channeldb+discovery: fetch timestamps from DB if required

channeldb/graph.go

@@ -2143,6 +2143,23 @@ func (c *ChannelGraph) FilterKnownChanIDs(chanIDs []uint64) ([]uint64, error) {
 	return newChanIDs, nil
 }
 
+// ChannelUpdateInfo couples the SCID of a channel with the timestamps of the
+// latest received channel updates for the channel.
+type ChannelUpdateInfo struct {
+	// ShortChannelID is the SCID identifier of the channel.
+	ShortChannelID lnwire.ShortChannelID
+
+	// Node1UpdateTimestamp is the timestamp of the latest received update
+	// from the node 1 channel peer. This will be set to zero time if no
+	// update has yet been received from this node.
+	Node1UpdateTimestamp time.Time
+
+	// Node2UpdateTimestamp is the timestamp of the latest received update
+	// from the node 2 channel peer. This will be set to zero time if no
+	// update has yet been received from this node.
+	Node2UpdateTimestamp time.Time
+}
+
 // BlockChannelRange represents a range of channels for a given block height.
 type BlockChannelRange struct {
 	// Height is the height of the block all of the channels below were
@@ -2151,17 +2168,20 @@ type BlockChannelRange struct {
 
 	// Channels is the list of channels identified by their short ID
 	// representation known to us that were included in the block height
-	// above.
+	// above. The list may include channel update timestamp information if
-	Channels []lnwire.ShortChannelID
+	// requested.
+	Channels []ChannelUpdateInfo
 }
 
 // FilterChannelRange returns the channel ID's of all known channels which were
 // mined in a block height within the passed range. The channel IDs are grouped
 // by their common block height. This method can be used to quickly share with a
 // peer the set of channels we know of within a particular range to catch them
-// up after a period of time offline.
+// up after a period of time offline. If withTimestamps is true then the
+// timestamp info of the latest received channel update messages of the channel
+// will be included in the response.
 func (c *ChannelGraph) FilterChannelRange(startHeight,
-	endHeight uint32) ([]BlockChannelRange, error) {
+	endHeight uint32, withTimestamps bool) ([]BlockChannelRange, error) {
 
 	startChanID := &lnwire.ShortChannelID{
 		BlockHeight: startHeight,
@@ -2180,7 +2200,7 @@ func (c *ChannelGraph) FilterChannelRange(startHeight,
 	byteOrder.PutUint64(chanIDStart[:], startChanID.ToUint64())
 	byteOrder.PutUint64(chanIDEnd[:], endChanID.ToUint64())
 
-	var channelsPerBlock map[uint32][]lnwire.ShortChannelID
+	var channelsPerBlock map[uint32][]ChannelUpdateInfo
 	err := kvdb.View(c.db, func(tx kvdb.RTx) error {
 		edges := tx.ReadBucket(edgeBucket)
 		if edges == nil {
@@ -2212,14 +2232,60 @@ func (c *ChannelGraph) FilterChannelRange(startHeight,
 			// we'll add it to our returned set.
 			rawCid := byteOrder.Uint64(k)
 			cid := lnwire.NewShortChanIDFromInt(rawCid)
+
+			chanInfo := ChannelUpdateInfo{
+				ShortChannelID: cid,
+			}
+
+			if !withTimestamps {
 				channelsPerBlock[cid.BlockHeight] = append(
-				channelsPerBlock[cid.BlockHeight], cid,
+					channelsPerBlock[cid.BlockHeight],
+					chanInfo,
+				)
+
+				continue
+			}
+
+			node1Key, node2Key := computeEdgePolicyKeys(&edgeInfo)
+
+			rawPolicy := edges.Get(node1Key)
+			if len(rawPolicy) != 0 {
+				r := bytes.NewReader(rawPolicy)
+
+				edge, err := deserializeChanEdgePolicyRaw(r)
+				if err != nil && !errors.Is(
+					err, ErrEdgePolicyOptionalFieldNotFound,
+				) {
+
+					return err
+				}
+
+				chanInfo.Node1UpdateTimestamp = edge.LastUpdate
+			}
+
+			rawPolicy = edges.Get(node2Key)
+			if len(rawPolicy) != 0 {
+				r := bytes.NewReader(rawPolicy)
+
+				edge, err := deserializeChanEdgePolicyRaw(r)
+				if err != nil && !errors.Is(
+					err, ErrEdgePolicyOptionalFieldNotFound,
+				) {
+
+					return err
+				}
+
+				chanInfo.Node2UpdateTimestamp = edge.LastUpdate
+			}
+
+			channelsPerBlock[cid.BlockHeight] = append(
+				channelsPerBlock[cid.BlockHeight], chanInfo,
 			)
 		}
 
