Merge pull request #1229 from wpaulino/randomize-link-fee-updates

htlcswitch: randomize link fee updates

htlcswitch/link.go

@@ -2,16 +2,15 @@ package htlcswitch
 
 import (
 	"bytes"
+	"crypto/sha256"
 	"fmt"
+	prand "math/rand"
 	"sync"
 	"sync/atomic"
 	"time"
 
-	"crypto/sha256"
-
 	"github.com/davecgh/go-spew/spew"
 	"github.com/go-errors/errors"
-	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/contractcourt"
 	"github.com/lightningnetwork/lnd/htlcswitch/hodl"
@@ -21,6 +20,10 @@ import (
 	"github.com/roasbeef/btcd/chaincfg/chainhash"
 )
 
+func init() {
+	prand.Seed(time.Now().UnixNano())
+}
+
 const (
 	// expiryGraceDelta is a grace period that the timeout of incoming
 	// HTLC's that pay directly to us (i.e we're the "exit node") must up
@@ -36,6 +39,12 @@ const (
 	// for a new fee update. We'll use this as a fee floor when proposing
 	// and accepting updates.
 	minCommitFeePerKw = 253
+
+	// DefaultMinLinkFeeUpdateTimeout and DefaultMaxLinkFeeUpdateTimeout
+	// represent the default timeout bounds in which a link should propose
+	// to update its commitment fee rate.
+	DefaultMinLinkFeeUpdateTimeout = 10 * time.Minute
+	DefaultMaxLinkFeeUpdateTimeout = 60 * time.Minute
 )
 
 // ForwardingPolicy describes the set of constraints that a given ChannelLink
@@ -202,13 +211,6 @@ type ChannelLinkConfig struct {
 	// transaction to ensure timely confirmation.
 	FeeEstimator lnwallet.FeeEstimator
 
-	// BlockEpochs is an active block epoch event stream backed by an
-	// active ChainNotifier instance. The ChannelLink will use new block
-	// notifications sent over this channel to decide when a _new_ HTLC is
-	// too close to expiry, and also when any active HTLC's have expired
-	// (or are close to expiry).
-	BlockEpochs *chainntnfs.BlockEpochEvent
-
 	// DebugHTLC should be turned on if you want all HTLCs sent to a node
 	// with the debug htlc R-Hash are immediately settled in the next
 	// available state transition.
@@ -248,6 +250,12 @@ type ChannelLinkConfig struct {
 	// in testing, it is here to ensure the sphinx replay detection on the
 	// receiving node is persistent.
 	UnsafeReplay bool
+
+	// MinFeeUpdateTimeout and MaxFeeUpdateTimeout represent the timeout
+	// interval bounds in which a link will propose to update its commitment
+	// fee rate. A random timeout will be selected between these values.
+	MinFeeUpdateTimeout time.Duration
+	MaxFeeUpdateTimeout time.Duration
 }
 
 // channelLink is the service which drives a channel's commitment update
@@ -273,10 +281,6 @@ type channelLink struct {
 	// method in state machine.
 	batchCounter uint32
 
-	// bestHeight is the best known height of the main chain. The link will
-	// use this information to govern decisions based on HTLC timeouts.
-	bestHeight uint32
-
 	// keystoneBatch represents a volatile list of keystones that must be
 	// written before attempting to sign the next commitment txn. These
 	// represent all the HTLC's forwarded to the link from the switch. Once
@@ -342,6 +346,10 @@ type channelLink struct {
 	logCommitTimer *time.Timer
 	logCommitTick  <-chan time.Time
 
+	// updateFeeTimer is the timer responsible for updating the link's
+	// commitment fee every time it fires.
+	updateFeeTimer *time.Timer
+
 	sync.RWMutex
 
 	wg   sync.WaitGroup
@@ -350,8 +358,8 @@ type channelLink struct {
 
 // NewChannelLink creates a new instance of a ChannelLink given a configuration
 // and active channel that will be used to verify/apply updates to.
-func NewChannelLink(cfg ChannelLinkConfig, channel *lnwallet.LightningChannel,
+func NewChannelLink(cfg ChannelLinkConfig,
-	currentHeight uint32) ChannelLink {
+	channel *lnwallet.LightningChannel) ChannelLink {
 
 	return &channelLink{
 		cfg:         cfg,
@@ -360,7 +368,6 @@ func NewChannelLink(cfg ChannelLinkConfig, channel *lnwallet.LightningChannel,
 		// TODO(roasbeef): just do reserve here?
 		logCommitTimer: time.NewTimer(300 * time.Millisecond),
 		overflowQueue:  newPacketQueue(lnwallet.MaxHTLCNumber / 2),
-		bestHeight:     currentHeight,
 		htlcUpdates:    make(chan []channeldb.HTLC),
 		quit:           make(chan struct{}),
 	}
@@ -427,6 +434,8 @@ func (l *channelLink) Start() error {
 		}
 	}
 
+	l.updateFeeTimer = time.NewTimer(l.randomFeeUpdateTimeout())
+
 	l.wg.Add(1)
 	go l.htlcManager()
 
@@ -449,8 +458,8 @@ func (l *channelLink) Stop() {
 		l.cfg.ChainEvents.Cancel()
 	}
 
+	l.updateFeeTimer.Stop()
 	l.channel.Stop()
-
 	l.overflowQueue.Stop()
 
 	close(l.quit)
@@ -781,7 +790,6 @@ func (l *channelLink) fwdPkgGarbager() {
 func (l *channelLink) htlcManager() {
 	defer func() {
 		l.wg.Done()
-		l.cfg.BlockEpochs.Cancel()
 		log.Infof("ChannelLink(%v) has exited", l)
 	}()
 
@@ -835,7 +843,6 @@ func (l *channelLink) htlcManager() {
 
 out:
 	for {
-
 		// We must always check if we failed at some point processing
 		// the last update before processing the next.
 		if l.failed {
@@ -844,16 +851,10 @@ out:
 		}
 
 		select {
-
+		// Our update fee timer has fired, so we'll check the network
-		// A new block has arrived, we'll check the network fee to see
+		// fee to see if we should adjust our commitment fee.
-		// if we should adjust our commitment fee, and also update our
+		case <-l.updateFeeTimer.C:
-		// track of the best current height.
+			l.updateFeeTimer.Reset(l.randomFeeUpdateTimeout())
-		case blockEpoch, ok := <-l.cfg.BlockEpochs.Epochs:
-			if !ok {
-				break out
-			}
-
-			l.bestHeight = uint32(blockEpoch.Height)
 
