channeldb/graphdb: move outpoint ser/deser funcs to graphdb

We have the same helpers for writing and reading a wire.Outpoint type
defined separately in a couple places. We will want to use these from
the graph db package soon though so instead of defining them again
there, this commit unifies things and creates a single exported set of
helpers. The next commit will make use of these.

channeldb/channel.go

@@ -21,6 +21,7 @@ import (
 	"github.com/btcsuite/btcwallet/walletdb"
 	"github.com/lightningnetwork/lnd/channeldb/models"
 	"github.com/lightningnetwork/lnd/fn"
+	graphdb "github.com/lightningnetwork/lnd/graph/db"
 	"github.com/lightningnetwork/lnd/htlcswitch/hop"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
@@ -1330,7 +1331,7 @@ func fetchChanBucket(tx kvdb.RTx, nodeKey *btcec.PublicKey,
 	// With the bucket for the node and chain fetched, we can now go down
 	// another level, for this channel itself.
 	var chanPointBuf bytes.Buffer
-	if err := writeOutpoint(&chanPointBuf, outPoint); err != nil {
+	if err := graphdb.WriteOutpoint(&chanPointBuf, outPoint); err != nil {
 		return nil, err
 	}
 	chanBucket := chainBucket.NestedReadBucket(chanPointBuf.Bytes())
@@ -1377,7 +1378,7 @@ func fetchChanBucketRw(tx kvdb.RwTx, nodeKey *btcec.PublicKey,
 	// With the bucket for the node and chain fetched, we can now go down
 	// another level, for this channel itself.
 	var chanPointBuf bytes.Buffer
-	if err := writeOutpoint(&chanPointBuf, outPoint); err != nil {
+	if err := graphdb.WriteOutpoint(&chanPointBuf, outPoint); err != nil {
 		return nil, err
 	}
 	chanBucket := chainBucket.NestedReadWriteBucket(chanPointBuf.Bytes())
@@ -1422,7 +1423,8 @@ func (c *OpenChannel) fullSync(tx kvdb.RwTx) error {
 	}
 
 	var chanPointBuf bytes.Buffer
-	if err := writeOutpoint(&chanPointBuf, &c.FundingOutpoint); err != nil {
+	err := graphdb.WriteOutpoint(&chanPointBuf, &c.FundingOutpoint)
+	if err != nil {
 		return err
 	}
 
@@ -3822,7 +3824,7 @@ func (c *OpenChannel) CloseChannel(summary *ChannelCloseSummary,
 		}
 
 		var chanPointBuf bytes.Buffer
-		err := writeOutpoint(&chanPointBuf, &c.FundingOutpoint)
+		err := graphdb.WriteOutpoint(&chanPointBuf, &c.FundingOutpoint)
 		if err != nil {
 			return err
 		}

channeldb/codec.go

@@ -18,32 +18,6 @@ import (
 	"github.com/lightningnetwork/lnd/tlv"
 )
 
-// writeOutpoint writes an outpoint to the passed writer using the minimal
-// amount of bytes possible.
-func writeOutpoint(w io.Writer, o *wire.OutPoint) error {
-	if _, err := w.Write(o.Hash[:]); err != nil {
-		return err
-	}
-	if err := binary.Write(w, byteOrder, o.Index); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-// readOutpoint reads an outpoint from the passed reader that was previously
-// written using the writeOutpoint struct.
-func readOutpoint(r io.Reader, o *wire.OutPoint) error {
-	if _, err := io.ReadFull(r, o.Hash[:]); err != nil {
-		return err
-	}
-	if err := binary.Read(r, byteOrder, &o.Index); err != nil {
-		return err
-	}
-
-	return nil
-}
-
 // UnknownElementType is an error returned when the codec is unable to encode or
 // decode a particular type.
 type UnknownElementType struct {
@@ -99,7 +73,7 @@ func WriteElement(w io.Writer, element interface{}) error {
 		}
 
 	case wire.OutPoint:
-		return writeOutpoint(w, &e)
+		return graphdb.WriteOutpoint(w, &e)
 
