routing: track unifiedPolicyEdge

Preparation so that we can have the inbound fee available
in addition to the outgoing policy.

routing/heap.go

@@ -3,7 +3,6 @@ package routing
 import (
 	"container/heap"
 
-	"github.com/lightningnetwork/lnd/channeldb/models"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/routing/route"
 )
@@ -39,7 +38,7 @@ type nodeWithDist struct {
 	weight int64
 
 	// nextHop is the edge this route comes from.
-	nextHop *models.CachedEdgePolicy
+	nextHop *unifiedEdge
 
 	// routingInfoSize is the total size requirement for the payloads field
 	// in the onion packet from this hop towards the final destination.

routing/pathfind.go

@@ -11,7 +11,6 @@ import (
 	"github.com/btcsuite/btcd/btcutil"
 	sphinx "github.com/lightningnetwork/lightning-onion"
 	"github.com/lightningnetwork/lnd/channeldb"
-	"github.com/lightningnetwork/lnd/channeldb/models"
 	"github.com/lightningnetwork/lnd/feature"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/record"
@@ -50,7 +49,7 @@ const (
 type pathFinder = func(g *graphParams, r *RestrictParams,
 	cfg *PathFindingConfig, source, target route.Vertex,
 	amt lnwire.MilliSatoshi, timePref float64, finalHtlcExpiry int32) (
-	[]*models.CachedEdgePolicy, float64, error)
+	[]*unifiedEdge, float64, error)
 
 var (
 	// DefaultEstimator is the default estimator used for computing
@@ -126,7 +125,7 @@ type finalHopParams struct {
 // NOTE: If a non-nil blinded path is provided it is assumed to have been
 // validated by the caller.
 func newRoute(sourceVertex route.Vertex,
-	pathEdges []*models.CachedEdgePolicy, currentHeight uint32,
+	pathEdges []*unifiedEdge, currentHeight uint32,
 	finalHop finalHopParams, blindedPath *sphinx.BlindedPath) (
 	*route.Route, error) {
 
@@ -149,7 +148,7 @@ func newRoute(sourceVertex route.Vertex,
 	for i := pathLength - 1; i >= 0; i-- {
 		// Now we'll start to calculate the items within the per-hop
 		// payload for the hop this edge is leading to.
-		edge := pathEdges[i]
+		edge := pathEdges[i].policy
 
 		// We'll calculate the amounts, timelocks, and fees for each hop
 		// in the route. The base case is the final hop which includes
@@ -245,13 +244,15 @@ func newRoute(sourceVertex route.Vertex,
 			// and its policy for the outgoing channel. This policy
 			// is stored as part of the incoming channel of
 			// the next hop.
-			fee = pathEdges[i+1].ComputeFee(amtToForward)
+			fee = pathEdges[i+1].policy.ComputeFee(amtToForward)
 
 			// We'll take the total timelock of the preceding hop as
 			// the outgoing timelock or this hop. Then we'll
 			// increment the total timelock incurred by this hop.
 			outgoingTimeLock = totalTimeLock
-			totalTimeLock += uint32(pathEdges[i+1].TimeLockDelta)
+			totalTimeLock += uint32(
+				pathEdges[i+1].policy.TimeLockDelta,
+			)
 		}
 
 		// Since we're traversing the path backwards atm, we prepend
@@ -504,7 +505,7 @@ func getOutgoingBalance(node route.Vertex, outgoingChans map[uint64]struct{},
 // available bandwidth.
 func findPath(g *graphParams, r *RestrictParams, cfg *PathFindingConfig,
 	source, target route.Vertex, amt lnwire.MilliSatoshi, timePref float64,
-	finalHtlcExpiry int32) ([]*models.CachedEdgePolicy, float64, error) {
+	finalHtlcExpiry int32) ([]*unifiedEdge, float64, error) {
 
 	// Pathfinding can be a significant portion of the total payment
 	// latency, especially on low-powered devices. Log several metrics to
@@ -859,7 +860,7 @@ func findPath(g *graphParams, r *RestrictParams, cfg *PathFindingConfig,
 			amountToReceive: amountToReceive,
 			incomingCltv:    incomingCltv,
 			probability:     probability,
-			nextHop:         edge.policy,
+			nextHop:         edge,
 			routingInfoSize: routingInfoSize,
 		}
 		distance[fromVertex] = withDist
@@ -1009,7 +1010,7 @@ func findPath(g *graphParams, r *RestrictParams, cfg *PathFindingConfig,
 
