refactor: move various duties from ChannelRouter to graph.Builder

This commit is a large refactor that moves over various responsibilities
from the ChannelRouter to the graph.Builder. These include all graph
related tasks such as:
- graph pruning
- validation of new network updates & persisting new updates
- notifying topology update clients of any changes.

This is a large commit but:
- many of the files are purely moved from `routing` to `graph`
- the business logic put in the graph Builder is copied exactly as is
  from the ChannelRouter with one exception:
- The ChannelRouter just needs to be able to call the Builder's
  `ApplyChannelUpdate` method. So this is now exported and provided to
the ChannelRouter as a config option.
- The trickiest part was just moving over the test code since quite a
  bit had to be duplicated.

autopilot/manager.go

@@ -6,9 +6,9 @@ import (
 
 	"github.com/btcsuite/btcd/btcec/v2"
 	"github.com/btcsuite/btcd/wire"
+	"github.com/lightningnetwork/lnd/graph"
 	"github.com/lightningnetwork/lnd/lnwallet"
 	"github.com/lightningnetwork/lnd/lnwire"
-	"github.com/lightningnetwork/lnd/routing"
 )
 
 // ManagerCfg houses a set of values and methods that is passed to the Manager
@@ -36,7 +36,7 @@ type ManagerCfg struct {
 
 	// SubscribeTopology is used to get a subscription for topology changes
 	// on the network.
-	SubscribeTopology func() (*routing.TopologyClient, error)
+	SubscribeTopology func() (*graph.TopologyClient, error)
 }
 
 // Manager is struct that manages an autopilot agent, making it possible to

discovery/chan_series.go

@@ -5,9 +5,9 @@ import (
 
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/lightningnetwork/lnd/channeldb"
+	"github.com/lightningnetwork/lnd/graph"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/netann"
-	"github.com/lightningnetwork/lnd/routing"
 	"github.com/lightningnetwork/lnd/routing/route"
 )
 
@@ -136,7 +136,7 @@ func (c *ChanSeries) UpdatesInHorizon(chain chainhash.Hash,
 		if edge1 != nil {
 			// We don't want to send channel updates that don't
 			// conform to the spec (anymore).
-			err := routing.ValidateChannelUpdateFields(0, edge1)
+			err := graph.ValidateChannelUpdateFields(0, edge1)
 			if err != nil {
 				log.Errorf("not sending invalid channel "+
 					"update %v: %v", edge1, err)
@@ -145,7 +145,7 @@ func (c *ChanSeries) UpdatesInHorizon(chain chainhash.Hash,
 			}
 		}
 		if edge2 != nil {
-			err := routing.ValidateChannelUpdateFields(0, edge2)
+			err := graph.ValidateChannelUpdateFields(0, edge2)
 			if err != nil {
 				log.Errorf("not sending invalid channel "+
 					"update %v: %v", edge2, err)

discovery/gossiper.go

@@ -29,7 +29,6 @@ import (
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/multimutex"
 	"github.com/lightningnetwork/lnd/netann"
-	"github.com/lightningnetwork/lnd/routing"
 	"github.com/lightningnetwork/lnd/routing/route"
 	"github.com/lightningnetwork/lnd/ticker"
 	"golang.org/x/time/rate"
@@ -1361,7 +1360,7 @@ func (d *AuthenticatedGossiper) networkHandler() {
 
 	// We'll use this validation to ensure that we process jobs in their
 	// dependency order during parallel validation.
-	validationBarrier := routing.NewValidationBarrier(1000, d.quit)
+	validationBarrier := graph.NewValidationBarrier(1000, d.quit)
 
 	for {
 		select {
@@ -1486,7 +1485,7 @@ func (d *AuthenticatedGossiper) networkHandler() {
 //
 // NOTE: must be run as a goroutine.
 func (d *AuthenticatedGossiper) handleNetworkMessages(nMsg *networkMsg,
-	deDuped *deDupedAnnouncements, vb *routing.ValidationBarrier) {
+	deDuped *deDupedAnnouncements, vb *graph.ValidationBarrier) {
 
 	defer d.wg.Done()
 	defer vb.CompleteJob()
@@ -1502,10 +1501,10 @@ func (d *AuthenticatedGossiper) handleNetworkMessages(nMsg *networkMsg,
 		log.Debugf("Validating network message %s got err: %v",
 			nMsg.msg.MsgType(), err)
 
-		if !routing.IsError(
+		if !graph.IsError(
 			err,
-			routing.ErrVBarrierShuttingDown,
-			routing.ErrParentValidationFailed,
+			graph.ErrVBarrierShuttingDown,
+			graph.ErrParentValidationFailed,
 		) {
 
 			log.Warnf("unexpected error during validation "+
@@ -1861,7 +1860,7 @@ func (d *AuthenticatedGossiper) processRejectedEdge(
 	if err != nil {
 		return nil, err
 	}
-	err = routing.ValidateChannelAnn(chanAnn)
+	err = graph.ValidateChannelAnn(chanAnn)
 	if err != nil {
 		err := fmt.Errorf("assembled channel announcement proof "+
 			"for shortChanID=%v isn't valid: %v",
@@ -1910,7 +1909,7 @@ func (d *AuthenticatedGossiper) processRejectedEdge(
 func (d *AuthenticatedGossiper) addNode(msg *lnwire.NodeAnnouncement,
 	op ...batch.SchedulerOption) error {
 