 	case lnwire.ShortChannelID:
 		if err := binary.Write(w, byteOrder, e.ToUint64()); err != nil {
@@ -289,7 +263,7 @@ func ReadElement(r io.Reader, element interface{}) error {
 		}
 
 	case *wire.OutPoint:
-		return readOutpoint(r, e)
+		return graphdb.ReadOutpoint(r, e)
 
 	case *lnwire.ShortChannelID:
 		var a uint64

channeldb/db.go

@@ -30,6 +30,7 @@ import (
 	"github.com/lightningnetwork/lnd/channeldb/migration33"
 	"github.com/lightningnetwork/lnd/channeldb/migration_01_to_11"
 	"github.com/lightningnetwork/lnd/clock"
+	graphdb "github.com/lightningnetwork/lnd/graph/db"
 	"github.com/lightningnetwork/lnd/invoices"
 	"github.com/lightningnetwork/lnd/kvdb"
 	"github.com/lightningnetwork/lnd/lnwire"
@@ -646,7 +647,9 @@ func (c *ChannelStateDB) fetchNodeChannels(chainBucket kvdb.RBucket) (
 		chanBucket := chainBucket.NestedReadBucket(chanPoint)
 
 		var outPoint wire.OutPoint
-		err := readOutpoint(bytes.NewReader(chanPoint), &outPoint)
+		err := graphdb.ReadOutpoint(
+			bytes.NewReader(chanPoint), &outPoint,
+		)
 		if err != nil {
 			return err
 		}
@@ -675,7 +678,8 @@ func (c *ChannelStateDB) FetchChannel(tx kvdb.RTx, chanPoint wire.OutPoint) (
 	*OpenChannel, error) {
 
 	var targetChanPoint bytes.Buffer
-	if err := writeOutpoint(&targetChanPoint, &chanPoint); err != nil {
+	err := graphdb.WriteOutpoint(&targetChanPoint, &chanPoint)
+	if err != nil {
 		return nil, err
 	}
 
@@ -709,7 +713,9 @@ func (c *ChannelStateDB) FetchChannelByID(tx kvdb.RTx, id lnwire.ChannelID) (
 		)
 		err := chainBkt.ForEach(func(k, _ []byte) error {
 			var outPoint wire.OutPoint
-			err := readOutpoint(bytes.NewReader(k), &outPoint)
+			err := graphdb.ReadOutpoint(
+				bytes.NewReader(k), &outPoint,
+			)
 			if err != nil {
 				return err
 			}
@@ -1089,7 +1095,7 @@ func (c *ChannelStateDB) FetchClosedChannel(chanID *wire.OutPoint) (
 
 		var b bytes.Buffer
 		var err error
-		if err = writeOutpoint(&b, chanID); err != nil {
+		if err = graphdb.WriteOutpoint(&b, chanID); err != nil {
 			return err
 		}
 
@@ -1131,7 +1137,9 @@ func (c *ChannelStateDB) FetchClosedChannelForID(cid lnwire.ChannelID) (
 		// We scan over all possible candidates for this channel ID.
 		for ; op != nil && bytes.Compare(cid[:30], op[:30]) <= 0; op, c = cursor.Next() {
 			var outPoint wire.OutPoint
-			err := readOutpoint(bytes.NewReader(op), &outPoint)
+			err := graphdb.ReadOutpoint(
+				bytes.NewReader(op), &outPoint,
+			)
 			if err != nil {
 				return err
 			}
@@ -1173,7 +1181,7 @@ func (c *ChannelStateDB) MarkChanFullyClosed(chanPoint *wire.OutPoint) error {
 	)
 	err := kvdb.Update(c.backend, func(tx kvdb.RwTx) error {
 		var b bytes.Buffer
-		if err := writeOutpoint(&b, chanPoint); err != nil {
+		if err := graphdb.WriteOutpoint(&b, chanPoint); err != nil {
 			return err
 		}
 