 			// If we're not the initiator of the channel, don't we
 			// don't control the fees, so we can ignore this.
@@ -983,6 +984,20 @@ out:
 	}
 }
 
+// randomFeeUpdateTimeout returns a random timeout between the bounds defined
+// within the link's configuration that will be used to determine when the link
+// should propose an update to its commitment fee rate.
+func (l *channelLink) randomFeeUpdateTimeout() time.Duration {
+	lower := int64(l.cfg.MinFeeUpdateTimeout)
+	upper := int64(l.cfg.MaxFeeUpdateTimeout)
+	rand := prand.Int63n(upper)
+	if rand < lower {
+		rand = lower
+	}
+
+	return time.Duration(rand)
+}
+
 // handleDownStreamPkt processes an HTLC packet sent from the downstream HTLC
 // Switch. Possible messages sent by the switch include requests to forward new
 // HTLCs, timeout previously cleared HTLCs, and finally to settle currently
@@ -2065,7 +2080,7 @@ func (l *channelLink) processRemoteAdds(fwdPkg *channeldb.FwdPkg,
 			continue
 		}
 
-		heightNow := l.bestHeight
+		heightNow := l.cfg.Switch.BestHeight()
 
 		fwdInfo := chanIterator.ForwardingInstructions()
 		switch fwdInfo.NextHop {

htlcswitch/link_test.go

@@ -6,6 +6,7 @@ import (
 	"encoding/binary"
 	"fmt"
 	"io"
+	"math"
 	"reflect"
 	"runtime"
 	"strings"
@@ -13,12 +14,9 @@ import (
 	"testing"
 	"time"
 
-	"math"
-
 	"github.com/coreos/bbolt"
 	"github.com/davecgh/go-spew/spew"
 	"github.com/go-errors/errors"
-	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/contractcourt"
 	"github.com/lightningnetwork/lnd/htlcswitch/hodl"
@@ -1057,7 +1055,7 @@ func TestChannelLinkMultiHopUnknownNextHop(t *testing.T) {
 	htlcAmt, totalTimelock, hops := generateHops(amount, testStartingHeight,
 		n.firstBobChannelLink, n.carolChannelLink)
 
-	daveServer, err := newMockServer(t, "dave", nil)
+	daveServer, err := newMockServer(t, "dave", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to init dave's server: %v", err)
 	}
@@ -1443,11 +1441,6 @@ func newSingleLinkTestHarness(chanAmt, chanReserve btcutil.Amount) (
 	}
 
 	var (
-		globalEpoch = &chainntnfs.BlockEpochEvent{
-			Epochs: make(chan *chainntnfs.BlockEpoch),
-			Cancel: func() {
-			},
-		}
 		invoiceRegistry = newMockRegistry()
 		decoder         = newMockIteratorDecoder()
 		obfuscator      = NewMockObfuscator()
@@ -1468,7 +1461,7 @@ func newSingleLinkTestHarness(chanAmt, chanReserve btcutil.Amount) (
 	}
 
 	aliceDb := aliceChannel.State().Db
-	aliceSwitch, err := initSwitchWithDB(aliceDb)
+	aliceSwitch, err := initSwitchWithDB(testStartingHeight, aliceDb)
 	if err != nil {
 		return nil, nil, nil, nil, nil, nil, err
 	}
@@ -1495,16 +1488,17 @@ func newSingleLinkTestHarness(chanAmt, chanReserve btcutil.Amount) (
 		},
 		Registry:       invoiceRegistry,
 		ChainEvents:    &contractcourt.ChainEventSubscription{},
-		BlockEpochs:    globalEpoch,
 		BatchTicker:    ticker,
 		FwdPkgGCTicker: NewBatchTicker(time.NewTicker(5 * time.Second)),
-		// Make the BatchSize large enough to not
+		// Make the BatchSize and Min/MaxFeeUpdateTimeout large enough
-		// trigger commit update automatically during tests.
+		// to not trigger commit updates automatically during tests.
 		BatchSize:           10000,
+		MinFeeUpdateTimeout: 30 * time.Minute,
+		MaxFeeUpdateTimeout: 30 * time.Minute,
 	}
 
 	const startingHeight = 100
-	aliceLink := NewChannelLink(aliceCfg, aliceChannel, startingHeight)
+	aliceLink := NewChannelLink(aliceCfg, aliceChannel)
 	start := func() error {
 		return aliceSwitch.AddLink(aliceLink)
 	}
@@ -3451,22 +3445,9 @@ func TestChannelLinkUpdateCommitFee(t *testing.T) {
 	defer n.stop()
 	defer n.feeEstimator.Stop()
 
-	// First, we'll start off all channels at "height" 9000 by sending a
+	// For the sake of this test, we'll reset the timer to fire in a second
-	// new epoch to all the clients.
+	// so that Alice's link queries for a new network fee.
-	select {
+	n.aliceChannelLink.updateFeeTimer.Reset(time.Millisecond)
-	case n.aliceBlockEpoch <- &chainntnfs.BlockEpoch{
-		Height: 9000,
-	}:
-	case <-time.After(time.Second * 5):
-		t.Fatalf("link didn't read block epoch")
-	}
-	select {
-	case n.bobFirstBlockEpoch <- &chainntnfs.BlockEpoch{
-		Height: 9000,
-	}:
-	case <-time.After(time.Second * 5):
-		t.Fatalf("link didn't read block epoch")
-	}
 
 	startingFeeRate := channels.aliceToBob.CommitFeeRate()
 
@@ -3480,20 +3461,15 @@ func TestChannelLinkUpdateCommitFee(t *testing.T) {
 	select {
 	case n.feeEstimator.byteFeeIn <- startingFeeRateSatPerVByte:
 	case <-time.After(time.Second * 5):
-		t.Fatalf("alice didn't query for the new " +
+		t.Fatalf("alice didn't query for the new network fee")
-			"network fee")
 	}
 
