
+	// revocation logs to the database.
+	//
+	// NOTE: A migration should be added whenever this list changes.
+	revLogOurOutputIndexType   tlv.Type = 0
+	revLogTheirOutputIndexType tlv.Type = 1
+	revLogCommitTxHashType     tlv.Type = 2
+)
 
 var (
 	// revocationLogBucketDeprecated is dedicated for storing the necessary
@@ -208,29 +218,6 @@ type RevocationLog struct {
 	HTLCEntries []*HTLCEntry
 }
 
-// toTlvStream converts an RevocationLog record into a tlv representation.
-func (rl *RevocationLog) toTlvStream() (*tlv.Stream, error) {
-	const (
-		// A set of tlv type definitions used to serialize the body of
-		// revocation logs to the database. We define it here instead
-		// of the head of the file to avoid naming conflicts.
-		//
-		// NOTE: A migration should be added whenever this list
-		// changes.
-		ourOutputIndexType   tlv.Type = 0
-		theirOutputIndexType tlv.Type = 1
-		commitTxHashType     tlv.Type = 2
-	)
-
-	return tlv.NewStream(
-		tlv.MakePrimitiveRecord(ourOutputIndexType, &rl.OurOutputIndex),
-		tlv.MakePrimitiveRecord(
-			theirOutputIndexType, &rl.TheirOutputIndex,
-		),
-		tlv.MakePrimitiveRecord(commitTxHashType, &rl.CommitTxHash),
-	)
-}
-
 // putRevocationLog uses the fields `CommitTx` and `Htlcs` from a
 // ChannelCommitment to construct a revocation log entry and saves them to
 // disk. It also saves our output index and their output index, which are
@@ -304,8 +291,21 @@ func fetchRevocationLog(log kvdb.RBucket,
 // serializeRevocationLog serializes a RevocationLog record based on tlv
 // format.
 func serializeRevocationLog(w io.Writer, rl *RevocationLog) error {
+	// Add the tlv records for all non-optional fields.
+	records := []tlv.Record{
+		tlv.MakePrimitiveRecord(
+			revLogOurOutputIndexType, &rl.OurOutputIndex,
+		),
+		tlv.MakePrimitiveRecord(
+			revLogTheirOutputIndexType, &rl.TheirOutputIndex,
+		),
+		tlv.MakePrimitiveRecord(
+			revLogCommitTxHashType, &rl.CommitTxHash,
+		),
+	}
+
 	// Create the tlv stream.
-	tlvStream, err := rl.toTlvStream()
+	tlvStream, err := tlv.NewStream(records...)
 	if err != nil {
 		return err
 	}
@@ -351,13 +351,20 @@ func deserializeRevocationLog(r io.Reader) (RevocationLog, error) {
 	var rl RevocationLog
 
 	// Create the tlv stream.
-	tlvStream, err := rl.toTlvStream()
+	tlvStream, err := tlv.NewStream(
-	if err != nil {
+		tlv.MakePrimitiveRecord(
-		return rl, err
+			revLogOurOutputIndexType, &rl.OurOutputIndex,
-	}
+		),
+		tlv.MakePrimitiveRecord(
+			revLogTheirOutputIndexType, &rl.TheirOutputIndex,
+		),
+		tlv.MakePrimitiveRecord(
+			revLogCommitTxHashType, &rl.CommitTxHash,
+		),
+	)
 
 	// Read the tlv stream.
-	if err := readTlvStream(r, tlvStream); err != nil {
+	if _, err := readTlvStream(r, tlvStream); err != nil {
 		return rl, err
 	}
 
@@ -382,7 +389,7 @@ func deserializeHTLCEntries(r io.Reader) ([]*HTLCEntry, error) {
 		}
 
 		// Read the HTLC entry.
-		if err := readTlvStream(r, tlvStream); err != nil {
+		if _, err := readTlvStream(r, tlvStream); err != nil {
 			// We've reached the end when hitting an EOF.
 			if err == io.ErrUnexpectedEOF {
 				break
@@ -427,7 +434,7 @@ func writeTlvStream(w io.Writer, s *tlv.Stream) error {
 
 // readTlvStream is a helper function that decodes the tlv stream from the
 // reader.
-func readTlvStream(r io.Reader, s *tlv.Stream) error {
+func readTlvStream(r io.Reader, s *tlv.Stream) (tlv.TypeMap, error) {
 	var bodyLen uint64
 
 	// Read the stream's length.
@@ -436,16 +443,17 @@ func readTlvStream(r io.Reader, s *tlv.Stream) error {
 	// We'll convert any EOFs to ErrUnexpectedEOF, since this results in an
 	// invalid record.
 	case err == io.EOF:
-		return io.ErrUnexpectedEOF
+		return nil, io.ErrUnexpectedEOF
 
 	// Other unexpected errors.
 	case err != nil:
-		return err
+		return nil, err
 	}
 
 	// TODO(yy): add overflow check.
 	lr := io.LimitReader(r, int64(bodyLen))
-	return s.Decode(lr)
+
+	return s.DecodeWithParsedTypes(lr)
 }
 
 // fetchLogBucket returns a read bucket by visiting both the new and the old

channeldb/revocation_log.go

@@ -12,8 +12,18 @@ import (
 	"github.com/lightningnetwork/lnd/tlv"
 )
 
-// OutputIndexEmpty is used when the output index doesn't exist.
+const (
-const OutputIndexEmpty = math.MaxUint16
+	// OutputIndexEmpty is used when the output index doesn't exist.
+	OutputIndexEmpty = math.MaxUint16
+
+	// A set of tlv type definitions used to serialize the body of
+	// revocation logs to the database.
+	//
+	// NOTE: A migration should be added whenever this list changes.
+	revLogOurOutputIndexType   tlv.Type = 0
+	revLogTheirOutputIndexType tlv.Type = 1
+	revLogCommitTxHashType     tlv.Type = 2
+)
 
 var (
 	// revocationLogBucketDeprecated is dedicated for storing the necessary
@@ -196,29 +206,6 @@ type RevocationLog struct {
 	HTLCEntries []*HTLCEntry
 }
 