@@ -1693,7 +1701,7 @@ func fetchHistoricalChanBucket(tx kvdb.RTx,
 	// With the bucket for the node and chain fetched, we can now go down
 	// another level, for the channel itself.
 	var chanPointBuf bytes.Buffer
-	if err := writeOutpoint(&chanPointBuf, outPoint); err != nil {
+	if err := graphdb.WriteOutpoint(&chanPointBuf, outPoint); err != nil {
 		return nil, err
 	}
 	chanBucket := historicalChanBucket.NestedReadBucket(

channeldb/graph.go

@@ -1129,7 +1129,7 @@ func (c *ChannelGraph) addChannelEdge(tx kvdb.RwTx,
 	// Finally we add it to the channel index which maps channel points
 	// (outpoints) to the shorter channel ID's.
 	var b bytes.Buffer
-	if err := writeOutpoint(&b, &edge.ChannelPoint); err != nil {
+	if err := graphdb.WriteOutpoint(&b, &edge.ChannelPoint); err != nil {
 		return err
 	}
 	return chanIndex.Put(b.Bytes(), chanKey[:])
@@ -1336,7 +1336,7 @@ func (c *ChannelGraph) PruneGraph(spentOutputs []*wire.OutPoint,
 			// if NOT if filter
 
 			var opBytes bytes.Buffer
-			if err := writeOutpoint(&opBytes, chanPoint); err != nil {
+			if err := graphdb.WriteOutpoint(&opBytes, chanPoint); err != nil {
 				return err
 			}
 
@@ -1808,7 +1808,7 @@ func (c *ChannelGraph) ChannelID(chanPoint *wire.OutPoint) (uint64, error) {
 // getChanID returns the assigned channel ID for a given channel point.
 func getChanID(tx kvdb.RTx, chanPoint *wire.OutPoint) (uint64, error) {
 	var b bytes.Buffer
-	if err := writeOutpoint(&b, chanPoint); err != nil {
+	if err := graphdb.WriteOutpoint(&b, chanPoint); err != nil {
 		return 0, err
 	}
 
@@ -2636,7 +2636,7 @@ func (c *ChannelGraph) delChannelEdgeUnsafe(edges, edgeIndex, chanIndex,
 		return err
 	}
 	var b bytes.Buffer
-	if err := writeOutpoint(&b, &edgeInfo.ChannelPoint); err != nil {
+	if err := graphdb.WriteOutpoint(&b, &edgeInfo.ChannelPoint); err != nil {
 		return err
 	}
 	if err := chanIndex.Delete(b.Bytes()); err != nil {
@@ -3414,7 +3414,7 @@ func (c *ChannelGraph) FetchChannelEdgesByOutpoint(op *wire.OutPoint) (
 			return ErrGraphNoEdgesFound
 		}
 		var b bytes.Buffer
-		if err := writeOutpoint(&b, op); err != nil {
+		if err := graphdb.WriteOutpoint(&b, op); err != nil {
 			return err
 		}
 		chanID := chanIndex.Get(b.Bytes())
@@ -3660,7 +3660,7 @@ func (c *ChannelGraph) ChannelView() ([]EdgePoint, error) {
 			chanPointReader := bytes.NewReader(chanPointBytes)
 
 			var chanPoint wire.OutPoint
-			err := readOutpoint(chanPointReader, &chanPoint)
+			err := graphdb.ReadOutpoint(chanPointReader, &chanPoint)
 			if err != nil {
 				return err
 			}
@@ -4282,7 +4282,7 @@ func putChanEdgeInfo(edgeIndex kvdb.RwBucket,
 		return err
 	}
 