-	time.Sleep(time.Millisecond * 500)
+	time.Sleep(time.Second)
 
 	// The fee rate on the alice <-> bob channel should still be the same
 	// on both sides.
 	aliceFeeRate := channels.aliceToBob.CommitFeeRate()
 	bobFeeRate := channels.bobToAlice.CommitFeeRate()
-	if aliceFeeRate != bobFeeRate {
-		t.Fatalf("fee rates don't match: expected %v got %v",
-			aliceFeeRate, bobFeeRate)
-	}
 	if aliceFeeRate != startingFeeRate {
 		t.Fatalf("alice's fee rate shouldn't have changed: "+
 			"expected %v, got %v", aliceFeeRate, startingFeeRate)
@@ -3503,22 +3479,9 @@ func TestChannelLinkUpdateCommitFee(t *testing.T) {
 			"expected %v, got %v", bobFeeRate, startingFeeRate)
 	}
 
-	// Now we'll send a new block update to all end points, with a new
+	// We'll reset the timer once again to ensure Alice's link queries for a
-	// height THAT'S OVER 9000!!!
+	// new network fee.
-	select {
+	n.aliceChannelLink.updateFeeTimer.Reset(time.Millisecond)
-	case n.aliceBlockEpoch <- &chainntnfs.BlockEpoch{
-		Height: 9001,
-	}:
-	case <-time.After(time.Second * 5):
-		t.Fatalf("link didn't read block epoch")
-	}
-	select {
-	case n.bobFirstBlockEpoch <- &chainntnfs.BlockEpoch{
-		Height: 9001,
-	}:
-	case <-time.After(time.Second * 5):
-		t.Fatalf("link didn't read block epoch")
-	}
 
 	// Next, we'll set up a deliver a fee rate that's triple the current
 	// fee rate. This should cause the Alice (the initiator) to trigger a
@@ -3527,11 +3490,10 @@ func TestChannelLinkUpdateCommitFee(t *testing.T) {
 	select {
 	case n.feeEstimator.byteFeeIn <- startingFeeRateSatPerVByte * 3:
 	case <-time.After(time.Second * 5):
-		t.Fatalf("alice didn't query for the new " +
+		t.Fatalf("alice didn't query for the new network fee")
-			"network fee")
 	}
 
-	time.Sleep(time.Second * 2)
+	time.Sleep(time.Second)
 
 	// At this point, Alice should've triggered a new fee update that
 	// increased the fee rate to match the new rate.
@@ -3545,10 +3507,6 @@ func TestChannelLinkUpdateCommitFee(t *testing.T) {
 		t.Fatalf("bob's fee rate didn't change: expected %v, got %v",
 			newFeeRate, aliceFeeRate)
 	}
-	if aliceFeeRate != bobFeeRate {
-		t.Fatalf("fee rates don't match: expected %v got %v",
-			aliceFeeRate, bobFeeRate)
-	}
 }
 
 // TestChannelLinkAcceptDuplicatePayment tests that if a link receives an
@@ -3859,11 +3817,6 @@ func restartLink(aliceChannel *lnwallet.LightningChannel, aliceSwitch *Switch,
 	hodlFlags []hodl.Flag) (ChannelLink, chan time.Time, func(), error) {
 
 	var (
-		globalEpoch = &chainntnfs.BlockEpochEvent{
-			Epochs: make(chan *chainntnfs.BlockEpoch),
-			Cancel: func() {
-			},
-		}
 		invoiceRegistry = newMockRegistry()
 		decoder         = newMockIteratorDecoder()
 		obfuscator      = NewMockObfuscator()
@@ -3888,7 +3841,7 @@ func restartLink(aliceChannel *lnwallet.LightningChannel, aliceSwitch *Switch,
 
 	if aliceSwitch == nil {
 		var err error
-		aliceSwitch, err = initSwitchWithDB(aliceDb)
+		aliceSwitch, err = initSwitchWithDB(testStartingHeight, aliceDb)
 		if err != nil {
 			return nil, nil, nil, err
 		}
@@ -3914,19 +3867,20 @@ func restartLink(aliceChannel *lnwallet.LightningChannel, aliceSwitch *Switch,
 		},
 		Registry:       invoiceRegistry,
 		ChainEvents:    &contractcourt.ChainEventSubscription{},
-		BlockEpochs:    globalEpoch,
 		BatchTicker:    ticker,
 		FwdPkgGCTicker: NewBatchTicker(time.NewTicker(5 * time.Second)),
-		// Make the BatchSize large enough to not
+		// Make the BatchSize and Min/MaxFeeUpdateTimeout large enough
-		// trigger commit update automatically during tests.
+		// to not trigger commit updates automatically during tests.
 		BatchSize:           10000,
+		MinFeeUpdateTimeout: 30 * time.Minute,
+		MaxFeeUpdateTimeout: 30 * time.Minute,
 		// Set any hodl flags requested for the new link.
 		HodlMask:  hodl.MaskFromFlags(hodlFlags...),
 		DebugHTLC: len(hodlFlags) > 0,
 	}
 
 	const startingHeight = 100
-	aliceLink := NewChannelLink(aliceCfg, aliceChannel, startingHeight)
+	aliceLink := NewChannelLink(aliceCfg, aliceChannel)
 	if err := aliceSwitch.AddLink(aliceLink); err != nil {
 		return nil, nil, nil, err
 	}

htlcswitch/mock.go

@@ -1,19 +1,17 @@
 package htlcswitch
 
 import (
+	"bytes"
 	"crypto/sha256"
 	"encoding/binary"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 
-	"io"
-	"sync/atomic"
-
-	"bytes"
-
 	"github.com/btcsuite/fastsha256"
 	"github.com/go-errors/errors"
 	"github.com/lightningnetwork/lightning-onion"
@@ -122,7 +120,7 @@ type mockServer struct {
 
 var _ lnpeer.Peer = (*mockServer)(nil)
 
-func initSwitchWithDB(db *channeldb.DB) (*Switch, error) {
+func initSwitchWithDB(startingHeight uint32, db *channeldb.DB) (*Switch, error) {
 	if db == nil {
 		tempPath, err := ioutil.TempDir("", "switchdb")
 		if err != nil {
@@ -135,7 +133,7 @@ func initSwitchWithDB(db *channeldb.DB) (*Switch, error) {
 		}
 	}
 