-	if err := routing.ValidateNodeAnn(msg); err != nil {
+	if err := graph.ValidateNodeAnn(msg); err != nil {
 		return fmt.Errorf("unable to validate node announcement: %w",
 			err)
 	}
@@ -2064,7 +2063,7 @@ func (d *AuthenticatedGossiper) processZombieUpdate(
 			"with chan_id=%v", msg.ShortChannelID)
 	}
 
-	err := routing.VerifyChannelUpdateSignature(msg, pubKey)
+	err := graph.VerifyChannelUpdateSignature(msg, pubKey)
 	if err != nil {
 		return fmt.Errorf("unable to verify channel "+
 			"update signature: %v", err)
@@ -2201,7 +2200,7 @@ func (d *AuthenticatedGossiper) updateChannel(info *models.ChannelEdgeInfo,
 
 	// To ensure that our signature is valid, we'll verify it ourself
 	// before committing it to the slice returned.
-	err = routing.ValidateChannelUpdateAnn(d.selfKey, info.Capacity, chanUpdate)
+	err = graph.ValidateChannelUpdateAnn(d.selfKey, info.Capacity, chanUpdate)
 	if err != nil {
 		return nil, nil, fmt.Errorf("generated invalid channel "+
 			"update sig: %v", err)
@@ -2338,11 +2337,11 @@ func (d *AuthenticatedGossiper) handleNodeAnnouncement(nMsg *networkMsg,
 		log.Debugf("Adding node: %x got error: %v", nodeAnn.NodeID,
 			err)
 
-		if !routing.IsError(
+		if !graph.IsError(
 			err,
-			routing.ErrOutdated,
-			routing.ErrIgnored,
-			routing.ErrVBarrierShuttingDown,
+			graph.ErrOutdated,
+			graph.ErrIgnored,
+			graph.ErrVBarrierShuttingDown,
 		) {
 
 			log.Error(err)
@@ -2457,7 +2456,7 @@ func (d *AuthenticatedGossiper) handleChanAnnouncement(nMsg *networkMsg,
 	// the signatures within the proof as it should be well formed.
 	var proof *models.ChannelAuthProof
 	if nMsg.isRemote {
-		if err := routing.ValidateChannelAnn(ann); err != nil {
+		if err := graph.ValidateChannelAnn(ann); err != nil {
 			err := fmt.Errorf("unable to validate announcement: "+
 				"%v", err)
 
@@ -2538,7 +2537,7 @@ func (d *AuthenticatedGossiper) handleChanAnnouncement(nMsg *networkMsg,
 		// If the edge was rejected due to already being known, then it
 		// may be the case that this new message has a fresh channel
 		// proof, so we'll check.
-		if routing.IsError(err, routing.ErrIgnored) {
+		if graph.IsError(err, graph.ErrIgnored) {
 			// Attempt to process the rejected message to see if we
 			// get any new announcements.
 			anns, rErr := d.processRejectedEdge(ann, proof)
@@ -2862,7 +2861,7 @@ func (d *AuthenticatedGossiper) handleChanUpdate(nMsg *networkMsg,
 	// Validate the channel announcement with the expected public key and
 	// channel capacity. In the case of an invalid channel update, we'll
 	// return an error to the caller and exit early.
-	err = routing.ValidateChannelUpdateAnn(pubKey, chanInfo.Capacity, upd)
+	err = graph.ValidateChannelUpdateAnn(pubKey, chanInfo.Capacity, upd)
 	if err != nil {
 		rErr := fmt.Errorf("unable to validate channel update "+
 			"announcement for short_chan_id=%v: %v",
@@ -2947,10 +2946,10 @@ func (d *AuthenticatedGossiper) handleChanUpdate(nMsg *networkMsg,
 	}
 
 	if err := d.cfg.Router.UpdateEdge(update, ops...); err != nil {
-		if routing.IsError(
-			err, routing.ErrOutdated,
-			routing.ErrIgnored,
-			routing.ErrVBarrierShuttingDown,
+		if graph.IsError(
+			err, graph.ErrOutdated,
+			graph.ErrIgnored,
+			graph.ErrVBarrierShuttingDown,
 		) {
 
 			log.Debugf("Update edge for short_chan_id(%v) got: %v",
@@ -3268,7 +3267,7 @@ func (d *AuthenticatedGossiper) handleAnnSig(nMsg *networkMsg,
 