 		return nil
 	}, func() {
-		channelsPerBlock = make(map[uint32][]lnwire.ShortChannelID)
+		channelsPerBlock = make(map[uint32][]ChannelUpdateInfo)
 	})
 
 	switch {
@@ -3118,6 +3184,24 @@ func (c *ChannelGraph) FetchOtherNode(tx kvdb.RTx,
 	return targetNode, err
 }
 
+// computeEdgePolicyKeys is a helper function that can be used to compute the
+// keys used to index the channel edge policy info for the two nodes of the
+// edge. The keys for node 1 and node 2 are returned respectively.
+func computeEdgePolicyKeys(info *models.ChannelEdgeInfo) ([]byte, []byte) {
+	var (
+		node1Key [33 + 8]byte
+		node2Key [33 + 8]byte
+	)
+
+	copy(node1Key[:], info.NodeKey1Bytes[:])
+	copy(node2Key[:], info.NodeKey2Bytes[:])
+
+	byteOrder.PutUint64(node1Key[33:], info.ChannelID)
+	byteOrder.PutUint64(node2Key[33:], info.ChannelID)
+
+	return node1Key[:], node2Key[:]
+}
+
 // FetchChannelEdgesByOutpoint attempts to lookup the two directed edges for
 // the channel identified by the funding outpoint. If the channel can't be
 // found, then ErrEdgeNotFound is returned. A struct which houses the general

channeldb/graph_test.go

@@ -27,6 +27,7 @@ import (
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/routing/route"
 	"github.com/stretchr/testify/require"
+	"golang.org/x/exp/rand"
 )
 
 var (
@@ -2045,7 +2046,7 @@ func TestFilterChannelRange(t *testing.T) {
 
 	// If we try to filter a channel range before we have any channels
 	// inserted, we should get an empty slice of results.
-	resp, err := graph.FilterChannelRange(10, 100)
+	resp, err := graph.FilterChannelRange(10, 100, false)
 	require.NoError(t, err)
 	require.Empty(t, resp)
 
@@ -2054,7 +2055,41 @@ func TestFilterChannelRange(t *testing.T) {
 	startHeight := uint32(100)
 	endHeight := startHeight
 	const numChans = 10
-	channelRanges := make([]BlockChannelRange, 0, numChans/2)
+
+	var (
+		channelRanges = make(
+			[]BlockChannelRange, 0, numChans/2,
+		)
+		channelRangesWithTimestamps = make(
+			[]BlockChannelRange, 0, numChans/2,
+		)
+	)
+
+	updateTimeSeed := int64(1)
+	maybeAddPolicy := func(chanID uint64, node *LightningNode,
+		node2 bool) time.Time {
+
+		var chanFlags lnwire.ChanUpdateChanFlags
+		if node2 {
+			chanFlags = lnwire.ChanUpdateDirection
+		}
+
+		var updateTime time.Time
+		if rand.Int31n(2) == 0 {
+			updateTime = time.Unix(updateTimeSeed, 0)
+			err = graph.UpdateEdgePolicy(&models.ChannelEdgePolicy{
+				ToNode:       node.PubKeyBytes,
+				ChannelFlags: chanFlags,
+				ChannelID:    chanID,
+				LastUpdate:   updateTime,
+			})
+			require.NoError(t, err)
+		}
+		updateTimeSeed++
+
+		return updateTime
+	}
+
 	for i := 0; i < numChans/2; i++ {
 		chanHeight := endHeight
 		channel1, chanID1 := createEdge(
@@ -2069,8 +2104,37 @@ func TestFilterChannelRange(t *testing.T) {
 