 	// Use the distance map to unravel the forward path from source to
 	// target.
-	var pathEdges []*models.CachedEdgePolicy
+	var pathEdges []*unifiedEdge
 	currentNode := source
 	for {
 		// Determine the next hop forward using the next map.
@@ -1024,7 +1025,7 @@ func findPath(g *graphParams, r *RestrictParams, cfg *PathFindingConfig,
 		pathEdges = append(pathEdges, currentNodeWithDist.nextHop)
 
 		// Advance current node.
-		currentNode = currentNodeWithDist.nextHop.ToNodePubKey()
+		currentNode = currentNodeWithDist.nextHop.policy.ToNodePubKey()
 
 		// Check stop condition at the end of this loop. This prevents
 		// breaking out too soon for self-payments that have target set
@@ -1045,7 +1046,7 @@ func findPath(g *graphParams, r *RestrictParams, cfg *PathFindingConfig,
 	// route construction does not care where the features are actually
 	// taken from. In the future we may wish to do route construction within
 	// findPath, and avoid using ChannelEdgePolicy altogether.
-	pathEdges[len(pathEdges)-1].ToNodeFeatures = features
+	pathEdges[len(pathEdges)-1].policy.ToNodeFeatures = features
 
 	log.Debugf("Found route: probability=%v, hops=%v, fee=%v",
 		distance[source].probability, len(pathEdges),

routing/pathfind_test.go

@@ -1225,7 +1225,7 @@ func runPathFindingWithAdditionalEdges(t *testing.T, useCache bool) {
 	}
 
 	find := func(r *RestrictParams) (
-		[]*models.CachedEdgePolicy, error) {
+		[]*unifiedEdge, error) {
 
 		return dbFindPath(
 			graph.graph, additionalEdges, &mockBandwidthHints{},
@@ -1437,7 +1437,7 @@ func runPathFindingWithRedundantAdditionalEdges(t *testing.T, useCache bool) {
 	require.NoError(t, err, "unable to find path to bob")
 	require.Len(t, path, 1)
 
-	require.Equal(t, realChannelID, path[0].ChannelID,
+	require.Equal(t, realChannelID, path[0].policy.ChannelID,
 		"additional edge for known edge wasn't ignored")
 }
 
@@ -1723,8 +1723,17 @@ func TestNewRoute(t *testing.T) {
 		}
 
 		t.Run(testCase.name, func(t *testing.T) {
+			var unifiedHops []*unifiedEdge
+			for _, hop := range testCase.hops {
+				unifiedHops = append(unifiedHops,
+					&unifiedEdge{
+						policy: hop,
+					},
+				)
+			}
+
 			route, err := newRoute(
-				sourceVertex, testCase.hops, startingHeight,
+				sourceVertex, unifiedHops, startingHeight,
 				finalHopParams{
 					amt:         testCase.paymentAmount,
 					totalAmt:    testCase.paymentAmount,
@@ -1864,7 +1873,7 @@ func runDestTLVGraphFallback(t *testing.T, useCache bool) {
 	require.NoError(t, err, "unable to fetch source node")
 
 	find := func(r *RestrictParams,
-		target route.Vertex) ([]*models.CachedEdgePolicy, error) {
+		target route.Vertex) ([]*unifiedEdge, error) {
 
 		return dbFindPath(
 			ctx.graph, nil, &mockBandwidthHints{},
@@ -2522,7 +2531,7 @@ func TestPathFindSpecExample(t *testing.T) {
 }
 
 func assertExpectedPath(t *testing.T, aliasMap map[string]route.Vertex,
-	path []*models.CachedEdgePolicy, nodeAliases ...string) {
+	path []*unifiedEdge, nodeAliases ...string) {
 
 	if len(path) != len(nodeAliases) {
 		t.Fatalf("number of hops=(%v) and number of aliases=(%v) do "+
@@ -2530,9 +2539,10 @@ func assertExpectedPath(t *testing.T, aliasMap map[string]route.Vertex,
 	}
 
 	for i, hop := range path {
-		if hop.ToNodePubKey() != aliasMap[nodeAliases[i]] {
+		if hop.policy.ToNodePubKey() != aliasMap[nodeAliases[i]] {
 			t.Fatalf("expected %v to be pos #%v in hop, instead "+
-				"%v was", nodeAliases[i], i, hop.ToNodePubKey())
+				"%v was", nodeAliases[i], i,
+				hop.policy.ToNodePubKey())
 		}
 	}
 }
@@ -2606,10 +2616,10 @@ func runRestrictOutgoingChannel(t *testing.T, useCache bool) {
 