-// toTlvStream converts an RevocationLog record into a tlv representation.
-func (rl *RevocationLog) toTlvStream() (*tlv.Stream, error) {
-	const (
-		// A set of tlv type definitions used to serialize the body of
-		// revocation logs to the database. We define it here instead
-		// of the head of the file to avoid naming conflicts.
-		//
-		// NOTE: A migration should be added whenever this list
-		// changes.
-		ourOutputIndexType   tlv.Type = 0
-		theirOutputIndexType tlv.Type = 1
-		commitTxHashType     tlv.Type = 2
-	)
-
-	return tlv.NewStream(
-		tlv.MakePrimitiveRecord(ourOutputIndexType, &rl.OurOutputIndex),
-		tlv.MakePrimitiveRecord(
-			theirOutputIndexType, &rl.TheirOutputIndex,
-		),
-		tlv.MakePrimitiveRecord(commitTxHashType, &rl.CommitTxHash),
-	)
-}
-
 // putRevocationLog uses the fields `CommitTx` and `Htlcs` from a
 // ChannelCommitment to construct a revocation log entry and saves them to
 // disk. It also saves our output index and their output index, which are
@@ -292,8 +279,21 @@ func fetchRevocationLog(log kvdb.RBucket,
 // serializeRevocationLog serializes a RevocationLog record based on tlv
 // format.
 func serializeRevocationLog(w io.Writer, rl *RevocationLog) error {
+	// Add the tlv records for all non-optional fields.
+	records := []tlv.Record{
+		tlv.MakePrimitiveRecord(
+			revLogOurOutputIndexType, &rl.OurOutputIndex,
+		),
+		tlv.MakePrimitiveRecord(
+			revLogTheirOutputIndexType, &rl.TheirOutputIndex,
+		),
+		tlv.MakePrimitiveRecord(
+			revLogCommitTxHashType, &rl.CommitTxHash,
+		),
+	}
+
 	// Create the tlv stream.
-	tlvStream, err := rl.toTlvStream()
+	tlvStream, err := tlv.NewStream(records...)
 	if err != nil {
 		return err
 	}
@@ -339,13 +339,20 @@ func deserializeRevocationLog(r io.Reader) (RevocationLog, error) {
 	var rl RevocationLog
 
 	// Create the tlv stream.
-	tlvStream, err := rl.toTlvStream()
+	tlvStream, err := tlv.NewStream(
-	if err != nil {
+		tlv.MakePrimitiveRecord(
-		return rl, err
+			revLogOurOutputIndexType, &rl.OurOutputIndex,
-	}
+		),
+		tlv.MakePrimitiveRecord(
+			revLogTheirOutputIndexType, &rl.TheirOutputIndex,
+		),
+		tlv.MakePrimitiveRecord(
+			revLogCommitTxHashType, &rl.CommitTxHash,
+		),
+	)
 
 	// Read the tlv stream.
-	if err := readTlvStream(r, tlvStream); err != nil {
+	if _, err := readTlvStream(r, tlvStream); err != nil {
 		return rl, err
 	}
 
@@ -370,7 +377,7 @@ func deserializeHTLCEntries(r io.Reader) ([]*HTLCEntry, error) {
 		}
 
 		// Read the HTLC entry.
-		if err := readTlvStream(r, tlvStream); err != nil {
+		if _, err := readTlvStream(r, tlvStream); err != nil {
 			// We've reached the end when hitting an EOF.
 			if err == io.ErrUnexpectedEOF {
 				break
@@ -415,7 +422,7 @@ func writeTlvStream(w io.Writer, s *tlv.Stream) error {
 
 // readTlvStream is a helper function that decodes the tlv stream from the
 // reader.
-func readTlvStream(r io.Reader, s *tlv.Stream) error {
+func readTlvStream(r io.Reader, s *tlv.Stream) (tlv.TypeMap, error) {
 	var bodyLen uint64
 
 	// Read the stream's length.
@@ -424,16 +431,17 @@ func readTlvStream(r io.Reader, s *tlv.Stream) error {
 	// We'll convert any EOFs to ErrUnexpectedEOF, since this results in an
 	// invalid record.
 	case err == io.EOF:
-		return io.ErrUnexpectedEOF
+		return nil, io.ErrUnexpectedEOF
 
 	// Other unexpected errors.
 	case err != nil:
-		return err
+		return nil, err
 	}
 
 	// TODO(yy): add overflow check.
 	lr := io.LimitReader(r, int64(bodyLen))
-	return s.Decode(lr)
+
+	return s.DecodeWithParsedTypes(lr)
 }
 
 // fetchOldRevocationLog finds the revocation log from the deprecated

channeldb/revocation_log_test.go

@@ -127,7 +127,7 @@ func TestReadTLVStream(t *testing.T) {
 
 	// Read the tlv stream.
 	buf := bytes.NewBuffer(testValueBytes)
-	err = readTlvStream(buf, ts)
+	_, err = readTlvStream(buf, ts)
 	require.NoError(t, err)
 
 	// Check the bytes are read as expected.
@@ -150,7 +150,7 @@ func TestReadTLVStreamErr(t *testing.T) {
 
 	// Read the tlv stream.
 	buf := bytes.NewBuffer(b)
-	err = readTlvStream(buf, ts)
+	_, err = readTlvStream(buf, ts)
 	require.ErrorIs(t, err, io.ErrUnexpectedEOF)
 
 	// Check the bytes are not read.