-	if err := writeOutpoint(&b, &edgeInfo.ChannelPoint); err != nil {
+	if err := graphdb.WriteOutpoint(&b, &edgeInfo.ChannelPoint); err != nil {
 		return err
 	}
 	if err := binary.Write(&b, byteOrder, uint64(edgeInfo.Capacity)); err != nil {
@@ -4366,7 +4366,7 @@ func deserializeChanEdgeInfo(r io.Reader) (models.ChannelEdgeInfo, error) {
 	}
 
 	edgeInfo.ChannelPoint = wire.OutPoint{}
-	if err := readOutpoint(r, &edgeInfo.ChannelPoint); err != nil {
+	if err := graphdb.ReadOutpoint(r, &edgeInfo.ChannelPoint); err != nil {
 		return models.ChannelEdgeInfo{}, err
 	}
 	if err := binary.Read(r, byteOrder, &edgeInfo.Capacity); err != nil {

channeldb/reports.go

@@ -8,6 +8,7 @@ import (
 	"github.com/btcsuite/btcd/btcutil"
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/wire"
+	graphdb "github.com/lightningnetwork/lnd/graph/db"
 	"github.com/lightningnetwork/lnd/kvdb"
 	"github.com/lightningnetwork/lnd/tlv"
 )
@@ -164,7 +165,7 @@ func putReport(tx kvdb.RwTx, chainHash chainhash.Hash,
 
 	// Finally write our outpoint to be used as the key for this record.
 	var keyBuf bytes.Buffer
-	if err := writeOutpoint(&keyBuf, &report.OutPoint); err != nil {
+	if err := graphdb.WriteOutpoint(&keyBuf, &report.OutPoint); err != nil {
 		return err
 	}
 
@@ -317,7 +318,7 @@ func fetchReportWriteBucket(tx kvdb.RwTx, chainHash chainhash.Hash,
 	}
 
 	var chanPointBuf bytes.Buffer
-	if err := writeOutpoint(&chanPointBuf, outPoint); err != nil {
+	if err := graphdb.WriteOutpoint(&chanPointBuf, outPoint); err != nil {
 		return nil, err
 	}
 
@@ -341,7 +342,7 @@ func fetchReportReadBucket(tx kvdb.RTx, chainHash chainhash.Hash,
 	// With the bucket for the node and chain fetched, we can now go down
 	// another level, for the channel itself.
 	var chanPointBuf bytes.Buffer
-	if err := writeOutpoint(&chanPointBuf, outPoint); err != nil {
+	if err := graphdb.WriteOutpoint(&chanPointBuf, outPoint); err != nil {
 		return nil, err
 	}
 

channeldb/reports_test.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/wire"
+	graphdb "github.com/lightningnetwork/lnd/graph/db"
 	"github.com/lightningnetwork/lnd/kvdb"
 	"github.com/stretchr/testify/require"
 )
@@ -137,7 +138,7 @@ func TestFetchChannelWriteBucket(t *testing.T) {
 		error) {
 
 		var chanPointBuf bytes.Buffer
-		err := writeOutpoint(&chanPointBuf, &testChanPoint1)
+		err := graphdb.WriteOutpoint(&chanPointBuf, &testChanPoint1)
 		require.NoError(t, err)
 
 		return chainHash.CreateBucketIfNotExists(chanPointBuf.Bytes())

graph/db/codec.go

@@ -1,8 +1,39 @@
 package graphdb
 
-import "encoding/binary"
+import (
+	"encoding/binary"
+	"io"
+
+	"github.com/btcsuite/btcd/wire"
+)
 
 var (
 	// byteOrder defines the preferred byte order, which is Big Endian.
 	byteOrder = binary.BigEndian
 )
+
+// WriteOutpoint writes an outpoint to the passed writer using the minimal
+// amount of bytes possible.
+func WriteOutpoint(w io.Writer, o *wire.OutPoint) error {
+	if _, err := w.Write(o.Hash[:]); err != nil {
+		return err
+	}
+	if err := binary.Write(w, byteOrder, o.Index); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// ReadOutpoint reads an outpoint from the passed reader that was previously
+// written using the WriteOutpoint struct.
+func ReadOutpoint(r io.Reader, o *wire.OutPoint) error {
+	if _, err := io.ReadFull(r, o.Hash[:]); err != nil {
+		return err
+	}
+	if err := binary.Read(r, byteOrder, &o.Index); err != nil {
+		return err
+	}
+
+	return nil
+}