 	// Assert that the route starts with channel chanSourceB1, in line with
 	// the specified restriction.
-	if path[0].ChannelID != chanSourceB1 {
+	if path[0].policy.ChannelID != chanSourceB1 {
 		t.Fatalf("expected route to pass through channel %v, "+
 			"but channel %v was selected instead", chanSourceB1,
-			path[0].ChannelID)
+			path[0].policy.ChannelID)
 	}
 
 	// If a direct channel to target is allowed as well, that channel is
@@ -2619,7 +2629,7 @@ func runRestrictOutgoingChannel(t *testing.T, useCache bool) {
 	}
 	path, err = ctx.findPath(target, paymentAmt)
 	require.NoError(t, err, "unable to find path")
-	if path[0].ChannelID != chanSourceTarget {
+	if path[0].policy.ChannelID != chanSourceTarget {
 		t.Fatalf("expected route to pass through channel %v",
 			chanSourceTarget)
 	}
@@ -2658,10 +2668,10 @@ func runRestrictLastHop(t *testing.T, useCache bool) {
 	ctx.restrictParams.LastHop = &lastHop
 	path, err := ctx.findPath(target, paymentAmt)
 	require.NoError(t, err, "unable to find path")
-	if path[0].ChannelID != 3 {
+	if path[0].policy.ChannelID != 3 {
 		t.Fatalf("expected route to pass through channel 3, "+
 			"but channel %v was selected instead",
-			path[0].ChannelID)
+			path[0].policy.ChannelID)
 	}
 }
 
@@ -2941,10 +2951,10 @@ func testProbabilityRouting(t *testing.T, useCache bool,
 	}
 
 	// Assert that the route passes through the expected channel.
-	if path[1].ChannelID != expectedChan {
+	if path[1].policy.ChannelID != expectedChan {
 		t.Fatalf("expected route to pass through channel %v, "+
 			"but channel %v was selected instead", expectedChan,
-			path[1].ChannelID)
+			path[1].policy.ChannelID)
 	}
 }
 
@@ -3005,10 +3015,10 @@ func runEqualCostRouteSelection(t *testing.T, useCache bool) {
 		t.Fatal(err)
 	}
 
-	if path[1].ChannelID != 2 {
+	if path[1].policy.ChannelID != 2 {
 		t.Fatalf("expected route to pass through channel %v, "+
 			"but channel %v was selected instead", 2,
-			path[1].ChannelID)
+			path[1].policy.ChannelID)
 	}
 }
 
@@ -3168,7 +3178,7 @@ func (c *pathFindingTestContext) aliasFromKey(pubKey route.Vertex) string {
 }
 
 func (c *pathFindingTestContext) findPath(target route.Vertex,
-	amt lnwire.MilliSatoshi) ([]*models.CachedEdgePolicy,
+	amt lnwire.MilliSatoshi) ([]*unifiedEdge,
 	error) {
 
 	return dbFindPath(
@@ -3177,7 +3187,7 @@ func (c *pathFindingTestContext) findPath(target route.Vertex,
 	)
 }
 
-func (c *pathFindingTestContext) assertPath(path []*models.CachedEdgePolicy,
+func (c *pathFindingTestContext) assertPath(path []*unifiedEdge,
 	expected []uint64) {
 
 	if len(path) != len(expected) {
@@ -3186,9 +3196,10 @@ func (c *pathFindingTestContext) assertPath(path []*models.CachedEdgePolicy,
 	}
 
 	for i, edge := range path {
-		if edge.ChannelID != expected[i] {
+		if edge.policy.ChannelID != expected[i] {
 			c.t.Fatalf("expected hop %v to be channel %v, "+
-				"but got %v", i, expected[i], edge.ChannelID)
+				"but got %v", i, expected[i],
+				edge.policy.ChannelID)
 		}
 	}
 }
@@ -3200,7 +3211,7 @@ func dbFindPath(graph *channeldb.ChannelGraph,
 	bandwidthHints bandwidthHints,
 	r *RestrictParams, cfg *PathFindingConfig,
 	source, target route.Vertex, amt lnwire.MilliSatoshi, timePref float64,
-	finalHtlcExpiry int32) ([]*models.CachedEdgePolicy, error) {
+	finalHtlcExpiry int32) ([]*unifiedEdge, error) {
 
 	sourceNode, err := graph.SourceNode()
 	if err != nil {
@@ -3351,11 +3362,11 @@ func TestBlindedRouteConstruction(t *testing.T) {
 	carolDaveEdge := blindedEdges[carolVertex][0]
 	daveEveEdge := blindedEdges[daveBlindedVertex][0]
 