 		channelRanges = append(channelRanges, BlockChannelRange{
 			Height: chanHeight,
-			Channels: []lnwire.ShortChannelID{chanID1, chanID2},
+			Channels: []ChannelUpdateInfo{
+				{ShortChannelID: chanID1},
+				{ShortChannelID: chanID2},
+			},
 		})
+
+		var (
+			time1 = maybeAddPolicy(channel1.ChannelID, node1, false)
+			time2 = maybeAddPolicy(channel1.ChannelID, node2, true)
+			time3 = maybeAddPolicy(channel2.ChannelID, node1, false)
+			time4 = maybeAddPolicy(channel2.ChannelID, node2, true)
+		)
+
+		channelRangesWithTimestamps = append(
+			channelRangesWithTimestamps, BlockChannelRange{
+				Height: chanHeight,
+				Channels: []ChannelUpdateInfo{
+					{
+						ShortChannelID:       chanID1,
+						Node1UpdateTimestamp: time1,
+						Node2UpdateTimestamp: time2,
+					},
+					{
+						ShortChannelID:       chanID2,
+						Node1UpdateTimestamp: time3,
+						Node2UpdateTimestamp: time4,
+					},
+				},
+			},
+		)
+
 		endHeight += 10
 	}
 
@@ -2084,6 +2148,8 @@ func TestFilterChannelRange(t *testing.T) {
 		endHeight   uint32
 
 		resp          []BlockChannelRange
+		expStartIndex int
+		expEndIndex   int
 	}{
 		// If we query for the entire range, then we should get the same
 		// set of short channel IDs back.
@@ -2093,6 +2159,8 @@ func TestFilterChannelRange(t *testing.T) {
 			endHeight:   endHeight,
 
 			resp:          channelRanges,
+			expStartIndex: 0,
+			expEndIndex:   len(channelRanges),
 		},
 
 		// If we query for a range of channels right before our range,
@@ -2111,6 +2179,8 @@ func TestFilterChannelRange(t *testing.T) {
 			endHeight:   endHeight - 10,
 
 			resp:          channelRanges[4:],
+			expStartIndex: 4,
+			expEndIndex:   len(channelRanges),
 		},
 
 		// If we query for just the first height, we should only get a
@@ -2121,6 +2191,8 @@ func TestFilterChannelRange(t *testing.T) {
 			endHeight:   startHeight,
 
 			resp:          channelRanges[:1],
+			expStartIndex: 0,
+			expEndIndex:   1,
 		},
 
 		{
@@ -2129,19 +2201,44 @@ func TestFilterChannelRange(t *testing.T) {
 			endHeight:   endHeight - 10,
 
 			resp:          channelRanges[1:5],
+			expStartIndex: 1,
+			expEndIndex:   5,
 		},
 	}
+
 	for _, test := range tests {
 		test := test
 
 		t.Run(test.name, func(t *testing.T) {
 			t.Parallel()
 
+			// First, do the query without requesting timestamps.
 			resp, err := graph.FilterChannelRange(
-				test.startHeight, test.endHeight,
+				test.startHeight, test.endHeight, false,
 			)
 			require.NoError(t, err)
-			require.Equal(t, test.resp, resp)
+
+			expRes := channelRanges[test.expStartIndex:test.expEndIndex] //nolint:lll
+
+			if len(expRes) == 0 {
+				require.Nil(t, resp)
+			} else {
+				require.Equal(t, expRes, resp)
+			}
+
+			// Now, query the timestamps as well.
+			resp, err = graph.FilterChannelRange(
+				test.startHeight, test.endHeight, true,
+			)
+			require.NoError(t, err)
+
+			expRes = channelRangesWithTimestamps[test.expStartIndex:test.expEndIndex] //nolint:lll
+
+			if len(expRes) == 0 {
+				require.Nil(t, resp)
+			} else {
+				require.Equal(t, expRes, resp)
+			}
 		})
 	}
 }

discovery/chan_series.go

@@ -229,7 +229,7 @@ func (c *ChanSeries) FilterKnownChanIDs(chain chainhash.Hash,
 func (c *ChanSeries) FilterChannelRange(chain chainhash.Hash,
 	startHeight, endHeight uint32) ([]channeldb.BlockChannelRange, error) {
 
-	return c.graph.FilterChannelRange(startHeight, endHeight)
+	return c.graph.FilterChannelRange(startHeight, endHeight, false)
 }
 