-	return New(Config{
+	cfg := Config{
 		DB:             db,
 		SwitchPackager: channeldb.NewSwitchPackager(),
 		FwdingLog: &mockForwardingLog{
@@ -144,15 +142,20 @@ func initSwitchWithDB(db *channeldb.DB) (*Switch, error) {
 		FetchLastChannelUpdate: func(lnwire.ShortChannelID) (*lnwire.ChannelUpdate, error) {
 			return nil, nil
 		},
-	})
+		Notifier: &mockNotifier{},
+	}
+
+	return New(cfg, startingHeight)
 }
 
-func newMockServer(t testing.TB, name string, db *channeldb.DB) (*mockServer, error) {
+func newMockServer(t testing.TB, name string, startingHeight uint32,
+	db *channeldb.DB) (*mockServer, error) {
+
 	var id [33]byte
 	h := sha256.Sum256([]byte(name))
 	copy(id[:], h[:])
 
-	htlcSwitch, err := initSwitchWithDB(db)
+	htlcSwitch, err := initSwitchWithDB(startingHeight, db)
 	if err != nil {
 		return nil, err
 	}

htlcswitch/switch.go

@@ -2,23 +2,22 @@ package htlcswitch
 
 import (
 	"bytes"
+	"crypto/sha256"
 	"fmt"
 	"sync"
 	"sync/atomic"
 	"time"
 
-	"crypto/sha256"
-
 	"github.com/coreos/bbolt"
 	"github.com/davecgh/go-spew/spew"
-	"github.com/roasbeef/btcd/btcec"
-
 	"github.com/go-errors/errors"
+	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/contractcourt"
 	"github.com/lightningnetwork/lnd/lnrpc"
 	"github.com/lightningnetwork/lnd/lnwallet"
 	"github.com/lightningnetwork/lnd/lnwire"
+	"github.com/roasbeef/btcd/btcec"
 	"github.com/roasbeef/btcd/wire"
 	"github.com/roasbeef/btcutil"
 )
@@ -142,6 +141,10 @@ type Config struct {
 	// provide payment senders our latest policy when sending encrypted
 	// error messages.
 	FetchLastChannelUpdate func(lnwire.ShortChannelID) (*lnwire.ChannelUpdate, error)
+
+	// Notifier is an instance of a chain notifier that we'll use to signal
+	// the switch when a new block has arrived.
+	Notifier chainntnfs.ChainNotifier
 }
 
 // Switch is the central messaging bus for all incoming/outgoing HTLCs.
@@ -155,6 +158,12 @@ type Config struct {
 type Switch struct {
 	started  int32 // To be used atomically.
 	shutdown int32 // To be used atomically.
+
+	// bestHeight is the best known height of the main chain. The links will
+	// be used this information to govern decisions based on HTLC timeouts.
+	// This will be retrieved by the registered links atomically.
+	bestHeight uint32
+
 	wg   sync.WaitGroup
 	quit chan struct{}
 
@@ -229,10 +238,15 @@ type Switch struct {
 	// to the forwarding log.
 	fwdEventMtx         sync.Mutex
 	pendingFwdingEvents []channeldb.ForwardingEvent
+
+	// blockEpochStream is an active block epoch event stream backed by an
+	// active ChainNotifier instance. This will be used to retrieve the
+	// lastest height of the chain.
+	blockEpochStream *chainntnfs.BlockEpochEvent
 }
 
 // New creates the new instance of htlc switch.
-func New(cfg Config) (*Switch, error) {
+func New(cfg Config, currentHeight uint32) (*Switch, error) {
 	circuitMap, err := NewCircuitMap(&CircuitMapConfig{
 		DB: cfg.DB,
 		ExtractErrorEncrypter: cfg.ExtractErrorEncrypter,
@@ -247,6 +261,7 @@ func New(cfg Config) (*Switch, error) {
 	}
 
 	return &Switch{
+		bestHeight:        currentHeight,
 		cfg:               &cfg,
 		circuits:          circuitMap,
 		paymentSequencer:  sequencer,
@@ -1339,8 +1354,10 @@ func (s *Switch) CloseLink(chanPoint *wire.OutPoint, closeType ChannelCloseType,
 func (s *Switch) htlcForwarder() {
 	defer s.wg.Done()
 
-	// Remove all links once we've been signalled for shutdown.
 	defer func() {
+		s.blockEpochStream.Cancel()
+
+		// Remove all links once we've been signalled for shutdown.
 		s.indexMtx.Lock()
 		for _, link := range s.linkIndex {
 			if err := s.removeLink(link.ChanID()); err != nil {
@@ -1378,8 +1395,15 @@ func (s *Switch) htlcForwarder() {
 	fwdEventTicker := time.NewTicker(15 * time.Second)
 	defer fwdEventTicker.Stop()
 
+out:
 	for {
 		select {
+		case blockEpoch, ok := <-s.blockEpochStream.Epochs:
+			if !ok {
+				break out
+			}
+
+			atomic.StoreUint32(&s.bestHeight, uint32(blockEpoch.Height))
 		// A local close request has arrived, we'll forward this to the
 		// relevant link (if it exists) so the channel can be
 		// cooperatively closed (if possible).
@@ -1549,6 +1573,12 @@ func (s *Switch) Start() error {
 
 	log.Infof("Starting HTLC Switch")
 
+	blockEpochStream, err := s.cfg.Notifier.RegisterBlockEpochNtfn()
+	if err != nil {
+		return err
+	}
+	s.blockEpochStream = blockEpochStream
+
 	s.wg.Add(1)
 	go s.htlcForwarder()
 
@@ -2033,3 +2063,8 @@ func (s *Switch) FlushForwardingEvents() error {
 	// forwarding log.
 	return s.cfg.FwdingLog.AddForwardingEvents(events)
 }
+
+// BestHeight returns the best height known to the switch.
+func (s *Switch) BestHeight() uint32 {
+	return atomic.LoadUint32(&s.bestHeight)
+}

htlcswitch/switch_test.go

@@ -30,12 +30,12 @@ func genPreimage() ([32]byte, error) {
 func TestSwitchSendPending(t *testing.T) {
 	t.Parallel()
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
 