-	edges := []*models.CachedEdgePolicy{
-		aliceBobEdge,
-		bobCarolEdge,
-		carolDaveEdge.EdgePolicy(),
-		daveEveEdge.EdgePolicy(),
+	edges := []*unifiedEdge{
+		{policy: aliceBobEdge},
+		{policy: bobCarolEdge},
+		{policy: carolDaveEdge.EdgePolicy()},
+		{policy: daveEveEdge.EdgePolicy()},
 	}
 
 	// Total timelock for the route should include:

routing/payment_session_test.go

@@ -212,7 +212,7 @@ func TestRequestRoute(t *testing.T) {
 	// Override pathfinder with a mock.
 	session.pathFinder = func(_ *graphParams, r *RestrictParams,
 		_ *PathFindingConfig, _, _ route.Vertex, _ lnwire.MilliSatoshi,
-		_ float64, _ int32) ([]*models.CachedEdgePolicy, float64,
+		_ float64, _ int32) ([]*unifiedEdge, float64,
 		error) {
 
 		// We expect find path to receive a cltv limit excluding the
@@ -221,14 +221,16 @@ func TestRequestRoute(t *testing.T) {
 			t.Fatal("wrong cltv limit")
 		}
 
-		path := []*models.CachedEdgePolicy{
+		path := []*unifiedEdge{
 			{
-				ToNodePubKey: func() route.Vertex {
-					return route.Vertex{}
+				policy: &models.CachedEdgePolicy{
+					ToNodePubKey: func() route.Vertex {
+						return route.Vertex{}
+					},
+					ToNodeFeatures: lnwire.NewFeatureVector(
+						nil, nil,
+					),
 				},
-				ToNodeFeatures: lnwire.NewFeatureVector(
-					nil, nil,
-				),
 			},
 		}
 

routing/router.go

@@ -3218,14 +3218,14 @@ func getRouteUnifiers(source route.Vertex, hops []route.Vertex,
 // including fees, to send the payment.
 func getPathEdges(source route.Vertex, receiverAmt lnwire.MilliSatoshi,
 	unifiers []*edgeUnifier, bandwidthHints *bandwidthManager,
-	hops []route.Vertex) ([]*models.CachedEdgePolicy,
+	hops []route.Vertex) ([]*unifiedEdge,
 	lnwire.MilliSatoshi, error) {
 
 	// Now that we arrived at the start of the route and found out the route
 	// total amount, we make a forward pass. Because the amount may have
 	// been increased in the backward pass, fees need to be recalculated and
 	// amount ranges re-checked.
-	var pathEdges []*models.CachedEdgePolicy
+	var pathEdges []*unifiedEdge
 	for i, unifier := range unifiers {
 		edge := unifier.getEdge(receiverAmt, bandwidthHints)
 		if edge == nil {
@@ -3247,7 +3247,7 @@ func getPathEdges(source route.Vertex, receiverAmt lnwire.MilliSatoshi,
 			)
 		}
 
-		pathEdges = append(pathEdges, edge.policy)
+		pathEdges = append(pathEdges, edge)
 	}
 
 	return pathEdges, receiverAmt, nil

routing/router_test.go

@@ -2450,8 +2450,8 @@ func TestFindPathFeeWeighting(t *testing.T) {
 	if len(path) != 1 {
 		t.Fatalf("expected path length of 1, instead was: %v", len(path))
 	}
-	if path[0].ToNodePubKey() != ctx.aliases["luoji"] {
-		t.Fatalf("wrong node: %v", path[0].ToNodePubKey())
+	if path[0].policy.ToNodePubKey() != ctx.aliases["luoji"] {
+		t.Fatalf("wrong node: %v", path[0].policy.ToNodePubKey())
 	}
 }