 // FetchChanAnns returns a full set of channel announcements as well as their

discovery/syncer.go

@@ -11,6 +11,7 @@ import (
 	"time"
 
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
+	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/lnpeer"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"golang.org/x/time/rate"
@@ -1044,7 +1045,7 @@ func (g *GossipSyncer) replyChanRangeQuery(query *lnwire.QueryChannelRange) erro
 	// this as there's a transport message size limit which we'll need to
 	// adhere to. We also need to make sure all of our replies cover the
 	// expected range of the query.
-	sendReplyForChunk := func(channelChunk []lnwire.ShortChannelID,
+	sendReplyForChunk := func(channelChunk []channeldb.ChannelUpdateInfo,
 		firstHeight, lastHeight uint32, finalChunk bool) error {
 
 		// The number of blocks contained in the current chunk (the
@@ -1057,20 +1058,25 @@ func (g *GossipSyncer) replyChanRangeQuery(query *lnwire.QueryChannelRange) erro
 			complete = 1
 		}
 
+		scids := make([]lnwire.ShortChannelID, len(channelChunk))
+		for i, info := range channelChunk {
+			scids[i] = info.ShortChannelID
+		}
+
 		return g.cfg.sendToPeerSync(&lnwire.ReplyChannelRange{
 			ChainHash:        query.ChainHash,
 			NumBlocks:        numBlocks,
 			FirstBlockHeight: firstHeight,
 			Complete:         complete,
 			EncodingType:     g.cfg.encodingType,
-			ShortChanIDs:     channelChunk,
+			ShortChanIDs:     scids,
 		})
 	}
 
 	var (
 		firstHeight  = query.FirstBlockHeight
 		lastHeight   uint32
-		channelChunk []lnwire.ShortChannelID
+		channelChunk []channeldb.ChannelUpdateInfo
 	)
 	for _, channelRange := range channelRanges {
 		channels := channelRange.Channels
@@ -1118,8 +1124,10 @@ func (g *GossipSyncer) replyChanRangeQuery(query *lnwire.QueryChannelRange) erro
 		// Sort the chunk once again if we had to shuffle it.
 		if exceedsChunkSize {
 			sort.Slice(channelChunk, func(i, j int) bool {
-				return channelChunk[i].ToUint64() <
+				id1 := channelChunk[i].ShortChannelID.ToUint64()
-					channelChunk[j].ToUint64()
+				id2 := channelChunk[j].ShortChannelID.ToUint64()
+
+				return id1 < id2
 			})
 		}
 	}

discovery/syncer_test.go

@@ -103,10 +103,13 @@ func (m *mockChannelGraphTimeSeries) FilterChannelRange(chain chainhash.Hash,
 	m.filterRangeReqs <- filterRangeReq{startHeight, endHeight}
 	reply := <-m.filterRangeResp
 
-	channelsPerBlock := make(map[uint32][]lnwire.ShortChannelID)
+	channelsPerBlock := make(map[uint32][]channeldb.ChannelUpdateInfo)
 	for _, cid := range reply {
 		channelsPerBlock[cid.BlockHeight] = append(
-			channelsPerBlock[cid.BlockHeight], cid,
+			channelsPerBlock[cid.BlockHeight],
+			channeldb.ChannelUpdateInfo{
+				ShortChannelID: cid,
+			},
 		)
 	}
 
@@ -119,16 +122,21 @@ func (m *mockChannelGraphTimeSeries) FilterChannelRange(chain chainhash.Hash,
 		return blocks[i] < blocks[j]
 	})
 
-	channelRanges := make([]channeldb.BlockChannelRange, 0, len(channelsPerBlock))
+	channelRanges := make(
+		[]channeldb.BlockChannelRange, 0, len(channelsPerBlock),
+	)
 	for _, block := range blocks {
-		channelRanges = append(channelRanges, channeldb.BlockChannelRange{
+		channelRanges = append(
+			channelRanges, channeldb.BlockChannelRange{
 				Height:   block,
 				Channels: channelsPerBlock[block],
-		})
+			},
+		)
 	}
 
 	return channelRanges, nil
 }
+
 func (m *mockChannelGraphTimeSeries) FetchChanAnns(chain chainhash.Hash,
 	shortChanIDs []lnwire.ShortChannelID) ([]lnwire.Message, error) {