-	s, err := initSwitchWithDB(nil)
+	s, err := initSwitchWithDB(testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -125,16 +125,16 @@ func TestSwitchSendPending(t *testing.T) {
 func TestSwitchForward(t *testing.T) {
 	t.Parallel()
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
-	bobPeer, err := newMockServer(t, "bob", nil)
+	bobPeer, err := newMockServer(t, "bob", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create bob server: %v", err)
 	}
 
-	s, err := initSwitchWithDB(nil)
+	s, err := initSwitchWithDB(testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -230,11 +230,11 @@ func TestSwitchForwardFailAfterFullAdd(t *testing.T) {
 
 	chanID1, chanID2, aliceChanID, bobChanID := genIDs()
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
-	bobPeer, err := newMockServer(t, "bob", nil)
+	bobPeer, err := newMockServer(t, "bob", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create bob server: %v", err)
 	}
@@ -249,7 +249,7 @@ func TestSwitchForwardFailAfterFullAdd(t *testing.T) {
 		t.Fatalf("unable to open channeldb: %v", err)
 	}
 
-	s, err := initSwitchWithDB(cdb)
+	s, err := initSwitchWithDB(testStartingHeight, cdb)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -344,7 +344,7 @@ func TestSwitchForwardFailAfterFullAdd(t *testing.T) {
 		t.Fatalf("unable to reopen channeldb: %v", err)
 	}
 
-	s2, err := initSwitchWithDB(cdb2)
+	s2, err := initSwitchWithDB(testStartingHeight, cdb2)
 	if err != nil {
 		t.Fatalf("unable reinit switch: %v", err)
 	}
@@ -421,11 +421,11 @@ func TestSwitchForwardSettleAfterFullAdd(t *testing.T) {
 
 	chanID1, chanID2, aliceChanID, bobChanID := genIDs()
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
-	bobPeer, err := newMockServer(t, "bob", nil)
+	bobPeer, err := newMockServer(t, "bob", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create bob server: %v", err)
 	}
@@ -440,7 +440,7 @@ func TestSwitchForwardSettleAfterFullAdd(t *testing.T) {
 		t.Fatalf("unable to open channeldb: %v", err)
 	}
 
-	s, err := initSwitchWithDB(cdb)
+	s, err := initSwitchWithDB(testStartingHeight, cdb)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -535,7 +535,7 @@ func TestSwitchForwardSettleAfterFullAdd(t *testing.T) {
 		t.Fatalf("unable to reopen channeldb: %v", err)
 	}
 
-	s2, err := initSwitchWithDB(cdb2)
+	s2, err := initSwitchWithDB(testStartingHeight, cdb2)
 	if err != nil {
 		t.Fatalf("unable reinit switch: %v", err)
 	}
@@ -615,11 +615,11 @@ func TestSwitchForwardDropAfterFullAdd(t *testing.T) {
 
 	chanID1, chanID2, aliceChanID, bobChanID := genIDs()
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
-	bobPeer, err := newMockServer(t, "bob", nil)
+	bobPeer, err := newMockServer(t, "bob", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create bob server: %v", err)
 	}
@@ -634,7 +634,7 @@ func TestSwitchForwardDropAfterFullAdd(t *testing.T) {
 		t.Fatalf("unable to open channeldb: %v", err)
 	}
 
-	s, err := initSwitchWithDB(cdb)
+	s, err := initSwitchWithDB(testStartingHeight, cdb)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -721,7 +721,7 @@ func TestSwitchForwardDropAfterFullAdd(t *testing.T) {
 		t.Fatalf("unable to reopen channeldb: %v", err)
 	}
 
-	s2, err := initSwitchWithDB(cdb2)
+	s2, err := initSwitchWithDB(testStartingHeight, cdb2)
 	if err != nil {
 		t.Fatalf("unable reinit switch: %v", err)
 	}
@@ -778,11 +778,11 @@ func TestSwitchForwardFailAfterHalfAdd(t *testing.T) {
 
 	chanID1, chanID2, aliceChanID, bobChanID := genIDs()
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
-	bobPeer, err := newMockServer(t, "bob", nil)
+	bobPeer, err := newMockServer(t, "bob", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create bob server: %v", err)
 	}
@@ -797,7 +797,7 @@ func TestSwitchForwardFailAfterHalfAdd(t *testing.T) {
 		t.Fatalf("unable to open channeldb: %v", err)
 	}
 
-	s, err := initSwitchWithDB(cdb)
+	s, err := initSwitchWithDB(testStartingHeight, cdb)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -879,7 +879,7 @@ func TestSwitchForwardFailAfterHalfAdd(t *testing.T) {
 		t.Fatalf("unable to reopen channeldb: %v", err)
 	}
 
-	s2, err := initSwitchWithDB(cdb2)
+	s2, err := initSwitchWithDB(testStartingHeight, cdb2)
 	if err != nil {
 		t.Fatalf("unable reinit switch: %v", err)
 	}
@@ -936,11 +936,11 @@ func TestSwitchForwardCircuitPersistence(t *testing.T) {
 
 	chanID1, chanID2, aliceChanID, bobChanID := genIDs()
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
-	bobPeer, err := newMockServer(t, "bob", nil)
+	bobPeer, err := newMockServer(t, "bob", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create bob server: %v", err)
 	}
@@ -955,7 +955,7 @@ func TestSwitchForwardCircuitPersistence(t *testing.T) {
 		t.Fatalf("unable to open channeldb: %v", err)
 	}
 
-	s, err := initSwitchWithDB(cdb)
+	s, err := initSwitchWithDB(testStartingHeight, cdb)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -1036,7 +1036,7 @@ func TestSwitchForwardCircuitPersistence(t *testing.T) {
 		t.Fatalf("unable to reopen channeldb: %v", err)
 	}
 
-	s2, err := initSwitchWithDB(cdb2)
+	s2, err := initSwitchWithDB(testStartingHeight, cdb2)
 	if err != nil {
 		t.Fatalf("unable reinit switch: %v", err)
 	}
@@ -1129,7 +1129,7 @@ func TestSwitchForwardCircuitPersistence(t *testing.T) {
 		t.Fatalf("unable to reopen channeldb: %v", err)
 	}
 