 	// With all the necessary components assembled validate the full
 	// channel announcement proof.
-	if err := routing.ValidateChannelAnn(chanAnn); err != nil {
+	if err := graph.ValidateChannelAnn(chanAnn); err != nil {
 		err := fmt.Errorf("channel announcement proof for "+
 			"short_chan_id=%v isn't valid: %v", shortChanID, err)
 

discovery/gossiper_test.go

@@ -33,7 +33,6 @@ import (
 	"github.com/lightningnetwork/lnd/lntest/wait"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/netann"
-	"github.com/lightningnetwork/lnd/routing"
 	"github.com/lightningnetwork/lnd/routing/route"
 	"github.com/lightningnetwork/lnd/ticker"
 	"github.com/stretchr/testify/require"
@@ -351,7 +350,7 @@ func (r *mockGraphSource) IsStaleEdgePolicy(chanID lnwire.ShortChannelID,
 		// Since it exists within our zombie index, we'll check that it
 		// respects the router's live edge horizon to determine whether
 		// it is stale or not.
-		return time.Since(timestamp) > routing.DefaultChannelPruneExpiry
+		return time.Since(timestamp) > graph.DefaultChannelPruneExpiry
 	}
 
 	switch {
@@ -2258,7 +2257,7 @@ func TestProcessZombieEdgeNowLive(t *testing.T) {
 
 	// We'll generate a channel update with a timestamp far enough in the
 	// past to consider it a zombie.
-	zombieTimestamp := time.Now().Add(-routing.DefaultChannelPruneExpiry)
+	zombieTimestamp := time.Now().Add(-graph.DefaultChannelPruneExpiry)
 	batch.chanUpdAnn2.Timestamp = uint32(zombieTimestamp.Unix())
 	if err := signUpdate(remoteKeyPriv2, batch.chanUpdAnn2); err != nil {
 		t.Fatalf("unable to sign update with new timestamp: %v", err)

funding/manager.go

@@ -23,6 +23,7 @@ import (
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/channeldb/models"
 	"github.com/lightningnetwork/lnd/discovery"
+	"github.com/lightningnetwork/lnd/graph"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/labels"
@@ -33,7 +34,6 @@ import (
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
 	"github.com/lightningnetwork/lnd/lnwallet/chanfunding"
 	"github.com/lightningnetwork/lnd/lnwire"
-	"github.com/lightningnetwork/lnd/routing"
 	"golang.org/x/crypto/salsa20"
 )
 
@@ -3415,10 +3415,10 @@ func (f *Manager) addToRouterGraph(completeChan *channeldb.OpenChannel,
 	select {
 	case err := <-errChan:
 		if err != nil {
-			if routing.IsError(err, routing.ErrOutdated,
-				routing.ErrIgnored) {
+			if graph.IsError(err, graph.ErrOutdated,
+				graph.ErrIgnored) {
 
-				log.Debugf("Router rejected "+
+				log.Debugf("Graph rejected "+
 					"ChannelAnnouncement: %v", err)
 			} else {
 				return fmt.Errorf("error sending channel "+
@@ -3435,10 +3435,10 @@ func (f *Manager) addToRouterGraph(completeChan *channeldb.OpenChannel,
 	select {
 	case err := <-errChan:
 		if err != nil {
-			if routing.IsError(err, routing.ErrOutdated,
-				routing.ErrIgnored) {
+			if graph.IsError(err, graph.ErrOutdated,
+				graph.ErrIgnored) {
 
-				log.Debugf("Router rejected "+
+				log.Debugf("Graph rejected "+
 					"ChannelUpdate: %v", err)
 			} else {
 				return fmt.Errorf("error sending channel "+
@@ -4354,10 +4354,10 @@ func (f *Manager) announceChannel(localIDKey, remoteIDKey *btcec.PublicKey,
 	select {
 	case err := <-errChan:
 		if err != nil {
-			if routing.IsError(err, routing.ErrOutdated,
-				routing.ErrIgnored) {
+			if graph.IsError(err, graph.ErrOutdated,
+				graph.ErrIgnored) {
 
-				log.Debugf("Router rejected "+
+				log.Debugf("Graph rejected "+
 					"AnnounceSignatures: %v", err)
 			} else {
 				log.Errorf("Unable to send channel "+
@@ -4384,10 +4384,10 @@ func (f *Manager) announceChannel(localIDKey, remoteIDKey *btcec.PublicKey,
 	select {
 	case err := <-errChan:
 		if err != nil {
-			if routing.IsError(err, routing.ErrOutdated,
-				routing.ErrIgnored) {
+			if graph.IsError(err, graph.ErrOutdated,
+				graph.ErrIgnored) {
 
-				log.Debugf("Router rejected "+
+				log.Debugf("Graph rejected "+
 					"NodeAnnouncement: %v", err)
 			} else {
 				log.Errorf("Unable to send node "+

routing/ann_validation.go → graph/ann_validation.go

@@ -1,4 +1,4 @@
-package routing
+package graph
 
 import (
 	"bytes"