multi: set the InboundFee on ChannelEdgePolicy

In this commit, we make sure to set the new field wherever appropriate.
This will be any place where the ChannelEdgePolicy is constructed other
than its disk deserialisation.

Author: ellemouton

discovery/gossiper.go

@@ -3260,6 +3260,26 @@ func (d *AuthenticatedGossiper) handleChanUpdate(ctx context.Context,
 		ExtraOpaqueData:           upd.ExtraOpaqueData,
 	}
 
+	// Extract the inbound fee from the ExtraOpaqueData, if present.
+	//
+	// TODO(elle): this can be removed once we define the optional TLV
+	// field on the lnwire.ChannelUpdate itself.
+	var inboundFee lnwire.Fee
+	typeMap, err := upd.ExtraOpaqueData.ExtractRecords(&inboundFee)
+	if err != nil {
+		rErr := fmt.Errorf("%w: %w", graphdb.ErrParsingExtraTLVBytes,
+			err)
+
+		log.Error(rErr)
+		nMsg.err <- rErr
+		return nil, false
+	}
+
+	val, ok := typeMap[lnwire.FeeRecordType]
+	if ok && val == nil {
+		update.InboundFee = fn.Some(inboundFee)
+	}
+
 	if err := d.cfg.Graph.UpdateEdge(update, ops...); err != nil {
 		if graph.IsError(
 			err, graph.ErrOutdated,

graph/builder.go

@@ -11,6 +11,7 @@ import (
 	"github.com/go-errors/errors"
 	"github.com/lightningnetwork/lnd/batch"
 	"github.com/lightningnetwork/lnd/chainntnfs"
+	"github.com/lightningnetwork/lnd/fn/v2"
 	graphdb "github.com/lightningnetwork/lnd/graph/db"
 	"github.com/lightningnetwork/lnd/graph/db/models"
 	"github.com/lightningnetwork/lnd/lnutils"
@@ -943,7 +944,7 @@ func (b *Builder) ApplyChannelUpdate(msg *lnwire.ChannelUpdate1) bool {
 		return false
 	}
 
-	err = b.UpdateEdge(&models.ChannelEdgePolicy{
+	update := &models.ChannelEdgePolicy{
 		SigBytes:                  msg.Signature.ToSignatureBytes(),
 		ChannelID:                 msg.ShortChannelID.ToUint64(),
 		LastUpdate:                time.Unix(int64(msg.Timestamp), 0),
@@ -955,7 +956,25 @@ func (b *Builder) ApplyChannelUpdate(msg *lnwire.ChannelUpdate1) bool {
 		FeeBaseMSat:               lnwire.MilliSatoshi(msg.BaseFee),
 		FeeProportionalMillionths: lnwire.MilliSatoshi(msg.FeeRate),
 		ExtraOpaqueData:           msg.ExtraOpaqueData,
-	})
+	}
+
+	// Extract the inbound fee from the ExtraOpaqueData, if present.
+	//
+	// TODO(elle): this can be removed once we define the optional TLV
+	// field on the lnwire.ChannelUpdate itself.
+	var inboundFee lnwire.Fee
+	typeMap, err := update.ExtraOpaqueData.ExtractRecords(&inboundFee)
+	if err != nil {
+		log.Errorf("%v: %v", graphdb.ErrParsingExtraTLVBytes, err)
+		return false
+	}
+
+	val, ok := typeMap[lnwire.FeeRecordType]
+	if ok && val == nil {
+		update.InboundFee = fn.Some(inboundFee)
+	}
+
+	err = b.UpdateEdge(update)
 	if err != nil && !IsError(err, ErrIgnored, ErrOutdated) {
 		log.Errorf("Unable to apply channel update: %v", err)
 		return false

graph/notifications_test.go

@@ -121,6 +121,7 @@ func randEdgePolicy(chanID *lnwire.ShortChannelID,
 		FeeBaseMSat:               lnwire.MilliSatoshi(prand.Int31()),
 		FeeProportionalMillionths: lnwire.MilliSatoshi(prand.Int31()),
 		ToNode:                    node.PubKeyBytes,
+		InboundFee:                fn.Some(inboundFee),
 		ExtraOpaqueData:           extraOpaqueData,
 	}, nil
 }

routing/localchans/manager.go

@@ -127,12 +127,10 @@ func (r *Manager) UpdatePolicy(newSchema routing.ChannelPolicy,
 			Edge: edge,
 		})
 
-		// Extract inbound fees from the ExtraOpaqueData.
 		var inboundWireFee lnwire.Fee
-		_, err = edge.ExtraOpaqueData.ExtractRecords(&inboundWireFee)
-		if err != nil {
-			return err
-		}
+		edge.InboundFee.WhenSome(func(fee lnwire.Fee) {
+			inboundWireFee = fee
+		})
 		inboundFee := models.NewInboundFeeFromWire(inboundWireFee)
 
 		// Add updated policy to list of policies to send to switch.
@@ -372,6 +370,8 @@ func (r *Manager) updateEdge(chanPoint wire.OutPoint,
 	err = fn.MapOptionZ(newSchema.InboundFee,
 		func(f models.InboundFee) error {
 			inboundWireFee := f.ToWire()
+			edge.InboundFee = fn.Some(inboundWireFee)
+
 			return edge.ExtraOpaqueData.PackRecords(
 				&inboundWireFee,
 			)