-	s3, err := initSwitchWithDB(cdb3)
+	s3, err := initSwitchWithDB(testStartingHeight, cdb3)
 	if err != nil {
 		t.Fatalf("unable reinit switch: %v", err)
 	}
@@ -1167,16 +1167,16 @@ func TestSkipIneligibleLinksMultiHopForward(t *testing.T) {
 
 	var packet *htlcPacket
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
-	bobPeer, err := newMockServer(t, "bob", nil)
+	bobPeer, err := newMockServer(t, "bob", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create bob server: %v", err)
 	}
 
-	s, err := initSwitchWithDB(nil)
+	s, err := initSwitchWithDB(testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -1237,12 +1237,12 @@ func TestSkipIneligibleLinksLocalForward(t *testing.T) {
 
 	// We'll create a single link for this test, marking it as being unable
 	// to forward form the get go.
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
 
-	s, err := initSwitchWithDB(nil)
+	s, err := initSwitchWithDB(testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -1289,16 +1289,16 @@ func TestSkipIneligibleLinksLocalForward(t *testing.T) {
 func TestSwitchCancel(t *testing.T) {
 	t.Parallel()
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
-	bobPeer, err := newMockServer(t, "bob", nil)
+	bobPeer, err := newMockServer(t, "bob", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create bob server: %v", err)
 	}
 
-	s, err := initSwitchWithDB(nil)
+	s, err := initSwitchWithDB(testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -1402,16 +1402,16 @@ func TestSwitchAddSamePayment(t *testing.T) {
 
 	chanID1, chanID2, aliceChanID, bobChanID := genIDs()
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
-	bobPeer, err := newMockServer(t, "bob", nil)
+	bobPeer, err := newMockServer(t, "bob", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create bob server: %v", err)
 	}
 
-	s, err := initSwitchWithDB(nil)
+	s, err := initSwitchWithDB(testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -1561,12 +1561,12 @@ func TestSwitchAddSamePayment(t *testing.T) {
 func TestSwitchSendPayment(t *testing.T) {
 	t.Parallel()
 
-	alicePeer, err := newMockServer(t, "alice", nil)
+	alicePeer, err := newMockServer(t, "alice", testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
 
-	s, err := initSwitchWithDB(nil)
+	s, err := initSwitchWithDB(testStartingHeight, nil)
 	if err != nil {
 		t.Fatalf("unable to init switch: %v", err)
 	}
@@ -1805,8 +1805,6 @@ func TestMultiHopPaymentForwardingEvents(t *testing.T) {
 		}
 	}
 
-	time.Sleep(time.Millisecond * 200)
-
 	// With all 10 payments sent. We'll now manually stop each of the
 	// switches so we can examine their end state.
 	n.stop()

htlcswitch/test_utils.go

@@ -17,7 +17,6 @@ import (
 	"github.com/btcsuite/fastsha256"
 	"github.com/coreos/bbolt"
 	"github.com/go-errors/errors"
-	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/contractcourt"
 	"github.com/lightningnetwork/lnd/keychain"
@@ -569,22 +568,13 @@ func generateRoute(hops ...ForwardingInfo) ([lnwire.OnionPacketSize]byte, error)
 type threeHopNetwork struct {
 	aliceServer      *mockServer
 	aliceChannelLink *channelLink
-	aliceBlockEpoch  chan *chainntnfs.BlockEpoch
-	aliceTicker      *time.Ticker
-
-	firstBobChannelLink *channelLink
-	bobFirstBlockEpoch  chan *chainntnfs.BlockEpoch
-	firstBobTicker      *time.Ticker
 
 	bobServer            *mockServer
+	firstBobChannelLink  *channelLink
 	secondBobChannelLink *channelLink
-	bobSecondBlockEpoch  chan *chainntnfs.BlockEpoch
-	secondBobTicker      *time.Ticker
 
-	carolChannelLink *channelLink
 	carolServer      *mockServer
-	carolBlockEpoch  chan *chainntnfs.BlockEpoch
+	carolChannelLink *channelLink
-	carolTicker      *time.Ticker
 
 	feeEstimator *mockFeeEstimator
 
@@ -762,11 +752,6 @@ func (n *threeHopNetwork) stop() {
 		done <- struct{}{}
 	}()
 
-	n.aliceTicker.Stop()
-	n.firstBobTicker.Stop()
-	n.secondBobTicker.Stop()
-	n.carolTicker.Stop()
-
 	for i := 0; i < 3; i++ {
 		<-done
 	}
@@ -858,15 +843,15 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 	carolDb := carolChannel.State().Db
 
 	// Create three peers/servers.
-	aliceServer, err := newMockServer(t, "alice", aliceDb)
+	aliceServer, err := newMockServer(t, "alice", startingHeight, aliceDb)
 	if err != nil {
 		t.Fatalf("unable to create alice server: %v", err)
 	}
-	bobServer, err := newMockServer(t, "bob", bobDb)
+	bobServer, err := newMockServer(t, "bob", startingHeight, bobDb)
 	if err != nil {
 		t.Fatalf("unable to create bob server: %v", err)
 	}
-	carolServer, err := newMockServer(t, "carol", carolDb)
+	carolServer, err := newMockServer(t, "carol", startingHeight, carolDb)
 	if err != nil {
 		t.Fatalf("unable to create carol server: %v", err)
 	}
@@ -882,6 +867,12 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 		quit:      make(chan struct{}),
 	}
 
+	const (
+		batchTimeout     = 50 * time.Millisecond
+		fwdPkgTimeout    = 5 * time.Second
+		feeUpdateTimeout = 30 * time.Minute
+	)
+
 	pCache := &mockPreimageCache{
 		// hash -> preimage
 		preimageMap: make(map[[32]byte][]byte),
@@ -894,13 +885,6 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 	}
 	obfuscator := NewMockObfuscator()
 
-	aliceEpochChan := make(chan *chainntnfs.BlockEpoch)
-	aliceEpoch := &chainntnfs.BlockEpochEvent{
-		Epochs: aliceEpochChan,
-		Cancel: func() {
-		},
-	}
-	aliceTicker := time.NewTicker(50 * time.Millisecond)
 	aliceChannelLink := NewChannelLink(
 		ChannelLinkConfig{
 			Switch:             aliceServer.htlcSwitch,
@@ -915,7 +899,6 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 			},
 			FetchLastChannelUpdate: mockGetChanUpdateMessage,
 			Registry:               aliceServer.registry,
-			BlockEpochs:            aliceEpoch,
 			FeeEstimator:           feeEstimator,
 			PreimageCache:          pCache,
 			UpdateContractSignals: func(*contractcourt.ContractSignals) error {
@@ -923,12 +906,14 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 			},
 			ChainEvents:         &contractcourt.ChainEventSubscription{},
 			SyncStates:          true,
-			BatchTicker:    &mockTicker{aliceTicker.C},
-			FwdPkgGCTicker: &mockTicker{time.NewTicker(5 * time.Second).C},
 			BatchSize:           10,
+			BatchTicker:         &mockTicker{time.NewTicker(batchTimeout).C},
+			FwdPkgGCTicker:      &mockTicker{time.NewTicker(fwdPkgTimeout).C},
+			MinFeeUpdateTimeout: feeUpdateTimeout,
+			MaxFeeUpdateTimeout: feeUpdateTimeout,
+			OnChannelFailure:    func(lnwire.ChannelID, lnwire.ShortChannelID, LinkFailureError) {},
 		},
 		aliceChannel,
-		startingHeight,
 	)
 	if err := aliceServer.htlcSwitch.AddLink(aliceChannelLink); err != nil {
 		t.Fatalf("unable to add alice channel link: %v", err)
@@ -943,13 +928,6 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 		}
 	}()
 
-	bobFirstEpochChan := make(chan *chainntnfs.BlockEpoch)
-	bobFirstEpoch := &chainntnfs.BlockEpochEvent{
-		Epochs: bobFirstEpochChan,
-		Cancel: func() {
-		},
-	}
-	firstBobTicker := time.NewTicker(50 * time.Millisecond)
 	firstBobChannelLink := NewChannelLink(
 		ChannelLinkConfig{
 			Switch:             bobServer.htlcSwitch,
@@ -964,7 +942,6 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 			},
 			FetchLastChannelUpdate: mockGetChanUpdateMessage,
 			Registry:               bobServer.registry,
-			BlockEpochs:            bobFirstEpoch,
 			FeeEstimator:           feeEstimator,
 			PreimageCache:          pCache,
 			UpdateContractSignals: func(*contractcourt.ContractSignals) error {
@@ -972,12 +949,14 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 			},
 			ChainEvents:         &contractcourt.ChainEventSubscription{},
 			SyncStates:          true,
-			BatchTicker:    &mockTicker{firstBobTicker.C},
-			FwdPkgGCTicker: &mockTicker{time.NewTicker(5 * time.Second).C},
 			BatchSize:           10,
+			BatchTicker:         &mockTicker{time.NewTicker(batchTimeout).C},
+			FwdPkgGCTicker:      &mockTicker{time.NewTicker(fwdPkgTimeout).C},
+			MinFeeUpdateTimeout: feeUpdateTimeout,
+			MaxFeeUpdateTimeout: feeUpdateTimeout,
+			OnChannelFailure:    func(lnwire.ChannelID, lnwire.ShortChannelID, LinkFailureError) {},
 		},
 		firstBobChannel,
-		startingHeight,
 	)
 	if err := bobServer.htlcSwitch.AddLink(firstBobChannelLink); err != nil {
 		t.Fatalf("unable to add first bob channel link: %v", err)
@@ -992,13 +971,6 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 		}
 	}()
 
-	bobSecondEpochChan := make(chan *chainntnfs.BlockEpoch)
-	bobSecondEpoch := &chainntnfs.BlockEpochEvent{
-		Epochs: bobSecondEpochChan,
-		Cancel: func() {
-		},
-	}
-	secondBobTicker := time.NewTicker(50 * time.Millisecond)
 	secondBobChannelLink := NewChannelLink(
 		ChannelLinkConfig{
 			Switch:             bobServer.htlcSwitch,
@@ -1013,7 +985,6 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 			},
 			FetchLastChannelUpdate: mockGetChanUpdateMessage,
 			Registry:               bobServer.registry,
-			BlockEpochs:            bobSecondEpoch,
 			FeeEstimator:           feeEstimator,
 			PreimageCache:          pCache,
 			UpdateContractSignals: func(*contractcourt.ContractSignals) error {
@@ -1021,12 +992,14 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 			},
 			ChainEvents:         &contractcourt.ChainEventSubscription{},
 			SyncStates:          true,
-			BatchTicker:    &mockTicker{secondBobTicker.C},
-			FwdPkgGCTicker: &mockTicker{time.NewTicker(5 * time.Second).C},
 			BatchSize:           10,
+			BatchTicker:         &mockTicker{time.NewTicker(batchTimeout).C},
+			FwdPkgGCTicker:      &mockTicker{time.NewTicker(fwdPkgTimeout).C},
+			MinFeeUpdateTimeout: feeUpdateTimeout,
+			MaxFeeUpdateTimeout: feeUpdateTimeout,
+			OnChannelFailure:    func(lnwire.ChannelID, lnwire.ShortChannelID, LinkFailureError) {},
 		},
 		secondBobChannel,
-		startingHeight,
 	)
 	if err := bobServer.htlcSwitch.AddLink(secondBobChannelLink); err != nil {
 		t.Fatalf("unable to add second bob channel link: %v", err)
@@ -1041,13 +1014,6 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 		}
 	}()
 
-	carolBlockEpoch := make(chan *chainntnfs.BlockEpoch)
-	carolEpoch := &chainntnfs.BlockEpochEvent{
-		Epochs: bobSecondEpochChan,
-		Cancel: func() {
-		},
-	}
-	carolTicker := time.NewTicker(50 * time.Millisecond)
 	carolChannelLink := NewChannelLink(
 		ChannelLinkConfig{
 			Switch:             carolServer.htlcSwitch,
@@ -1062,7 +1028,6 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 			},
 			FetchLastChannelUpdate: mockGetChanUpdateMessage,
 			Registry:               carolServer.registry,
-			BlockEpochs:            carolEpoch,
 			FeeEstimator:           feeEstimator,
 			PreimageCache:          pCache,
 			UpdateContractSignals: func(*contractcourt.ContractSignals) error {
@@ -1070,12 +1035,14 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 			},
 			ChainEvents:         &contractcourt.ChainEventSubscription{},
 			SyncStates:          true,
-			BatchTicker:    &mockTicker{carolTicker.C},
-			FwdPkgGCTicker: &mockTicker{time.NewTicker(5 * time.Second).C},
 			BatchSize:           10,
+			BatchTicker:         &mockTicker{time.NewTicker(batchTimeout).C},
+			FwdPkgGCTicker:      &mockTicker{time.NewTicker(fwdPkgTimeout).C},
+			MinFeeUpdateTimeout: feeUpdateTimeout,
+			MaxFeeUpdateTimeout: feeUpdateTimeout,
+			OnChannelFailure:    func(lnwire.ChannelID, lnwire.ShortChannelID, LinkFailureError) {},
 		},
 		carolChannel,
-		startingHeight,
 	)
 	if err := carolServer.htlcSwitch.AddLink(carolChannelLink); err != nil {
 		t.Fatalf("unable to add carol channel link: %v", err)
@@ -1093,22 +1060,13 @@ func newThreeHopNetwork(t testing.TB, aliceChannel, firstBobChannel,
 	return &threeHopNetwork{
 		aliceServer:      aliceServer,
 		aliceChannelLink: aliceChannelLink.(*channelLink),
-		aliceBlockEpoch:  aliceEpochChan,
-		aliceTicker:      aliceTicker,
-
-		firstBobChannelLink: firstBobChannelLink.(*channelLink),
-		bobFirstBlockEpoch:  bobFirstEpochChan,
-		firstBobTicker:      firstBobTicker,
 
 		bobServer:            bobServer,
+		firstBobChannelLink:  firstBobChannelLink.(*channelLink),
 		secondBobChannelLink: secondBobChannelLink.(*channelLink),
-		bobSecondBlockEpoch:  bobSecondEpochChan,
-		secondBobTicker:      secondBobTicker,
 
-		carolChannelLink: carolChannelLink.(*channelLink),
 		carolServer:      carolServer,
-		carolBlockEpoch:  carolBlockEpoch,
+		carolChannelLink: carolChannelLink.(*channelLink),
-		carolTicker:      carolTicker,
 
 		feeEstimator: feeEstimator,
 		globalPolicy: globalPolicy,

peer.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"container/list"
 	"fmt"
 	"net"
@@ -9,14 +10,11 @@ import (
 	"time"
 
 	"github.com/davecgh/go-spew/spew"
-	"github.com/lightningnetwork/lnd/brontide"
-	"github.com/lightningnetwork/lnd/contractcourt"
-
-	"bytes"
-
 	"github.com/go-errors/errors"
+	"github.com/lightningnetwork/lnd/brontide"
 	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/channeldb"
+	"github.com/lightningnetwork/lnd/contractcourt"
 	"github.com/lightningnetwork/lnd/htlcswitch"
 	"github.com/lightningnetwork/lnd/lnrpc"
 	"github.com/lightningnetwork/lnd/lnwallet"
@@ -537,7 +535,6 @@ func (p *peer) addLink(chanPoint *wire.OutPoint,
 		ForwardPackets: p.server.htlcSwitch.ForwardPackets,
 		FwrdingPolicy:  *forwardingPolicy,
 		FeeEstimator:   p.server.cc.feeEstimator,
-		BlockEpochs:    blockEpoch,
 		PreimageCache:  p.server.witnessBeacon,
 		ChainEvents:    chainEvents,
 		UpdateContractSignals: func(signals *contractcourt.ContractSignals) error {
@@ -553,9 +550,11 @@ func (p *peer) addLink(chanPoint *wire.OutPoint,
 			time.NewTicker(time.Minute)),
 		BatchSize:           10,
 		UnsafeReplay:        cfg.UnsafeReplay,
+		MinFeeUpdateTimeout: htlcswitch.DefaultMinLinkFeeUpdateTimeout,
+		MaxFeeUpdateTimeout: htlcswitch.DefaultMaxLinkFeeUpdateTimeout,
 	}
-	link := htlcswitch.NewChannelLink(linkCfg, lnChan,
+
-		uint32(currentHeight))
+	link := htlcswitch.NewChannelLink(linkCfg, lnChan)
 
 	// With the channel link created, we'll now notify the htlc switch so
 	// this channel can be used to dispatch local payments and also

server.go

@@ -284,6 +284,11 @@ func newServer(listenAddrs []string, chanDB *channeldb.DB, cc *chainControl,
 			debugPre[:], debugHash[:])
 	}
 
+	_, currentHeight, err := s.cc.chainIO.GetBestBlock()
+	if err != nil {
+		return nil, err
+	}
+
 	s.htlcSwitch, err = htlcswitch.New(htlcswitch.Config{
 		DB:      chanDB,
 		SelfKey: s.identityPriv.PubKey(),
@@ -313,7 +318,8 @@ func newServer(listenAddrs []string, chanDB *channeldb.DB, cc *chainControl,
 		SwitchPackager:         channeldb.NewSwitchPackager(),
 		ExtractErrorEncrypter:  s.sphinx.ExtractErrorEncrypter,
 		FetchLastChannelUpdate: fetchLastChanUpdate(s, serializedPubKey),
-	})
+		Notifier:               s.cc.chainNotifier,
+	}, uint32(currentHeight))
 	if err != nil {
 		return nil, err
 	}

test_utils.go

@@ -341,10 +341,17 @@ func createTestPeer(notifier chainntnfs.ChainNotifier,
 		breachArbiter: breachArbiter,
 		chainArb:      chainArb,
 	}
+
+	_, currentHeight, err := s.cc.chainIO.GetBestBlock()
+	if err != nil {
+		return nil, nil, nil, nil, err
+	}
+
 	htlcSwitch, err := htlcswitch.New(htlcswitch.Config{
 		DB:             dbAlice,
 		SwitchPackager: channeldb.NewSwitchPackager(),
-	})
+		Notifier:       notifier,
+	}, uint32(currentHeight))
 	if err != nil {
 		return nil, nil, nil, nil, err
 	}